Electronic transmission control and method therefor

• US 4,208,925 A
• Filed: 08/11/1977
• Issued: 06/24/1980
• Est. Priority Date: 08/11/1977
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Americas Company (Caterpillar Incorporated)
• Inventors: Miller, Robert G., Render, Michael L.
• Primary Examiner(s): Braun, Leslie
• Application Number:
  US05/823,769
• Time in Patent Office: 1,048 Days
• Field of Search: 74/866
• US Class Current: 477/63
• CPC Class Codes: B60R 16/0236 for economical driving
• CPC Class Codes: B60W 10/026 of lock-up clutches
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: F16H 59/36 Inputs being a function of speed
• CPC Class Codes: F16H 59/40 Output shaft speed
• CPC Class Codes: F16H 59/70 dependent on the ratio established
• CPC Class Codes: F16H 61/0213 characterised by the method for generating shift signals
• CPC Class Codes: F16H 61/14 Control of torque converter lock-up clutches
• CPC Class Codes: F16H 61/16 Inhibiting or initiating shift during unfavourable conditions, e.g. preventing forward reverse shift at high vehicle speed, preventing engine over speed unintentional control input F16H61/18
• CPC Class Codes: Y02T 10/84 Data processing systems or methods, management, administration
• CPC Class Codes: Y10T 74/19251 Control mechanism
• CPC Class Codes: Y10T 74/1926 Speed responsive

Abstract

A control for the automatic shifting of a multi-ratio power transmission. A memory is provided and programmed with the optimum vehicle speed shift points for upshift and downshift from each gear of the automatic range. The actual speed of the vehicle is periodically sampled, and each time it is, such speed is compared with the shift points for the gear which the transmission is in to see if a shift from such gear should be made. If it is determined from the speed sample that an upshift should be made, then the upshift speed points of higher gears are examined with reference to such speed sample to find the gear to which the transmission should be upshifted, i.e., the gear just above the highest gear having an upshift speed point which is less than the sampled speed. Having found such gear, the transmission is shifted thereto. Correspondingly, if it is determined from the speed sample that a downshift should be made (or can be made, in the event of a forced downshift condition), the downshift speed points of lower gears are examined with reference to such speed to find the gear to which a downshift should be made, i.e., the gear just below the lowest gear having a downshift speed point above the sampled speed. At any time, the operator may set any gear in the automatic range as the highest gear so that the transmission will not upshift beyond such gear.

Claims

1. The method of shifting a transmission having a plurality of gears progressively increasing in ratio from a minimum gear to a maximum gear, said method comprising:

(a) predetermining the upshift transmission speed point and the downshift transmission speed point for each of said gears,

(b) obtaining a sample of the instantaneous actual transmission speed,

(c) comparing said speed sample with at least one of the shift points of the actual gear in which said transmission is operating,

(d) determining if said speed sample is either above the upshift speed point or below the downshift speed point of said actual gear,

(e) if a determination is made in step (d) that said speed sample is above the upshift speed point of said actual gear, the further steps of;

(1) comparing said speed sample with the upshift speed points of gears progressively higher than said actual gear,

(2) finding the first of said progressively higher gears having an upshift speed point greater than said speed sample,

(3) shifting said transmission from said actual gear to the gear found in step (e)(2),

(f) if a determination is made in step (d) that said speed sample is less than the downshift speed point of said actual gear, the further steps of;

(1) comparing said speed sample with the downshift speed points of gears progressively lower than said actual gear,

(2) finding the first of said progressively lower gears having a downshift speed point lower than said speed sample,

(3) shifting said transmission from said actual gear to the gear found in step (f)(2).

2. The method of shifting a transmission having a plurality of gears progressively increasing in ratio from a minimum gear to a maximum gear, said method comprising:

(a) predetermining the upshift transmission speed point and the downshift transmission speed point for each of said gears,

(b) periodically obtaining samples of the instantaneous actual speed of said transmission,

(c) comparing the actual gear the transmission is in which said minimum and maximum gears,

(d) comparing one of said speed samples with at least one of the shift points of the actual gear in which said transmission is operating,

(e) determining if either of the following two conditions exists;

(1) the actual gear is lower than the maximum gear and said speed sample is above the upshift speed joint for the actual gear,

(2) the actual gear is above the minimum gear and said speed sample is below the downshift speed point for the actual gear,

and if so, carry out one of the steps (f) or (g),

(f) if a determination is made in step (e) that the condition (e)(1) exists, the further steps of;

(1) simultaneously comparing said speed sample with the upshift speed points of gears progressively higher than said actual gear, and comparing said progressively higher gears with said maximum gear,

(2) finding the first of said progressively higher gears which is either the same as the maximum gear or which has an upshift speed point greater than said speed sample,

(3) shifting said transmission from said actual gear to the gear found in step (f)(2),

(g) if a determination is made in step (e) that the condition (e)(2) exists, the further steps of;

(1) simultaneously comparing said speed sample with the downshift speed points of gears progressively lower than said actual gear, and comparing said progressively lower gears with said minimum gear,

(2) finding the first of said progressively lower gears which is either the same as said minimum gear or which has a downshift speed point lower than said speed sample,

(3) shifting said transmission from said actual gear to the gear found in step (g)(2).

3. The method as set forth in claim 2,

wherein step (f) further includes, subsequent to step (f)(2), repeating steps (c), (d), (e), (f)(1) and (f)(2) with subsequent speed sample signals and carrying out step (f)(3) with respect to the gear found in one of the (f)(2) steps, when, and only when, the condition (e)(1) exists with respect to each of a predetermined number of consecutive speed samples, and

wherein step (g) further includes, subsequent to step (g)(2), repeating steps (c), (d), (e), (f)(1) and (f)(2) with subsequent speed samples and carrying out step (f)(3) with respect to the desired gear found in one of the (f)(2) steps, when, and only when, the condition (e)(2) exists with respect to each of a predetermined number of consecutive speed samples.

4. The method of upshifting a transmission having an automatic range comprising a plurality of gears progressively increasing in ratio from a minimum gear to a maximum gear, said method comprising:

(a) predetermining the upshift transmission speed points for each of the gears in said range and generating separate signals for said speed points,

(b) generating separate signals indicative of the actual gear that said transmission is in and gears progressively higher than said actual gear,

(c) generating a signal indicative of said maximum gear,

(d) generating a speed signal indicative of the actual speed of said transmission,

(e) comparing said maximum gear signal separately with said signals for said actual gear and said progressively higher gears,

(f) comparing said transmission speed signal separately with the upshift speed point for said actual gear and said progressively higher gears,

(g) determining from said comparison of steps (e) and (f), the highest gear wherein both of the following conditions exist;

(1) such highest gear is below said maximum gear,

(2) the upshift speed point for such highest gear is below the actual transmission,

(h) determining the gear next higher than the gear determined in step (g),

(i) shifting said transmission from said actual gear to said gear determined in step (h).

5. The method of upshifting a transmission having an automatic range comprising a plurality of gears progressively increasing in ratio from a mimimum gear to a maximum gear, said method comprising:

(a) generating a gear signal indicative of the actual gear that said transmission is in,

(b) generating a gear signal indicative of said maximum gear,

(c) generating a speed signal indicative of the actual transmission speed,

(d) generating an upshift speed point signal indicative of the transmission speed at which an upshift can be made from said actual gear,

(e) comparing said gear signals of steps (a) and (b) and determining if the condition exists that said actual gear is below said maximum gear,

(f) comparing said transmission speed and said speed point signals of steps (c) and (d) and determining if the condition exists that the actual transmission speed is above the upshift speed point for said actual gear,

(g) carrying out the following steps if the conditions of steps (e) and (f) both exist,

(h) generating a gear signal indicative of the next-higher gear than said actual gear,

(i) generating an upshift speed point signal indicative of the transmission speed at which an upshift can be made from said next-higher gear,

(j) comparing said gear signals of steps (b) and (h) and determining if the condition exists that said next-higher gear is below said maximum gear,

(k) comparing said transmission speed and speed point signals of steps (c) and (i) and determining if the condition exists that the actual transmission speed is above the upshift speed point for said next-higher gear,

(l) repeating steps (h) through (k), if necessary, with a progressively higher gear each time, and determining which gear higher than said actual gear is the first gear wherein at least one of the conditions of steps (j) and (k) is not met,

(m) shifting said transmission from said actual gear directly to said first gear determined in step (l).

6. The method of downshifting a transmission having an automatic range comprising a plurality of gears progressively increasing in ratio from a minimum gear to a maximum gear, said method comprising:

(a) predetermining the downshift transmission speed points for each of the gears in said range and generating separate signals for said speed points,

(b) generating separate signals indicative of the actual gear that said transmission is in and gears progressively lower than said actual gear,

(c) generating a signal indicative of said minimum gear,

(d) generating a speed signal indicative of the actual speed of said transmission,

(e) comparing said minimum gear signal separately with said signals for said actual gear and said progressively lower gears,

(f) comparing said transmission speed signal separately with the downshift speed point signals for said actual gear and said progressively lower gears,

(g) determining from said comparison of steps (e) and (f), the lowest gear wherein both of the following conditions exist;

(1) such lowest gear is above said minimum gear,

(2) the downshift speed point for such lowest gear is above the actual transmission speed,

(h) determining the gear next lower than the gear determined in step (g),

(i) shifting said transmission from said actual gear to said gear determined in step (h).

7. The method of downshifting a transmission having an automatic range comprising a plurality of gears progressively increasing in ratio from a minimum gear to a maximum gear, said method comprising:

(a) generating a gear signal indicative of the actual gear that said transmission is in,

(b) generating a gear signal indicative of said minimum gear,

(c) generating a speed signal indicative of the actual transmission speed,

(d) generating a downshift speed point signal indicative of the transmission speed at which a downshift can be made from said actual gear,

(e) comparing said gear signals of steps (a) and (b) and determining if the condition exists that said actual gear is above said minimum gear,

(f) comparing said transmission speed and said speed point signals of steps (c) and (d) and determining if the condition exists that the actual transmission speed is below the downshift speed point for said actual gear,

(g) carrying out the following steps if the condition of steps (e) and (f) both exist,

(h) generating a gear signal indicative of the next-lower gear than said actual gear,

(i) generating a downshift speed point signal indicative of the transmission speed at which a downshift can be made from said next-lower gear,

(j) comparing said gear signals of steps (b) and (h) and determining if the condition exists that said next-lower gear is above said minimum gear,

(k) comparing said transmission speed and speed point signals of steps (c) and (i) and determining if the condition exists that the actual transmission speed is below the downshift speed point for said next-lower gear,

(l) repeating steps (h) through (k), if necessary, with a progressively lower gear each time, and determining which gear lower than said actual gear is the first gear wherein at least one of the conditions of steps (j) and (k) is not met,

(m) shifting said transmission from said actual gear directly to said first gear determined in step (l).

