ENCODING TECHNIQUE FOR ENABLING A DEVICE TO PROCESS DIFFERENT TYPES OF DIGITAL INFORMATION TRANSMITTED ALONG A SINGLE INFORMATION CHANNEL

• US 3,827,026 A
• Filed: 01/04/1971
• Issued: 07/30/1974
• Est. Priority Date: 01/04/1971
• Status: Expired due to Term

• Current Assignee: G. R. Viswanathan
• Original Assignee: G. R. Viswanathan
• Inventors: Viswanathan, G. R.
• Primary Examiner(s): Pitts, Harold I.
• Application Number:
  US05/103,409
• Time in Patent Office: 1,303 Days
• Field of Search: 340/167R,167A 178/66R 179/15R 328/112R
• US Class Current: 370/212
• CPC Class Codes: H04J 7/00 Multiplex systems in which the amplitudes or durations of the signals in individual channels are characteristic of those channels
• CPC Class Codes: H04L 25/00 Baseband systems
• CPC Class Codes: H04L 5/1423 for simultaneous baseband signals
• CPC Class Codes: H04N 7/148 Interfacing a video terminal to a particular transmission medium, e.g. ISDN

Abstract

A data processing system includes a first device which transmits different types of pulse coded digital information along a single channel to a second device for separation and distribution to a number of different outputs. The different types of digital information transmitted are encoded with different pulse widths. The pulse widths for the different types of information are selected to provide highly reliable data transmission. The second device includes a receive section which has a plurality of detectors. Each of these detectors operate to detect only the pulse coded digital information encoded with predetermined pulse widths and pass them to its output. The system accommodates bidirectional transmission and processing of the encoded digital information by including like transmit and receive sections within each device.

Claims

1. A method of communicating different types of digital information between a first device and a second device along a single information channel comprising the steps of:

a. encoding each different type of digital information to be processed by said first and second devices into groups of coded pulses having the same predetermined pulse width within a range of pulse widths, each said pulse width being different from the ranges of pulse widths of pulses representative of the other types of digital information;

b. transmitting said pulses along said single channel, said groups of pulses coded to represent each different type of digital information, each group being encoded with the same predetermined pulse width within said range of pulse widths;

c. said first and second devices detecting the pulses of the groups of pulses corresponding to each of the different types of digital information received on the basis of their respective pulse width; and

d. distributing predetermined ones of said groups of pulses corresponding to said different types of said digital information detected to different ones of a predetermined number of output terminals within said first and second devices.

2. A method of transmitting different types of digital information along a single cable to a device for processing comprising the steps of:

a. assigning a range of different predetermined pulse widths to each different type of digital informaton to be processed by said device;

b. transmitting along said single cable to said device trains of pulses, each train coded to represent said each different type of digital information in pulse coded form and encoded in accordance with said assigned pulse widths; and

c. separating said each train corresponding to each different type of pulse coded digital information on the basis of said assigned pulse widths for distribution to a different predetermined one of a number of output terminals included within said device for subsequent processing by said device.

3. A method of transmitting different classes of digital information along a single cable to a device for processing comprising the steps of:

a. assigning to each of a plurality of pulses coded to represent each one of a number of said different classes of digital information a pulse width from one of a plurality of groups of pulse widths selected to provide a range of unassignable pulse widths between said each group so as to enable accurate detection of said each of a plurality of pulses corresponding to said digital information represented by the assigned pulse width;

b. transmitting along said cable said each of said plurality of pulses coded to be representative of said digital information in pulse coded form characterized by said assigned pulse widths to said device; and

c. detecting said plurality of pulses representative of each different type of pulse coded information on the basis of pulse width for distribution to a different predetermined one of a number of output terminals included within said device.

4. In a transmission sysTem comprising:

transmit means;

receive means;

a bus for interconnecting said transmit means to said receive means;

said trasnmit means coupled to said bus and including a plurality of input means each for applying to said bus for transmission to said receive means pulses coded to represent different type of digital information, all of the pulses of each type being coded with the same pulse width within a range of pulse widths different from the range of pulse widths of the different types of digital information being applied to the other ones of said plurality of input means; and

said receive means coupled to said bus and including a plurality of detectors each including input and output means, each of said input means being connected to receive said transmitted digital information pulses and each being operative to pass to each said output means only those pulses corresponding to a different type of digital information characterized by predetermined pulse widths within said range of pulse widths.