8. The method of shifting a transmission having an automatic range comprising a plurality of gears progressively increasing from a minimum gear to a maximum gear, said transmission having a gear-selector cane for selecting a maximum operating gear, said method comprising:

(a) initially selecting a maximum operating gear in said range and operating said transmission in said automatic range in a gear above said minimum gear and no higher than said initially selected maximum operating gear,

(b) subsequently selecting a maximum operating gear in said range which is lower than the actual gear said transmission is operating in,

(c) predetermining the downshift speed points for each gear of said automatic range to the next lower gear of said range, and generating separate signals indicative of each of said speed points,

(d) generating signals each representative of said subsequently selected maximum operating gear, and said actual gear,

(e) periodically sampling the instantaneous actual speed of said transmission and generating speed sample signals indicative of the speed of each sample,

(f) comparing said actual gear signal with said subsequently selected maximum operating gear signals,

(g) comparing one of said speed sample signals with the downshift speed point signal for said actual gear,

(h) determining from the comparison of steps (f) and (g) whether the following conditions exist;

(1) the gear signals are indicative that said actual gear is higher than said subsequently selected maximum operating gear, and

(2) the speed signals are indicative that the actual transmission speed is lower than the downshift speed point for the actual gear,

(i) if in step (h) it is determined that the two conditions are not met, repeat steps (e), (f), (g) and (h) with subsequent speed sample signals until both conditions of step (h) are met,

(j) generating, after both conditions of the first or subsequent step (h) have been met, gear signals indicative of gears progressively lower than said actual gear,

(k) comparing said gear signals of said progressively lower gears with said subsequently selected maximum operating gear signal,

(l) comparing the speed sample signal used in the step (h) wherein all three conditions of step (h) were first met with the downshift speed point signals for said progressively lower gears,

(m) determining from the comparison of steps (k) and (l) which is the first of said progressively lower gears wherein either one of the following two conditions exists;

(1) the gear signals are indicative that said lower gear is the same as said subsequently selected maximum operating gear,

(2) the speed signals are indicative that the actual transmission speed is above the downshift speed point of said lower gear,

(n) shifting said transmission from said actual gear to said first of said progressively lower gears wherein one of the conditions of step (m) exists,

(o) repeating steps (d)-(n) as often as necessary until said transmission is shifted to the gear selected in step (b).

9. The method of shifting a transmission having an automatic range comprising a plurality of gears progressively increasing from a minimum gear to a maximum gear, said transmission having a gear-selector cane for selecting a maximum operating gear, said method comprising:

(a) initially selecting a maximum operating gear in said range and operating said transmission in said automatic range in a gear above said minimum gear and no higher than said initially selected maximum operating gear,

(b) subsequently selecting a maximum operating gear lower than the actual gear said transmission is operating in,

(c) predetermining the downshift speed points for each gear of said automatic range to the next lower gear of said range, and generating separate signals indicative of each of said speed points,

(d) generating signals representative of said minimum gear, said subsequently selected maximum operating gear, and said actual gear,

(e) periodically sampling the instantaneous actual speed of said transmission and generating speed sample signals indicative of the speed of each sample,

(f) comparing said actual gear signal with said subsequently selected maximum and minimum gear signals,

(g) comparing one of said speed sample signals with the downshift speed point signal for said actual gear,

(h) determining from the comparison of steps (f) and (g) whether the following conditions exist;

(1) the gear signals are indicative that said actual gear is higher than said subsequently selected maximum operating gear, and

(2) the gear signals are indicative that said actual gear is higher than said minimum gear, and

(3) the speed signals are indicative that the actual transmission speed is lower than the downshift speed point for the actual gear,

(i) if in step (h) it is determined that not all three of the conditions are met, repeat steps (e), (f), (g) and (h) with subsequent speed sample signals until all three conditions of step (h) are met,

(j) generating, after all three conditions of the first or subsequent step (h) have been met, gear signals indicative of gears progressively lower than said actual gear,

(k) comparing said gear signals of said progressively lower gears with said subsequently selected maximum and minimum gear signals,

(l) comparing the speed sample signal used in the step (h) wherein all three conditions of step (h) were first met with the downshift speed point signals for said progressively lower gears,

(m) determining from the comparison of steps (k) and (l) which is the first of said progressively lower gears wherein any one of the following conditions exists;

(1) the gear signals are indicative that said lower gear is the same as said subsequently selected maximum operating gear,

(2) the gear signals are indicative that said lower gear is the same as said minimum gear,

(3) the speed signals are indicative that the actual transmission speed is above the downshift speed point of said lower gear,

(n) shifting said transmission from said actual gear to said first of said progressively lower gears wherein one of the conditions of step (m) exists,

(o) repeating steps (d)-(n) as often as necessary until said transmission is shifted to the gear selected in step (b).

10. In a method of controlling the shifting of a transmission having a plurality of gears in an automatic range progressively increasing in ratio from a minimum gear to a maximum gear, said transmission having a gear-selector cane associated therewith for selecting the maximum operating gear in said range, the steps of:

(a) periodically sampling the instantaneous actual speed of said transmission and determining the transmission speed each time such speed is sampled,

(b) each time the transmission speed is sampled, and with respect to the minimum gear, the selected maximum operating gear and the actual gear the transmission is in at such time;

(1) determining whether the actual gear is higher than said maximum operating gear selected by said cane, and,

(a) if so, determining whether the transmission speed is below the predetermined downshift speed point for the actual gear, and,

(1) if so, determining the lowest gear to which said transmission may be shifted,

(2) if not, repeat steps (d)-(g) at the next time said transmission speed is sampled,

(b) if not,

(2) determining whether the actual gear is below said selected maximum operating gear and the transmission speed is above the predetermined upshift speed point for the actual gear, and,

(a) if so, determining the highest gear to which said transmission may be shifted,

(b) if not,

(3) determining whether the actual gear is above said minimum gear and the transmission speed is below the predetermined downshift speed point for the actual gear, and,

(a) if so, determining the lowest gear to which said transmission may be shifted,

(b) if not, repeat step (b) at the next time said transmission speed is sampled.

11. The method as set forth in claim 10 wherein step (b)(1)(a)(1) comprises:

(a) determining with respect to said selected maximum operating gear and the gear next lower than said actual gear, and with respect to the same transmission speed sample, whether said next lower gear is higher than said maximum operating gear and whether the transmission speed is below the predetermined downshift speed point for said next lower gear, and

(1) if both conditions are determined to exist with respect to the lower gear being considered, repeating such step with respect to progressively lower gears until a determination is made that at least one of such conditions is not met with respect to the gear being considered,

(2) determining that the gear being considered is the lowest gear to which said transmission may be shifted when a determination is made that at least one of such conditions is not met with respect to such gear being considered.

12. The method as set forth in claim 10 and further including:

(c) determining when step (b)(1)(a)(1) has been performed with respect to a predetermined number of consecutive transmission speed samples,

(d) shifting said transmission from said actual gear to the lowest gear determined in a selected one of said (b)(1)(a)(1) steps when the determination in step (h) has been made.

13. The method as set forth in claim 10 and further including:

(c) determining when step (b)(2)(a) has been performed with respect to at least three consecutive transmission speed samples,

(d) shifting said transmission from said actual gear to the highest gear determined in a selected one of said (b)(2)(a) steps when the determination in step (h) has been made.

14. The method as set forth in claim 10 wherein step (b)(2)(a) comprises:

(1) determining with respect to said selected maximum operating gear and the gear next higher than said actual gear, and with respect to the same transmission speed sample, whether said next higher gear is lower than said maximum operating gear and whether the transmission speed is above the predetermined upshift speed point for said next higher gear, and

(a) if both conditions are determined to exist with respect to the higher gear being considered, repeating such step with respect to progressively higher gears until a determination is made that at least one of such conditions is not met with respect to the gear being considered,

(b) determining that the gear being considered is the highest gear to which said transmission may be shifted when a determination is made that at least one of such conditions is not met with respect to such gear being considered.

15. The method as set forth in claim 10 and further including:

(c) determining when step (b)(2)(a) has been performed with respect to a predetermined number of consecutive transmission speed samples,

(d) shifting said transmission from said actual gear to the highest gear determined in a selected one of said (b)(2)(a) steps when the determination in step (h) has been made.

16. The method as set forth in claim 10 and further including:

(c) determining when step (b)(1)(a)(1) has been performed with respect to at least three consecutive transmission speed samples,

(d) shifting said transmission from said actual gear to the lowest gear determined in a selected one of said (b)(1)(a)(1) steps when the determination in step (h) has been made.

17. The method as set forth in claim 16, and further including:

(e) operating said transmission in direct mechanical drive when said transmission is in a gear higher than said minimum gear,

(f) operating said transmission in torque converter drive while carrying out the shifting step (d) and for a predetermining period of time following completion of said shifting step and thereafter returning said transmission to operating in direct mechanical drive.

18. The method as set forth in claim 10 wherein step (b)(3)(a) comprises:

(1) determining with respect to said minimum gear and the gear next lower than said actual gear, and with respect to the same transmission speed sample, whether said next lower gear is higher than said minimum gear and whether the transmission speed is below the predetermined downshift speed point for said next lower gear, and

(b) if both conditions are determined to exist with respect to the lower gear being considered, repeating such step with respect to progressively lower gears until a determination is made that at least one of such conditions is not met with respect to the gear being considered,

(c) determining that the gear being considered is the lowest gear to which said transmission may be shifted when a determination is made that at least one of such conditions is not met with respect to such gear being considered.

19. The method as set forth in claim 10 and further including:

(c) determining when step (b)(3)(a) has been performed with respect to a predetermined number of consecutive transmission speed samples,

(d) shifting said transmission from said actual gear to the lowest gear determined in a selected one of said (b)(3)(a) steps when the determination in step (h) has been made.

20. The method as set forth in claim 10 and further including:

(c) determining when step (b)(3)(a) has been performed with respect to at least three consecutive transmission speed samples,

(d) shifting said transmission from said actual gear to the lowest gear determined in a selected one of said (b)(3)(a) steps when the determination in step (h) has been made.

21. The method as set forth in claim 20, and further including:

(e) operating said transmission in direct mechanical drive when said transmission is in a gear higher than said minimum gear,

(f) operating said transmission in torque converter drive while carrying out the shifting step (d) and for a predetermining period of time following completion of said shifting step and thereafter returning said transmission to operation in direct mechanical drive.

22. In a method of controlling the shifting of a transmission having a plurality of gears in an automatic range progressively increasing in ratio from a minimum gear to a maximum gear, said transmission having a gear-selector cane associated therewith for selecting the maximum operating gear in said range, the steps of:

(a) predetermining the upshift and downshift transmission speed points for each of said gears and providing for the generation of separate signals indicative of each of said speed points,

(b) generating separate signals indicative of said minimum gear, said maximum operating gear and the actual gear which said transmission is in,

(c) periodically sampling the instantaneous actual speed of said transmission and generating a speed signal indicative of the transmission speed each time such speed is sampled,

(d) comparing said actual gear signal and said minimum gear signal each time the transmission speed is sampled,

(e) comparing said actual gear signal and said maximum operating gear signal each time the transmission speed is sampled,

(f) comparing said transmission speed signal with at least one of the speed point signals for said actual gear each time the transmission speed is sampled,

(g) each time the transmission speed is sampled, and from said comparisons of said gear signals and speed signals existing at such time;

(1) determining whether the actual gear is higher than said maximum operating gear selected by said cane, and,

(a) if so, determining whether the transmission speed is below the downshift speed point for the actual gear, and,

(1) if so, determining the lowest gear to which said transmission may be shifted,

(2) if not, repeat steps (d)-(g) at the next time said transmission speed is sampled,

(b) if not,

(2) determining whether the actual gear is below said selected maximum operating gear and the transmission speed is above the upshift speed point for the actual gear, and,

(a) if so, determining the highest gear to which said transmission may be shifted,

(b) if not,

(3) determining whether the actual gear is above said minimum gear and the transmission speed is below the downshift speed point for the actual gear, and,

(a) if so, determining the lowest gear to which said transmission may be shifted,

(b) if not, repeat steps (d)-(g) at the next time said transmission speed is sampled.

23. The method as set forth in claim 22 wherein step (g)(1)(a)(1) comprises:

(a) generating a gear signal indicative of the gear next lower than said actual gear,

(b) comparing said next-lower gear signal and said maximum operating gear,

(c) comparing the same transmission speed signal used in step (g)(1) with the downshift speed point signal for said next-lower gear,

(d) determining from said comparison whether said next-lower gear is greater than said maximum operating gear and whether the transmission speed is below the downshift speed point for said next-lower gear, and

(1) if both conditions are determined to exist with respect to said lower gear, repeating steps (g)(1)(a)(1)(a)-(d) with progressively lower gears until a determination is made that one of such conditions does not exist with respect to the gear being considered,

(2) determining that the lower gear being considered is the lowest gear to which the transmission may be shifted when a determination is made with respect to such gear that one of such conditions does not exist.

24. The method as set forth in claim 22 and further including:

(h) determining when step (a)(1)(a)(1) has been performed with respect to a predetermined number of consecutive transmission speed samples,

(i) shifting said transmission from said actual gear to the lowest gear determined in a selected one of said (g)(1)(a)(1) steps when the determination in step (h) has been made.

25. The method as set forth in claim 22 wherein step (g)(2)(a) comprises:

(1) generating a gear signal indicative of the gear next-higher than said actual gear,

(2) comparing said next-higher gear signal and said maximum operating gear,

(3) comparing the same transmission speed signal used in step (g)(2) with the upshift speed point signal for said next-higher gear,

(4) determining from said comparison whether said next-higher gear is lower than said maximum operating gear and whether the transmission speed is above the downshift speed point for said next-lower gear, and

(a) if both conditions are determined to exist with respect to said lower gear, repeating steps (g)(2)(a)(1)-(4) with progressively higher gears until a determination is made that one of such conditions does not exist with respect to the gear being considered,

(b) determining that the higher gear being considered is the highest gear to which the transmission may be shifted when a determination is made with respect to such gear that one of such conditions does not exist.

26. The method as set forth in claim 22 and further including:

(h) determining when step (g)(2)(a) has been performed with respect to a predetermined number of consecutive transmission speed samples,

(i) shifting said transmission from said actual gear to the highest gear determined in a selected one of said (g)(2)(a) steps when the determination in step (h) has been made.

27. The method as set forth in claim 26 and further including:

(j) periodically sampling the instantaneous actual engine speed,

(k) generating an overspeed signal in the event any sample of such actual engine speed exceeds a predetermined value,

(l) immediately upshifting the transmission one gear in response to the generation of said overspeed signal.

28. The method as set forth in claim 27 and further including:

(m) inhibiting upshifting of said transmission in response to said overspeed signal when said transmission is operating in said maximum operating gear.

29. The method as set forth in claim 22 wherein step (g)(3)(a) comprises:

(a) generating a gear signal indicative of the gear next-lower than said actual gear,

(b) comparing said next-lower gear signal and said minimum gear,

(c) comparing the same transmission speed signal used in step (g)(3) with the downshift speed point signal for said next-lower gear,

(d) determining from said comparison whether said next-lower gear is above said minimum gear and whether the transmission speed is below the downshift speed point for said next-lower gear, and

(1) if both conditions are determined to exist with respect to said lower gear, repeating steps (g)(3)(a)(1)-(4) with progressively lower gears until a determination is made that one of such conditions does not exist with respect to the gear being considered,

(2) determining that the lower gear being considered is the lowest gear to which the transmission may be shifted when a determination is made with respect to such gear that one of such conditions does not exist.

30. The method as set forth in claim 22 and further including:

(h) determining when step (g)(3)(a) has been performed with respect to a predetermined number of consecutive transmission speed samples,

(i) shifting said transmission from said actual gear to the lowest gear determined in a selected one of said (g)(3)(a) steps when the determination in step (h) has been made.

31. The method as set forth in claim 22 and wherein a determination has been made in step (g) of a gear to which the transmission should be shifted, the further steps of:

(h) comparing said actual gear signal with the signal fo the determined gear found in step (g),

(i) generating a shift signal for as long as the actual and determined gear signals are dissimilar,

(j) shifting said transmission in response to said shift signal from the existing actual gear towards said determined gear,

(k) generating new actual gear signals indicative of new positions of said transmission as said transmission is shifted,

(l) comparing said new actual gear signals with said determined gear signal,

(m) discontinuing said shifting when the gear signal comparison of the preceding step is indicative that the new transmission position is the same as said determined gear.

32. The method as set forth in claim 22 and further including:

operating said transmission in direct mechanical drive only when said transmission is in a gear higher than said minimum gear,

predetermining a transmission speed reference point for changing from torque converter drive to direct mechanical drive when operating in said minimum gear and providing for the generation of a speed reference signal for such transmission speed point,

comparing said actual transmission speed sample signals with said speed reference signal when said transmission is operating in said minimum gear,

operating said transmission in torque converter drive when the comparison of the preceding step is indicative that the actual transmission speed is less than said speed reference and operating said transmission in direct mechanical drive when said comparison is indicative that said actual transmission speed is greater than said speed reference.

33. The method of shifting a transmission having a plurality of gears in an automatic range progressively increasing in ratio from a minimum gear to a maximum gear, said transmission having a gear-selector cane associated therewith for selecting a maximum operting gear in said range, said method comprising:

(a) predetermining the upshift and downshift transmission speed points for each of said gears and providing for the generation of separate signals indicative of each of said speed points,

(b) generating separate signals indicative of said minimum gear and said maximum operating gear,

(c) generating a signal indicative of the actual gear that said transmission is in,

(d) periodically sampling the instantaneous actual speed of said transmission and generating a speed sample signal indicative of each speed sample,

(e) comparing said actual gear signal with said minimum and maximum operating gear signals,

(f) comparing one of said speed sample signals with at least one of the shift speed point signals for said actual gear,

(g) determining from the comparisons of steps (e) and (f) if either of the following two conditions exist;

(1) the gear signals are indicative that the actual gear is lower than the maximum operating gear and the speed signals are indicative that the transmission speed is above the upshift speed point for the actual gear,

(2) the gear signals are indicative that the actual gear is higher than the minimum gear and the speed signals are indicative that the transmission speed is below the downshift speed point for the actual gear, and, if so, carry out one of the steps (h) or (i),

(h) if a determination is made in step (g) that the condition (g)(1 ) exists, the further steps of;

(1) generating gear signals indicative of gears progressively higher than said actual gear and comparing said gear signals with the maximum gear signal, and comparing the same said speed sample signal with the upshift speed point signals for such progressively higher gears,

(2) finding the first of said progressively higher gears wherein either a gear signal comparison is indicative that said higher gear is the same as said maximum operating gear, or a speed signal comparison is indicative that the upshift speed point of said higher gear is higher than said transmission speed, said higher gear found being the desired gear to which said transmission should be shifted,

(3) shifting said transmission from said actual gear to said desired gear found in step (h)(2),

(i) if a determination is made in step (g) that the condition (g)(2) exists, the further steps of;

(1) generating gear signals indicative of gears progressively lower than said actual gear and comparing said signals with the minimum gear signal, and comparing the same speed sample signal with the downshift speed point signals for said progressively lower gears,

(2) finding the first of said progressively lower gears wherein either a gear signal comparison is indicative that said lower gear is the same as said minimum gear, or a speed signal comparison is indicative that the downshift speed point of said lower gear is lower than said transmission speed, said lower gear found being the desired gear to which said transmission should be shifted,

(3) shifting said transmission from said actual gear to said desired gear found in step (i)(2).