5. The system of claim 4 wherein said bus includes twisted pair of conductors and said transmit means is directly coupled to said bus.

6. The system of claim 5 wherein said transmit means includes a driver means including a first pair of transistors;

a current source, said current source being connected to the emitter electrodes of said first pair of transistors;

a second pair of transistors opposite in conductivity to said first transistor pair;

a current sink, said current sink being connected in common to the emitter electrodes of said second transistor pair;

input diode network means connected across the base electrodes of said first transistors pair;

first and second like voltage translation means each connecting the base electrodes of a different one of the transistors of said first pair to the base electrode of a different one of the transistors of said second pair; and

, first means for connecting the collector electrodes of the translation means connected pair of transistors in common to one of the conductors of said twisted pair;

means for connecting the collector electrodes of the other pair of translation means connected transistors to the other conductor of said twisted pair whereby said driver in response to an input pulse applied to said base electrodes and to said diode network means conditions predetermined transistors of said first and second pair to apply positive and negative voltages to said twisted conductor pair and in the absence of said pulse conditions the remaining two transistors of said first and said second pairs to apply voltages opposite in polarity to said positive and negative voltages to said twisted conductor pair.

7. The system of claim 6 wherein said first and second voltage translation means each include zener diodes.

8. The system according to claim 4 wherein said receive means further includes delay means including an input terminal and a plurality of output terminals, each of said output terminals arranged to provide an output pulse delayed from the pulse applied to said input terminal by a different predetermined amount;

each of said detectors including pulse generating means coupled to said detector input means and logic means coupled to predetermined ones of said delay output terminals and to said pulse generating means, said pulse generating means being operative to generate a pulse having a predetermined pulse width in response to the leading edge of each pulse applied to said detector input means and said logic means being coupled to be responsive to said pulses applied to said detector input means and the pulses produced by said pulse generating means so as to logically combine them in a manner to pass only digital information pulses within said range of said pulse widths to said detector output means.

9. The system of claim 8 wherein each of said logic means includes means for receiving a common control input for either enabling or diabling said detectors simultaneoUsly.

10. The system of claim 8 wherein said logic means includes AND gates.

11. The system of claim 8 wherein said delay means includes a delay line.

12. The system of claim 8 wherein first and second detectors of said plurality of detectors are connected in series, said input means and said logic means of said first detector being coupled to said input terminal of said delay means, said logic means of said first detector being coupled to a predetermined one of said output terminals of said delay means, and to said input terminal and logic means of said second detector, said second detector being operative to pass to said output means pulses within a range of widths representative of only a predetermined one of said two types of digital information by said logic means combining pulses generated by said pulse generating means and pulses passed to said output means to said first detector.

13. The system of claim 12 wherein said predetermined one of said types of digital information is encoded pulse widths longer than pulses within the range of pulse widths of said digital information pulses applied to said first detector and said pulse generating means of said second detector includes means for generating pulses whose widths are longer than said range of pulse widths.

14. In a transmission system comprising:

transmit means;

receive means;

a bus interconnected to said transmit means at one end and to receive means at the other end of bidirectional transmission of different types of digital information;

said transmit means including a plurality of input terminal means each coupled to receive groups of pulses coded to represent one of a number of different types of pulse coded digital information and having a predetermined one of a plurality of different pulse widths, each different pulse width being characteristic of a predetermined type of digital information and driver means coupled to said plurality of input terminal means for applying said digital information pulses to said bus; and

, said receive means including a plurality of detectors, each detector including input means and output means, each of said input means being connected to receive said digital information pulses, each of said detectors including pulse generating means for generating in response to each received pulse a signal whose pulse width defines the type of digital information being detected by said detector, and each of said detectors including means for comparing each said pulse generated signal with each of said digital information pulses so as to produce a signal at said output means only in response to digital information pulses whose width is within a range of pulse widths characteristics of said type of information detectable by said detector.

15. The system of claim 14 wherein at least first and second detectors are connected in series and said first detectors produces a signal at said output means in response to digital information pulses characteristic of both said first and second detectors.

16. The system of claim 14 wherein each of said comparison means includes AND gating means.