34. The method as set forth in claim 33,

wherein step (h) further includes, subsequent to step (h)(2), repeating steps (e), (f), (g), (h)(1) and (h)(2) with each of a number of subsequent speed sample signals, and carrying out step (h)(3) with respect to the desired gear found in a selected one of the (h)(2) steps, when, and only when, the condition (g)(1) exists with respect to each of a predetermined number of consecutive speed samples, and

wherein step (i) further includes, subsequent to step (i)(2), repeating steps (e), (f), (g), (i)(1) and (i)(2) with each of a number of subsequent speed samples and carrying out step (i)(3) with respect to the desired gear found in a selected one of the (i)(2) steps, when, and only when, the condition (g)(2) exists with respect to each of a predetermined number of consecutive speed samples.

35. The method as set forth in claim 34 and further including:

periodically sampling the instantaneous actual engine speed,

generating an overspeed signal in the event any sample of such actual engine speed exceeds a predetermined value,

overriding the carrying out of step (h) and immediately upshifting the transmission one gear in response to the generation of said overspeed signal.

36. The method as set forth in claim 35 and further including:

inhibiting upshifting of said transmission in response to said overspeed signal when said transmission is operating in said maximum gear.

37. The method as set forth in claim 34,

wherein step (h) includes inhibiting the carrying out of step (h)(3) if the desired gear found in the (h)(2) steps with respect to each of said predetermined number of consecutive speed samples is progressively decreasing, and

wherein step (i) includes inhibiting the carrying out of step (i)(3) if the desired gear found in the (i)(2) steps with respect to each of said predetermined number of consecutive speed samples is progressively increasing.

38. The method as set forth in claim 34,

wherein in step (h) the predetermined number of consecutive speed samples is three and wherein step (h) further includes selecting the desired gear for use in step (h)(3) from those found in the (h)(2) steps as follows:

selecting as the desired gear that found in the (h)(2) step carried out with respect to the second of the three consecutive speed samples, unless such desired gear is higher than that found in the (h)(2) steps carried out with respect to both the first and third of said three consecutive speed samples, in which event selecting the desired gear found in the (h)(2) step carried out with respect to said third speed sample, and

wherein in step (i) the predetermined number of consecutive speed samples is three and wherein step (i) further includes selecting the desired gear for use in step (i)(3) from those found in the (i)(2) steps as follows;

selecting as the desired gear that found in the (i)(2) step carried out with respect to the second of the three consecutive speed samples, unless such desired gear is lower than that found in the (i)(2) steps carried out with respect to both the first and third of said three consecutive speed samples, in which event selecting the desired gear found in the (h)(2) step carried out with respect to said third speed sample.

39. The method as set forth in claim 38,

wherein step (h) further includes inhibiting the carrying out of step (h)(3) if the desired gear found in each of the (h)(2) steps carried out with respect to said three consecutive speed samples is progressively decreasing, and

wherein step (i) further includes inhibiting the carrying out of step (i)(3) if the desired gear found in each of the (i)(2) steps carried out with respect to said three consecutive speed samples is progressively increasing.

40. The method as set forth in claim 33,

wherein step (g) further includes initially determining from the comparison of step (e) whether:

(g)(3) the gear signals are indicative that the actual gear is higher than the maximum operating gear, and

(i) if not, proceeding with the determination of the conditions (g)(1) and (g)(2) of step (g),

(ii) if so, omitting the determination of the conditions (g)(1) and (g)(2) of step (g) and, instead, determining from the comparison of step (f) whether;

(g)(4) the speed signals are indicative that the transmission speed is lower than the downshift speed point for the actual gear, and

(i) if not, repeat steps (e), (f) and (g) with subsequent speed sample signals until such time as step (g)(4) is indicative that the transmission speed is lower than the downshift speed point for the actual gear,

(ii) if so, carry out the following step (j),

(j)(1) generating gear signals indicative of gears progressively lower than said actual gear and comparing said signals with the maximum operating gear signal and comparing the last-used speed sample signal with the downshift speed point signals for such progressively lower gears,

(j)(2) finding the first of said progressively lower gears wherein either a gear signal comparison is indicative that said lower gear is the same as said maximum operating gear, or a speed signal comparison is indicative that the downshift speed point of said lower gear is lower than said transmission speed, said lower gear being the desired gear to which said transmission should be shifted,

(j)(3) shifting said transmission from said actual gear to said desired gear found in step (j)(2).

41. The method as set forth in claim 40,

wherein step (j) further includes, subsequent to step (j)(2) and prior to step (j)(3), repeating steps (e), (f), (g), (j)(1) and (j)(2) with subsequent speed sample signals and carrying out step (j)(3) with respect to the desired gear found in a selected one of the (j)(2) steps, when, and only when, the conditions (g)(3) and (g)(4) exist with respect to each of a predetermined number of consecutive speed samples.

42. The method as set forth in claim 33, and wherein a desired gear has been found in one of steps (h) or (i) and wherein the shifting portion of such step comprises:

comparing said actual gear signal with the signal for said desired gear found,

generating a shift signal for as long as the actual and desired gear signals are dissimilar,

shifting said transmission in response to said shift signal from the existing actual gear towards said desired gear,

generating new actual gear signals indicative of new positions of said transmission as said transmission is shifted,

comparing said new actual gear signals with said desired gear signal,

discontinuing said shifting when the gear signal comparison of the preceding step is indicative that the new transmission position is the same as said desired gear.

43. The method as set forth in claim 33 and further including:

repeating the steps of claim 33, after the transmission has been shifted, with subsequent speed sample signals and with the gear to which said transmission has been shifted being the actual gear for the repeated steps.

44. The method as set forth in claim 43 and further including the step of delaying for a predetermined period of time following a shift of said transmission before said steps of claim 33 are repeated.

45. The method as set forth in claim 33 and further including:

generating a hold signal,

inhibiting the step of shifting from said actual gear to a desired gear found in carrying out the steps of claim 33 for as long as said hold signal is present,

repeating the steps of claim 33, save for a shifting step, with respect to each of subsequent speed sample signals generated during the time that said hole signal is present,

removing the shifting inhibition when said hold signal ceases.

46. The method as set forth in claim 45, and further including:

periodically sampling the instantaneous engine speed,

generating an underspeed signal in the event a sample of said engine speed is indicative that said engine speed is below a predetermined value,

preventing said hold signal from further inhibiting shifting in the event said underspeed signal is generated.

47. The method as set forth in claim 33, and further including:

operating said transmission in direct mechanical drive when said transmission is in a gear higher than said minimum gear,

operating said transmission in torque converter drive while carrying out the shifting step (h)(3) or (i)(3) and for a predetermining period of time following completion of said shifting step and thereafter returning said transmission to operation in direct mechanical drive.

48. The method as set forth in claim 33 and further including:

operating said transmission in direct mechanical drive only when said transmission is in a gear higher than said minimum gear,

predetermining a transmission speed reference point for changing from torque converter drive to direct mechanical drive when operating in said minimum gear and providing for the generation of a speed reference signal for such transmission speed point,

comparing said actual transmission speed sample signals with said speed reference signal when said transmission is operating in said minimum gear,

operating said transmission in torque converter drive when the comparison of the preceding step is indicative that the actual transmission speed is less than said speed reference and operating said transmission in direct mechanical drive when said comparison is indicative that said actual transmission speed is greater than said speed reference.

49. The method as set forth in claim 48, and further including:

operating said transmission in torque converter drive while carrying out a step of shifting from an actual gear to a desired gear and for a predetermining period of time following completion of such shifting step and thereafter returning said transmission to operation in direct mechanical drive.

50. The method as set forth in claim 33 and further including:

periodically sampling the instantaneous actual engine speed,

generating an overspeed signal in the event any sample of such actual engine speed exceeds a predetermined value,

immediately upshifting the transmission one gear in response to the generation of said overspeed signal.

51. The method as set forth in claim 50 and further including:

inhibiting upshifting of said transmission in response to said overspeed signal when said transmission is operating in said maximum gear.

52. A control for a system including an engine and a transmission coupled to the output of said engine, said transmission having a plurality of gears in an automatic range which progressively increase in ratio from a preselected minimum automatic gear, said transmission having associated therewith an operator-controllable gear-selecting cane for selecting any of the gears of said transmission in said range, said control comprising:

means for generating a plurality of speed point signals, each indicative of the predetermined upshift or downshift transmission speed point for each of said gears of said automatic range,

means for generating separate signals indicative of said minimum gear, said maximum operating gear and the actual gear which said transmission is in,

means for periodically sampling the instantaneous speed of said transmission and for generating an actual speed signal indicative of the transmission speed each time such speed is sampled,

first comparator means for comparing said actual gear signal and said minimum gear signal each time the transmission speed is sampled,

second comparator means for comparing said actual gear signal and said maximum operating gear signal each time the transmission speed is sampled,

third comparator means for comparing said speed signal with at least one of the speed point signals for said actual gear each time the transmission is sampled,

gear-calculating means operable each time the transmission speed is sampled, and responsive to said first, second and third comparator means, said gear-calculating means including;

a first portion for determining whether the actual speed is above the upshift speed point for said actual gear when said actual gear is below said selected maximum operating gear, and, if so, for calculating the highest gear to which the transmission may be shifted, such highest gear being one immediately above a gear which is both lower than said maximum operating gear and has an upshift speed point lower than said actual speed, said highest gear being either said maximum operating gear or having an upshift speed point greater than said actual speed,

a second portion for determining whether the actual speed is below the downshift speed point for said actual gear when said actual gear is above said minimum gear, and, if so, for calculating the lowest gear to which the transmission may be shifted, such lowest gear being one immediately below a gear which is above said minimum gear and has a downshift speed point higher than said actual speed, said lowest gear being either said minimum gear or having a downshift speed point lower than said actual speed.

53. A control as set forth in claim 52, and wherein all of said means for generating signals indicative of gears and signals indicative of actual speed and speed points each include means for generating such signals in binary coded form.

54. A control as set forth in claim 52, wherein said means for generating speed point signals includes:

means for generating signals for each of said gears of said automatic range,

an addressable and programmable memory matrix, said matrix being programmed with predetermined upshift and downshift speed points for each of said gears and operable to produce signals corresponding to said speed points for a particular gear when a gear-indicative signal corresponding to such gear is addressed to said matrix.

55. Apparatus as set forth in claim 52, and further including:

means responsive to a calculation by said gear calculating means for shifting said transmission to the gear calculated thereby.

56. A control as set forth in claim 55 and further including:

means for generating a malfunction signal in response to a loss of actual speed signals,

means responsive to the generation of said malfunction signal for inhibiting shifting of said transmission from said actual gear to the gear calculated by said gear calculating means.

57. A control as set forth in claim 55, wherein said system includes a torque converter interposed between said engine output and said transmission, and means responsive to a lock-up clutch signal for actuating said torque converter to connect said transmission to said engine for direct mechanical drive when said signal is present and for actuating said torque converter to connect said transmission to said engine for torque converter drive when said signal is not present, said control further comprising:

means responsive to the operation of said transmission in any gear above said minimum gear for generating said lock-up clutch signal,

a timer means for generating a signal of predetermined duration in response to the initiation of a shift of said transmission,

means responsive to the presence of said timer signal for inhibiting the generation of said lock-up clutch signal during the duration of said timer signal.

58. A control as set forth in claim 55, and wherein said system includes a torque converter interposed between said engine output and said transmission, and means responsive to a lock-up clutch signal for actuating said torque converter to connect said transmission to said engine for direct mechanical drive when said signal is present and for actuating said torque converter to connect said transmission to said engine for torque converter drive when said signal is not present, said control further comprising:

means responsive to the operation of said transmission in any gear above said minimum gear for generating said lock-up clutch signal,

means for generating a speed reference signal when said transmission is operating in said minimum gear of said automatic range and for comparing said reference signal with said actual speed signals,

means for generating said lock-up clutch signal when said transmission is operating in said minimum gear and a comparison of said reference signal and said actual speed signals is indicative that the actual speed is greater than said reference speed and for inhibiting the generation of said lock-up clutch signal when said transmission is operating in said minimum gear and a comparison of said reference signal and said actual speed signals is indicative that the actual speed is less than said reference speed.

59. A control as set forth in claim 55, and wherein said system includes a torque converter interposed between said engine output and said transmission, and means responsive to a lock-up clutch signal for actuating said torque converter to connect said transmission to said engine for direct mechanical drive when said signal is present and for actuating said torque converter to connect said transmission to said engine for torque converter drive when said signal is not present, said control further comprising:

means responsive to the operation of said transmission in any gear above said minimum gear for generating said lock-up clutch signal,

a timer means for generating a signal of predetermined duration in response to the initiation of a shift of said transmission,

means responsive to the presence of said timer signal for inhibiting the generation of said lock-up clutch signal during the duration of said timer signal,

means for generating a speed reference signal when said transmission is operating in said minimum gear of said automatic range and for comparing said reference signal with said actual speed signals,

means for generating said lock-up clutch signal when said transmission is operating in said minimum gear and a comparison of said reference signal and said actual speed signals is indicative that the actual speed is greater than said reference speed and for inhibiting the generation of said lock-up clutch signal when said transmission is operating in said minimum gear and a comparison of said reference signal and said actual speed signals is indicative that the actual speed is less than said reference speed.

60. A control as set forth in claim 55 and further including:

a hold switch,

means for generating a hold signal when said hold switch is operated,

means responsive to the presence of said hold signal for inhibiting the shifting of said transmission from said actual gear to a calculated gear for as long as said hold signal is present.

61. A control as set forth in claim 60, and further including:

means for periodically determining the actual speed of said engine and for producing an underspeed signal when the speed of said engine is less than a predetermined limit,

means responsive to the production of said underspeed signal for terminating said hold signal to remove the inhibition of shifting when said underspeed signal is produced.

62. Apparatus aa set forth in claim 52, and further including:

means for counting the number of times that said portions of said gear-calculating means have made gear calculations and for generating a control signal when one of said portions has made a gear calculation with respect to each of a predetermined number of consecutive samplings of said transmission speed,

means responsive to said control signal for shifting said transmission to the gear calculated by said one portion of said gear-calculating means with respect to a selected one of said consecutive samplings of said transmission speed.

63. A control as set forth in claim 62 and further including:

means for periodically determining the speed of said engine and for generating an overspeed signal in the event the speed of said engine exceeds a predetermined limit,

means for continuously generating an actual-plus-one gear signal indicative of one gear higher than said actual gear,

means responsive to the generation of said overspeed signal for immediately upshifting said transmission to the gear indicated by said actual-plus-one gear signal.

64. A control as set forth in claim 62 and further including:

means responsive to the initiation of a shift of said transmission for generating an anti-hunt signal of predetermined duration,

means responsive to the presence of said anti-hunt signal for inhibiting the generation of said control signal by said counting means during the duration of said anti-hunt signal.

65. Apparatus as set forth in claim 52 wherein said gear-calculating means further includes:

a third portion for determining whether the actual speed is below the downshift speed point for said actual gear when said actual gear is above said selected maximum operating gear, and, if so, for calculating the lowest gear to which the transmission may be shifted, said lowest gear being one immediately below a gear which is above said maximum operating gear and has a downshift speed point higher than said actual speed, said lowest gear being either said maximum operating gear or having a downshift speed point lower than said actual speed.

66. Apparatus as set forth in claim 65 and further including:

means responsive to a calculation by said gear calculating means for shifting said transmission to the gear calculated thereby.

67. Apparatus as set forth in claim 65, and further including:

means for counting the number of times that said portions of said gear-calculating means have made gear calculations and for generating a control signal when one of said portions has made a gear calculation with respect to each of a predetermined number of consecutive samplings of said transmission speed,

means responsive to said control signal for shifting said transmission to the gear calculated by said one portion of said gear-calculating means with respect to a selected one of said consecutive samplings of said transmission speed.

68. A control as set forth in claim 66 wherein said transmission has a neutral position and wherein said gear-selecting cane is operable to select said neutral position, said control further including:

means for generating a neutral position command signal in immediate response to selection of said neutral position by said gear-selecting cane,

means responsive to generation of said neutral position command signal for immediately shifting said transmission to said neutral position.

69. A control as set forth in claim 66 and wherein said transmission has a reverse gear lower than said automatic range and wherein said gear-selecting cane is operable to select said reverse gear, said control further including:

means responsive to the selection of said reverse gear by said cane for generating a reverse gear command signal,

means operable when said actual gear is in said automatic range at the time said reverse gear is selected by said cane for delaying generation of said reverse command signal until such time as said transmission has been downshifted to said minimum gear of said automatic range and said actual speed is less than a predetermined low limit,

means responsive to generation of said reverse command signal for shifting said transmission to said reverse gear.

70. A control as set forth in claim 69 and further including:

means for generating an automatic-range command signal in response to selection of any gear in said automatic range by said gear-selecting cane,

means operable when said transmission is operating in said reverse gear at the time of selection by said cane of a gear in said automatic range for delaying generation of said automatic-range command signal until such time as said actual transmission speed is less than a predetermined low limit,

means responsive to generation of said automatic-range command signal for shifting said transmission to said minimum gear of said automatic range.

71. A control as set forth in claim 70 wherein said transmission has a neutral position and wherein said gear-selecting cane is operable to select said neutral position, said control further including:

means for generating a neutral position command signal in immediate response to selection of said neutral position by said gear-selecting cane,

means responsive to generation of said neutral position command signal for immediately shifting said transmission to said neutral position.

72. A control as set forth in claim 66 and wherein said transmission has a first forward gear lower than said automatic range and wherein said gear-selecting cane is operable to select said first forward gear, said control further including:

means responsive to the selection of said first forward gear by said cane for generating a first forward gear command signal,

means operable when said actual gear is in said automatic range at the time said first forward gear is selected by said cane for delaying generation of said first forward command signal until such time as said transmission has been downshifted to said minimum gear of said automatic range and said actual speed is less than a predetermined low limit,

means responsive to generation of said first forward command signal for shifting said transmission to said first forward gear.

73. Apparatus for upshifting a transmission having an automatic range comprising a plurality of gears progressively increasing in ratio from a minimum gear to a maximum gear, said apparatus comprising:

(a) means for generating an upshift speed point signal for each of the gears in said range,

(b) means for generating separate signals indicative of the actual gear that said transmission is in and of selected gears progressively higher than said actual gear,

(c) means for generating a signal indicative of said maximum gear,

(d) means for generating a speed signal indicative of the actual speed of said transmission,

(e) first comparator means for comparing said maximum gear signal separately with said signals for said actual gear and said progressively higher gears,

(f) second comparator means for comparing said transmission speed signal separately with the upshift speed point signals for said actual gear and said progressively higher gears,

(g) gear-determining means responsive to said first and second comparator means for determining the lowest gear wherein both of the following two conditions are met;

(1) such gear is less or equal to said maximum gear,

(2) such gear has an upspeed shift point higher than the actual transmission speed,

(h) means responsive to said gear-determining means for shifting said transmission from said actual gear to said lowest gear determined by said gear-determining means.

74. Apparatus for downshifting a transmission having an automatic range comprising a plurality of gears progressively increasing in ratio from a minimum gear to a maximum gear, said apparatus comprising:

(a) means for generating a downshift speed point signal for each of the gears in said range,

(b) means for generating separate signals indicative of the actual gear that said transmission is in and of selected gears progressively lower than said actual gear,

(c) means for generating a signal indicative of said minimum gear,

(d) means for generating a speed signal indicative of the actual speed of said transmission,

(e) first comparator means for comparing said minimum gear signal separately with said signals for said actual gear and said progressively lower gears,

(f) second comparator means for comparing said transmission speed signal separately with the downshift speed point signals for said actual gear and said progressively higher gears,

(g) gear-determining means responsive to said first and second comparator means for determining the highest gear wherein both of the following two conditions are met;

(1) such gear is greater or equal to said minimum gear,

(2) such gear has a downshift shift point lower than the actual transmission speed.

(h) means responsive to said gear-determining means for shifting said transmission from said actual gear to said highest gear determined by said gear-determining means.

75. A control as set forth in claim 74 and further including:

means for generating a malfunction signal in response to a loss of said actual speed signal,

means responsive to the generation of said malfunction signal for inhibiting shifting of said transmission from said actual gear to the gear calculated by said gear calculating means.

76. A control for a system including an engine and a transmission coupled to the output of said engine, said transmission having a plurality of gears in an automatic range which progressively increase in ratio from a preselected minimum automatic gear, said transmission having associated therewith an operator-controllable gear-selecting cane for selecting any of the gears of said transmission, said control comprising:

means for generating an actual gear signal uniquely indicative of the actual gear existing in said transmission and for maintaining said signal until such time as said transmission is shifted from such gear,

means for generating a cane signal uniquely indicative of the gear selected by said gear-selecting cane and for maintaining said signal until such time as the gear selection is changed,

means for establishing a series of successive operating cycles for said control,

means for generating an actual speed signal once for each cycle of operation and for maintaining said signal during the cycle for which it is generated, each such speed signal being indicative of the actual transmission speed when such speed signal is generated,

means for producing gear test signals indicative of said actual gear and of gears progressively higher than said actual gear,

a first comparator means for comparing and determining the relationship of selected of said gear test signals to said cane signal,

means responsive to said gear test signals for producing predetermined upshift speed point signals for each one of said gear test signals,

a second comparator means for comparing and determining the relationship of produced speed point signals to an actual speed signal,

an upshift test means operable during a cycle of operations and responsive to said first and second comparator means for (1) determining that an upshift condition exists when said first comparator means determines that said actual gear is below the gear selected by said cane and said second comparator means determines that the actual speed is greater than the upshift speed point for said actual gear, and for (2) determining the desired and lowest gear above said actual gear which either said first comparator means determines is the same as the gear selected by said cane or said second comparator means determines to have an upshift speed point above said actual speed, and for (3) generating a new gear signal during said cycle of operation when said desired gear has been determined.

77. A control as set forth in claim 76, and further including:

means responsive to said upshift test means and responsive to the generation of a new gear signal by said test means for shifting said transmission from said actual gear to the desired gear determined by said test means.

78. A control as set forth in claim 76, and further including:

storage means operatively associated with said automatic upshift and automatic downshift test means and responsive to the generation of a new gear signal thereby for storing a gear signal indicative of the desired gear determined by said test means,

counting means operatively associated with said upshift test means for generating a control signal when said test means has determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

means responsive to the generation of said control signal for selecting one of the desired gear signals stored in said storage means and for shifting said transmission from said actual gear to the desired gear indicated by the selected desired gear signal.

79. A control as set forth in claim 78, and further including:

means for periodically determining the actual speed of said engine and for producing an overspeed signal if such speed exceeds a predetermined limit,

means responsive to said overspeed signal for causing an immediate upshift of said transmission.

80. A control for a system including an engine and a transmission coupled to the output of said engine, said transmission having a plurality of gears in an automatic range which progressively increase in ratio from a preselected minimum automatic gear to a maximum gear, said control comprising:

means for generating an actual gear signal uniquely indicative of the actual gear existing in said transmission and for maintaining said signal until such time as said transmission is shifted from such gear,

means for generating and maintaining a minimum gear signal uniquely indicative of said minimum gear of said automatic gear,

means for establishing a series of successive operating cycles for said control,

means for generating an actual speed signal once for each cycle of operation and for maintaining said signal during the cycle for which it is generated, each such speed signal being indicative of the actual transmission speed when such speed signal is generated,

means for producing gear test signals indicative of said actual gear and of gears progressively lower than said actual gear,

a first comparator means for comparing and determining the relationship of selected of said gear test signals to said minimum gear signal,

means responsive to said gear test signals for producing predetermined downshift speed point signals for each one of said gear test signals,

a second comparator means for comparing and determining the relationship of produced speed point signals to an actual speed signal,

a downshift test means operable during a cycle of operations and responsive to said first and second comparator means for (1) determining that a downshift condition exists when said first comparator means determines that said actual gear is above said minimum gear and said second comparator means determines that the actual speed is below the downshift speed point for said actual gear, and for (2) determining the desired and highest gear below said actual gear which either said first comparator means determines is the same as said minimum gear or said second comparator means determines to have a downshift speed point below said actual speed, and for (3) generating a new gear signal during said cycle of operation when said desired gear has been determined.

81. A control as set forth in claim 80, and further including:

means responsive to said downshift test means, and responsive to the generation of a new gear signal by said test means for shifting said transmission from said actual gear to the desired gear determined by said test means.

82. A control as set forth in claim 81, and further including:

a hold switch,

means for generating a hold signal when said hold switch is operated,

means responsive to the presence of said hold signal for inhibiting the shifting of said transmission from said actual gear for as long as said hold signal is present.

83. A control as set forth in claim 82, and further including:

means for periodically determining the actual speed of said engine and for producing an underspeed signal when the speed of said engine is less than a predetermined limit,

means responsive to the production of said underspeed signal for terminating said hold signal to remove the inhibition of shifting when said underspeed signal is produced.

84. A control as set forth in claim 80, and further including:

storage means operatively associated with said downshift test means and responsive to the generation of a new gear signal thereby for storing a gear signal indicative of the desired gear determined by said test means,

counting means operatively associated with said downshift test means for generating a control signal when said test means has determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

means responsive to the generation of said control signal for selecting one of the desired gear signals stored in said storage means and for shifting said transmission from said actual gear to the desired gear indicated by the selected desired gear signal.

85. A control for a system including an engine and a transmission coupled to the output of said engine, said transmission having a plurality of gears in an automatic range which progressively increase in ratio from a preselected minimum automatic gear, said transmission having associated therewith an operator-controllable gear-selecting cane for selecting any of the gears of said transmission in said range, said control comprising:

means for generating an actual gear signal uniquely indicative of the actual gear existing in said transmission and for maintaining said signal until such time as said transmission is shifted from such gear,

means for generating a cane signal uniquely indicative of the gear selected by said gear-selecring cane and for maintaining said signal until such time as the gear selection is changed,

means for generating and maintaining a minimum gear signal uniquely indicative of said minimum gear of said automatic gear,

means for establishing a series of successive operating cycles for said control,

means for generating an actual speed signal once for each cycle of operation and for maintaining said signal during the cycle for which it is generated, each such speed signal being indicative of the actual transmission speed when such speed signal is generated,

means for producing gear test signals indicative of said actual gear and of gears progressively higher and lower than said actual gear,

a first comparator means for comparing and determining the relationship of selected of said gear test signals to said cane signal,

a second comparator means for comparing and determining the relationship of selected of said gear test signals to said minimum gear signal,

means responsive to said gear test signals for producing predetermined upshift and downshift speed point signals for each one of said gear test signals,

a third comparator means for comparing and determining the relationship of produced speed point signals to an actual speed signal,

an automatic upshift test means operable during a cycle of operations and responsive to said first and third comparator means for (1) determining that an upshift condition exists when said first comparator means determines that said actual gear is below the gear selected by said cane and said third comparator means determines that the actual speed is greater than the upshift speed point for said actual gear, and for (2) determining the desired and lowest gear above said actual gear which either said first comparator means determines is the same as the gear selected by said cane or said third comparator means determines to have an upshift speed point above said actual speed, and for (3) generating a new gear signal during said cycle of operation when said desired gear has been determined,

an automatic downshift test means operable during a cycle of operations and responsive to said second and third comparator means for (1) determining that a downshift condition exists when said second comparator means determines that said actual gear is above said minimum gear and said third comparator means determines that the actual speed is below the downshift speed point for said actual gear, and for (2) determining the desired and highest gear below said actual gear which either said second comparator means determines is the same as said minimum gear or said third comparator means determines to have a downshift speed point below said actual speed, and for (3) generating a new gear signal during said cycle of operation when said desired gear has been determined.

86. A control as set forth in claim 85 and further including:

means responsive to said automatic upshift test means and said automatic downshift test means, and responsive to the generation of a new gear signal by one of said test means for shifting said transmission from said actual gear to the desired gear determined by said one test means.

87. A control as set forth in claim 85, and further including:

storage means operatively associated with said automatic upshift and downshift test means and responsive to the generation of a new gear signal by one of said test means for storing a gear signal indicative of the desired gear determined by said test means,

counting means operatively associated with said automatic upshift and automatic downshift test means for generating a control signal when either one of said test means has itself determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

means responsive to the generation of said control signal for selecting one of the desired gear signals stored in said storage means and for shifting said transmission from said actual gear to the desired gear indicated by the selected desired gear signal.

88. A control as set forth in claim 85, and further including:

a forced downshift test means operable during a cycle of operation of said control and responsive to said first and third comparator means for (1) determining that a forced downshift shift condition exists when said first comparator means determines that the actual gear is higher than the gear selected by said cane, and when said third comparator determines that the actual speed is below the downshift speed point for said actual gear, and for (2) determining from the determinations of said first and third comparator means the desired and highest gear below the actual gear which is either the same as the gear selected by said cane or which has a downshift speed point lower than the actual transmission speed, and for (3) generating a new gear signal during said cycle of operation when said desired gear is determined.

89. A control as set forth in claim 88 and further including:

means responsive to said forced downshift test means, said automatic upshift test means and said automatic downshift test means, and responsive to the generation of a new gear signal by one of said test means for shifting said transmission from said actual gear to the desired gear determined by said one test means.

90. A control as set forth in claim 88, and further including:

storage means operatively associated with said forced downshift, automatic upshift and automatic downshift test means and responsive to the generation of a new gear signal by one of said test means for storing a gear signal indicative of the desired gear determined by said test means,

counting means operatively associated with said forced downshift, automatic upshift and automatic downshift test means for generating a control signal when any one of said test means has itself determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

means responsive to the generation of said control signal for selecting one of the desired gear signals stored in said storage means and for shifting said transmission from said actual gear to the desired gear indicated by the selected desired gear signal.

91. A control for a system including an engine and a transmission coupled to the output of said engine, said transmission having a plurality of gears in an automatic range which progressively increase in ratio from a preselected minimum automatic gear, said transmission having associated therewith an operator-controllable gear-selecting cane for selecting any of the gears of said transmission, said control comprising:

means for generating an actual gear signal uniquely indicative of the actual gear existing in said transmission and for maintaining said signal until such time as said transmission is shifted from such gear,

means for generating a cane signal uniquely indicative of the gear selected by said gear-selecting cane and for maintaining said signal until such time as the gear selection is changed,

means for generating and maintaining a minimum gear signal uniquely indicative of said minimum gear of said automatic gear,

means for establishing a series of successive operating cycles for said control,

means for generating an actual speed signal once for each cycle of operation and for maintaining said signal during the cycle for which it is generated, each such speed signal being indicative of the actual transmission speed when such speed signal is generated,

gear signal stepping means for producing a gear-indicative signal at the output thereof and operative when energized to incrementally increase or decrease said gear-indicative signal to indicate progressively higher or lower gears, respectively,

a first comparator means for comparing and determining the relationship between said gear-indicative signal of said stepping means and said cane signal,

a second comparator means for comparing and determining the relationship between said gear-indicative signal of said stepping means and said minimum gear signal,

means responsive to the gear-indicative signals of said stepping means for producing predetermined upshift and downshift speed point signals for each gear indicated by such gear-indicating signals,

a third comparator means for comparing and determining the relation between a produced speed point signal and one of said actual speed signals,

means operable in each cycle of operation of said control for initially setting said stepping means to produce a gear-indicative signal which is indicative of said actual gear,

an automatic upshift test means operable during a cycle of operation of said control for (1) determining the existence of an upshift shift condition and energizing said stepping means to increase said gear-indicative signal by one each time during a cycle of operation that said first comparator determines that the gear then indicated by said stepping means is lower than the gear selected by said cane and said third comparator means determines that said actual speed is above the upshift speed point for said gear then indicated by said stepping means, and (2) for generating a new gear signal during the same cycle of operation and when said stepping means has been increased at least once and either said first comparator determines that the gear then indicated by said stepping means is the same as the gear selected by said cane, or said third comparator determines that said actual speed is less than the upshift speed point for said gear then indicated by said stepping means,

an automatic downshift test means operable during a cycle of operation of said control for (1) determining the existence of a downshift shift condition and energizing said stepping means to decrease said gear-indicative signal by one each time during a cycle of operation that said second comparator determines that the gear then indicated by said stepping means is greater than said minimum gear and said third comparator means determining that said actual speed is below the downshift speed point for said gear then indicated by said stepping means, and (2) for generating a new gear signal during the same cycle of operation and when said stepping means has been increased at least once and either said second comparator determines that the gear then indicated by said stepping means is the same as said minimum gear, or said third comparator determines that said actual speed is greater than the downshift speed point for said gear then indicated by said stepping means.

92. A control as set forth in claim 91, and wherein all of said means for generating signals indicative of gears and signals indicative of actual speed and speed points each include means for generating such signals in binary coded form.

93. A control as set forth in claim 91 wherein said means for producing speed point signals comprises an addressable and programmable memory matrix, said matrix being addressed by said gear-indicative signals of said stepping means, and said memory matrix being programmed with predetermined upshift and downshift speed points for each of the gears of said automatic range whereby upshift and downshift speed point signals are producible for each, and in accordance with, the gear-indicative signal addressed to said matrix.

94. A control as set forth in claim 91 wherein said gear signal stepping means comprises a binary up/down counter.

95. A control as set forth in claim 91, and further including:

storage means responsive to the generation of a new gear signal for storing the calculated gear-indicative signal of said stepping means which is present when said new gear signal is generated,

means for shifting said transmission from said actual gear to the gear indicated by the calculated gear-indicative signal stored in said storage means.

96. A control as set forth in claim 95 wherein said storage means comprises a plurality of serially arranged shift registers, the first of which is connected to receive gear-indicative signals from said stepping means, and includes means for shifting the calculated gear-indicative signals in said registers from one register to a successive register in response to the generation of a new gear signal,

and further including means operable when said control signal of said counting means has been generated for selecting the calculated gear-indicative signal of one of said registers as indicative of the gear to which said transmission is to be shifted.

97. A control as set forth in claim 95 and further including:

a hold switch,

means for generating a hold signal when said hold switch is operated,

means responsive to the presence of said hold signal for inhibiting the shifting of said transmission from said actual gear for as long as said hold signal is present.

98. A control as set forth in claim 97, and further including:

means for periodically determining the actual speed of said engine and for producing an underspeed signal when the speed of said engine is less than a predetermined limit,

means responsive to the production of said underspeed signal for terminating said hold signal to remove the inhibition of shifting when said underspeed signal is produced.

99. A control as set forth in claim 95 and further including:

means responsive to each actual speed signal for generating a malfunction signal in the event a speed signal is indicative that the actual transmission speed is less than a predetermined low reference limit,

means responsive to the generation of said malfunction signal for inhibiting shifting of said transmission to the gear indicated by the calculated gear-indicative signal stored in said storage means.

100. A control as set forth in claim 95, and wherein said system includes a torque converter interposed between said engine output and said transmission, and means responsive to a lock-up clutch signal for actuating said torque converter to connect said transmission to said engine for direct mechanical drive when said signal is present and for actuating said torque converter to connect said transmission to said engine for torque converter drive when said signal is not present, said control further comprising:

means responsive to the operation of said transmission in any gear above said minimum gear for generating said lock-up clutch signal,

means responsive to the presence of said timer signal for inhibiting the generation of said lock-up clutch signal during the duration of said timer signal,

means for generating a speed reference signal when said transmission is operating in said minimum gear and for applying said speed reference to said third comparator means for comparison of said speed reference signal with each said actual speed signal,

means responsive to said second and third comparator means for (a) generating said lock-up clutch signal when said second comparator means determines that said actual gear is the same as said minimum gear and said third comparator means determines that the actual speed is greater than said reference speed, and (b) for inhibiting generation of said lock-up clutch signal when said second comparator means determines that said actual gear is the same as said minimum gear and said third comparator determines that the actual speed is lower than said reference speed.

101. A control as set forth in claim 95, and wherein said system includes a torque converter interposed between said engine output and said transmission, and means responsive to a lock-up clutch signal for actuating said torque converter to connect said transmission to said engine for direct mechanical drive when said signal is present and for actuating said torque converter to connect said transmission to said engine for torque converter drive when said signal is not present, said control further comprising:

means responsive to the operation of said transmission in any gear above said minimum gear for generating said lock-up clutch signal,

a timer means for generating a signal of predetermined duration in response to the initiation of a shift of said transmission,

means responsive to the presence of said timer signal for inhibiting the generation of said lock-up clutch signal during the duration of said timer signal,

means for generating a speed reference signal when said transmission is operating in said minimum gear of said automatic range and for comparing said reference signal with said actual speed signals,

means for generating said lock-up clutch signal when said transmission is operating in said minimum gear and a comparison of said reference signal and said actual speed signals is indicative that the actual speed is greater than said reference speed and for inhibiting the generation of said lock-up clutch signal when said transmission is operating in said minimum gear and a comparison of said reference signal and said actual speed signals is indicative that the actual speed is less than said reference speed.

102. A control as set forth in claim 91, and further including:

means responsive to the generation of a new gear signal for storing the gear-indicative signal of said stepping means which is present when said new gear signal is generated,

a fourth comparator means for comparing and determining the relationship between said stored gear-indicative signal and said actual gear signal and for producing an upshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is higher than said actual gear and for producing a downshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is lower than said actual gear,

means for applying the stored gear-indicative signal to said fourth comparator means,

means for upshifting said transmission in response to the presence of said upshift signal and for downshifting said transmission in response to the presence of said downshift signal.

103. A control as set forth in claim 102, and wherein said system includes a torque converter interposed between said engine output and said transmission, and means responsive to a lock-up clutch signal for actuating said torque converter to connect said transmission to said engine for direct mechanical drive when said signal is present and for actuating said torque converter to connect said transmission to said engine for torque converter drive when said signal is not present, said control further comprising:

means responsive to the operation of said transmission in any gear above said minimum gear for generating said lock-up clutch signal,

a timer means responsive to the production of either an upshift signal or a downshift signal for generating a signal of predetermined duration,

means responsive to the presence of said timer signal for inhibiting the generation of said lock-up clutch signal during the duration of said timer signal.

104. A control as set forth in claim 102, and further including:

means responsive to the production of either an upshift signal or a downshift signal for generating an anti-hunt signal of predetermined duration,

means responsive to the presence of said anti-hunt signal for inhibiting the determination of a new gear to which said transmission should be shifted until after the end of said anti-hunt signal.

105. A control as set forth in claim 91, and further including:

storage means operatively associated with said stepping means for storing the gear-indicative signal of said stepping means which is present during one of a predetermined number of successive operating cycles of said control and which is present during said one cycle at the time said new gear signal is generated during that cycle,

counting means operatively associated with said automatic upshift and automatic downshift test means for generating a control signal when either one of said test means has itself determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

means responsive to the generation of said control signal for shifting said transmission from said actual gear to the gear indicated by the gear-indicative signal stored in said storage means.

106. A control as set forth in claim 105, and further including:

means for periodically determining the speed of said engine and for generating an overspeed signal in the event the speed of said engine exceeds a predetermined limit,

means for continuously generating a gear signal indicative of one gear higher than said actual gear,

means responsive to the generation of said overspeed signal for immediately applying said last-referred-to gear signal to said fourth comparator means in place of said stored gear-indicative signal.

107. A control as set forth in claim 91, and further including:

storage means operatively associated with said stepping means for storing the gear-indicative signal of said stepping means which is present during one of a predetermined number of successive operating cycles of said control and which is present during said one cycle of the time said new gear signal is generated during that cycle,

counting means operatively associated with said automatic upshift and automatic downshift test means for generating a control signal when either one of said test means has itself determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

a fourth comparator means for comparing and determining the relationship between said stored gear-indicative signal and said actual gear signal and for producing an upshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is higher than said actual gear and for producing a downshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is lower than said actual gear,

means for applying the stored gear-indicative signal to said fourth comparator means when said control signal of said counting means is generated,

means for upshifting said transmission in response to the presence of said upshift signal and for downshifting said transmission in response to the presence of said downshift signal.

108. Acontrol as set forth in claim 91 and further including:

a forced downshift test means operable during a cycle of operation of said control for (1) determining the existence of a forced downshift shift condition and energizing said stepping means to decrease said gear-indicative signal by one each time during a cycle of operation that said first comparator means determines that the gear then indicated by said stepping means is higher than the gear selected by said cane and said third comparator means determines that said actual speed is below the downshift speed point for said gear then indicated by said stepping means; and

(2) for generating a new gear signal during the same cycle of operation of said control when either said first comparator means determines that the gear then indicated by said stepping means is the same as the gear selected by said cane, or said third comparator means determines that said actual speed is higher than the downshift speed point for the gear then indicated by said stepping means.

109. A control as set forth in claim 108, and further including:

means for inhibiting operation of said upshift test means during a cycle of operation of said control when said first comparator means determines that the gear initially indicated by said stepping means is higher than the gear selected by said cane.

110. A control as set forth in claim 108, and further including:

storage means responsive to the generation of a new gear signal for storing the gear-indicative signal of said stepping means which is present when said new gear signal is generated,

means for shifting said transmission from said actual gear to the gear indicated by the gear-indicative signal stored in said storage means.

111. A control as set forth in claim 110, wherein said transmission has a neutral position and wherein said gear-selecting cane is operable to select said neutral position, said control further including:

means for generating a neutral position command signal in immediate response to the selection of said neutral position by said gear-selecting cane,

means reponsive to the generation of said neutral position command signal for immediately shifting said transmission to said neutral position.

112. A control as set forth in claim 110, and wherein said transmission includes a reverse gear and wherein said gear-selecting cane is operable to select said reverse gear, said control further including:

means responsive to the selection of said reverse gear by said cane for generating a reverse gear command signal,

means for generating a low speed limit signal when the actual speed signal is indicative that the actual transmission speed is less than a predetermined low limit,

means operable when said actual gear is in said automatic range at the time said reverse gear is selected by said cane and responsive to said second comparator means and said low speed limit signal for delaying generation of said reverse command signal until such time as said second comparator means determines that said actual gear is the same as said minimum gear and said low speed limit signal has been generated,

means responsive to the generation of said reverse command signal for shifting said transmission to said reverse gear.

113. A control as set forth in claim 112, and further including:

means for generating an automatic-range command signal in response to selection of any gear in said automatic range by said gear-selecting cane,

means operable when said transmission is operating in said reverse gear for delaying generation of said automatic-range command signal until such time as said low speed limit signal is generated,

means responsive to the generation of said automatic-range signal for shifting said transmission from said reverse gear to said minimum gear of said automatic range.

114. A control as set forth in claim 113, wherein said transmission has a neutral position and wherein said gear-selecting cane is operable to select said neutral position, said control further including:

means for generating a neutral position command signal in immediate response to the selection of said neutral position by said gear-selecting cane,

means responsive to the generation of said neutral position command signal for immediately shifting said transmission to said neutral position.

115. A control as set forth in claim 110, and wherein said transmission includes a first forward gear lower than said automatic range and wherein said gear-selecting cane is operable to select said first forward reverse gear, said control further including:

means responsive to the selection of said first forward gear by said cane for generating a first forward gear command signal,

means for generating a low speed limit signal when the actual speed signal is indicative that the actual transmission speed is less than a predetermined low limit,

means operable when said actual gear is in said automatic range at the time said first forward gear is selected by said cane and responsive to said second comparator means and said low speed limit signal for delaying generation of said first forward command signal until such time as said second comparator means determines that said actual gear is the same as said minimum gear and said low speed limit signal has been generated,

means responsive to the generation of said first forward command signal for shifting said transmission to said first forward gear.

116. A control as set forth in claim 108, and further including:

means responsive to the generation of a new gear signal for storing the gear-indicative signal of said stepping means which is present when said new gear signal is generated,

a fourth comparator means for comparing and determining the relationship between said stored gear-indicative signal and said actual gear signal and for producing an upshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is higher than said actual gear and for producing a downshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is lower than said actual gear,

means for applying the stored gear-indicative signal to said fourth comparator means,

means for upshifting said transmission in response to the presence of said upshift signal and for downshifting said transmission in response to the presence of said downshift signal.

117. A control as set forth in claim 108, and further including:

storage means operatively associated with said stepping means for storing the gear-indicative signal of said stepping means which is present during one of a predetermined number of successive operating cycles of said control and which is present during said one cycle at the time said new gear signal is generated during that cycle,

counting means operatively associated with said forced downshift, automatic upshift and automatic downshift test means for generating a control signal when any one of said test means has itself determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

means responsive to the generation of said control signal for shifting said transmission from said actual gear to the gear indicated by the gear-indicative signal stored in said storage means.

118. A control as set forth in claim 108, and further including:

storage means operatively associated with said stepping means for storing the gear-indicative signal of said stepping means which is present during one of a predetermined number of successive operating cycle of said control and which is present during said one cycle at the time said new gear signal is generated during that cycle,

counting means operatively associated with said forced downshift, automatic upshift and automatic downshift test means for generating a control signal when any one of said test means has itself determined the existence of a shift condition in each of a predetermined number of successive cycles of operation of said control,

a fourth comparator means for comparing and determining the relationship between said stored gear-indicative signal and said actual gear signal and for producing an upshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is higher than said actual gear and for producing a downshift signal when, and for as long as, the gear indicated by said stored gear-indicative signal is lower than said actual gear,

means for applying the stored gear-indicative signal to said fourth comparator means when said control signal of said counting means is generated,

means for upshifting said transmission in response to the presence of said upshift signal and for downshifting said transmission in response to the presence of said downshift signal.

119. A control as set forth in claim 118, wherein said transmission has a neutral position and wherein said gear-selecting cane is operable to select said neutral position, said control further including:

said means for generating an actual gear signal including means for generating an actual gear signal indicative of said neutral position of said transmission and indicative of said neutral position being lower than the gears of said automatic range,

means responsive to the selection of said neutral position by said gear-selecting cane for generating a gear-indicative signal indicative of said neutral position,

means for generating a neutral position command signal in immediate response to the selection of said neutral position by said gear-selecting cane,

means responsive to the generation of said neutral position command signal for immediately shifting said transmission to said neutral position,

means responsive to the generation of said neutral command signal for immediately applying said gear-indicative signal indicative of neutral position to said fourth comparator means in lieu of said stored gear-indicative signal for comparison of said neutral gear-indicative signal with said actual gear signal.

120. A control as set forth in claim 118, and wherein said transmission includes a reverse gear lower than said automatic range and wherein said gear-selecting cane is operable to select said reverse gear, said control further including:

said means for generating an actual gear signal further includes means for generating an actual gear signal indicative of said reverse gear when said transmission is actually in such gear,

means for generating a reverse gear-indicative signal in response to selection of such gear by said gear-selecting cane,

means for generating a reverse gear command signal in response to selection of such gear by said gear-selecting cane,

means for generating a low speed limit signal when the actual speed signal is indicative that the actual transmission speed is less than a predetermined low limit,

means operable when said actual gear is in said automatic range at the time said reverse gear is selected by said cane and responsive to said second comparator means and said low speed limit signal for delaying generation of said reverse command signal until such time as said second comparator means determines that said actual gear is the same as said minimum gear and said low speed limit signal has been generated,

means responsive to the generation of said reverse command signal for applying said reverse gear-indicative signal to said fourth comparator means in lieu of a stored gear-indicative signal for comparison of said reverse gear-indicative signal with said actual gear signal.

121. A control as set forth in claim 120, and further including:

means for generating an automatic-range command signal in response to selection of any gear in said automatic range by said gear-selecting cane,

means operable when said transmission is operating in said reverse gear for delaying generation of said automatic-range command signal until such time as said low speed limit signal is generated,

means responsive to the generation of said automatic-range signal for shifting said transmission from said reverse gear to said minimum gear of said automatic range,

means responsive to the generation of said automatic-range signal for applying said minimum gear signal to said fourth comparator means for comparison with said actual gear signal.

122. A control as set forth in claim 121, wherein said transmission has a neutral position and wherein said gear-selecting cane is operable to select said neutral position, said control further including:

said means for generating an actual gear signal including means for generating an actual gear signal indicative of said neutral position of said transmission and indicative of said neutral position being lower than the gears of said automatic range,

means responsive to the selection of said neutral position by said gear-selecting cane for generating a gear-indicative signal indicative of said neutral position,

means for generating a neutral position command signal in immediate response to the selection of said neutral position by said gear-selecting cane,

means responsive to the generation of said neutral position command signal for immediately shifting said transmission to said neutral position,

means responsive to the generation of said neutral command signal for immediately applying said gear-indicative signal indicative of neutral position to said fourth comparator means in lieu of said stored gear-indicative signal for comparison of said neutral gear-indicative signal with said actual gear signal.

123. A control as set forth in claim 118, and wherein said transmission includes a first forward gear lower than said automatic range and wherein said gear-selecting cane is operable to select said first forward gear, said control further including:

said means for generating an actual gear signal further includes means for generating an actual gear signal indicative of said first forward gear when said transmission is actally in such gear,

means for generating a first forward gear-indicative signal in response to selection of such gear by said gear-selecting cane,

means for generating a first forward gear command signal in response to selection of such gear by said gear-selecting cane,

means for generating a low speed limit signal when the actual speed signal is indicative that the actual transmission speed is less than a predetermined low limit,

means operable when said actual gear is in said automatic range at the time said first forward gear is selected by said cane and responsive to said second comparator means and said low speed limit signal for delaying generation of said first forward command signal until such time as said second comparator means determines that said actual gear is the same as said minimum gear and said low speed limit signal has been generated,

means responsive to the generation of said first forward command signal for applying said first forward gear-indicative signal to said fourth comparator means in lieu of a stored gear-indicative signal for comparison of said first forward gear-indicative signal with said actual gear signal.