Signaling accommodation

• US 20030151450A1
• Filed: 05/28/2002
• Published: 08/14/2003
• Est. Priority Date: 02/14/2002
• Status: Active Grant

• Current Assignee: Rambus Inc.
• Original Assignee: Rambus Inc.
• Inventors: Nguyen, Huy M., Lau, Benedict C.
• Granted Patent: US 6,876,248 B2
• Time in Patent Office: Days
• US Class Current: 327/540
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C

Abstract

A receiving unit may implement voltage compensation using a parameters table, an analog calibration component, and/or a digital calibration component. In certain implementation(s), an integrated circuit may include a voltage driver that modifies a supplied compensated voltage based on a feedback signal. The feedback signal may be produced responsive to a distributed voltage version of the compensated voltage, to a received data signal, and to a comparison involving an expected data value. In other implementation(s), a parameters table may be initialized by storing calibration values in entries in association with respective multiple identifications of multiple external points. In still other implementation(s), a particular calibration value of multiple calibration values may be ascertained, with the particular calibration value associated with a particular external point; the particular calibration value may be activated; and data from the particular external point may be received using the particular calibration value. Other implementations are also described.

Claims

1. A receiving unit that receives one or more data signals, the one or more data signals having common mode voltages at the receiving unit, the receiving unit comprising:

a voltage driver that supplies a compensated voltage in response to a feedback signal, the compensated voltage being distributed to produce a distributed voltage relative to which at least one of the one or more data signals is evaluated; and

a feedback unit that is responsive to the distributed voltage and to a calibration signal of the one or more data signals to produce the feedback signal;

wherein the feedback unit controls the feedback signal to establish the distributed voltage at a value that is approximately equal to the common mode voltage of the calibration signal of the one or more data signals.

2. The receiving unit as recited in claim 1, wherein the at least one of the one or more data signals is the common mode voltage of the calibration signal of the one or more data signals.

3. The receiving unit as recited in claim 1, wherein the at least one of the one or more data signals is the same data signal as the calibration signal of the one or more data signals.

4. The receiving unit as recited in claim 1, wherein the feedback unit is active and is receiving the calibration signal of the one or more data signals during a calibration phase of the receiving unit.

5. The receiving unit as recited in claim 1, wherein the feedback unit is inactive and is not receiving the calibration signal of the one or more data signals during an operational phase of the receiving unit.

6. The receiving unit as recited in claim 1, wherein the feedback unit is active and is receiving the calibration signal of the one or more data signals during an operational phase of the receiving unit via a dedicated signal receiver and a dedicated bus line.

7. The receiving unit as recited in claim 1, further comprising:

a plurality of signal receivers;

wherein the feedback unit includes at least one signal receiver of the plurality of signal receivers, the at least one signal receiver receiving as input the distributed voltage.

8. The receiving unit as recited in claim 1, wherein the receiving unit comprises an integrated circuit.

9. The receiving unit as recited in claim 1, wherein the receiving unit comprises at least one of a memory system, a printed circuit board, and a computer system.

10. A receiving unit, comprising:

a voltage driver that supplies a compensated voltage, the voltage driver modifying the compensated voltage based on a feedback signal; and

a feedback unit that produces the feedback signal, the feedback unit producing the feedback signal responsive to a comparison involving an expected data value, the feedback unit receiving as input a distributed voltage and a data signal;

wherein a change to the compensated voltage results in a change in the distributed voltage.

11. The receiving unit as recited in claim 10, further comprising:

a data structure having a plurality of entries, each entry of the plurality of entries storing an identification and an associated attribute for a transmitting unit corresponding to the identification.

12. The receiving unit as recited in claim 11, wherein the associated attribute comprises a voltage compensation value;

and wherein the voltage driver is configured to utilize the voltage compensation value when receiving a data signal from the transmitting unit that corresponds to the identification.

13. The receiving unit as recited in claim 12, wherein the voltage driver is further configured to utilize the voltage compensation value when modifying the compensated voltage based on the feedback signal.

14. The receiving unit as recited in claim 10, wherein the feedback unit includes at least one signal receiver and at least one calibration component.

15. The receiving unit as recited in claim 14, wherein the at least one calibration component comprises an analog calibration component, the analog calibration component configured to receive the data signal and determine a common mode voltage of the data signal;

and wherein the at least one signal receiver receives as input the distributed voltage and the common mode voltage of the data signal and produces the feedback signal based on a comparison of the distributed voltage to the common mode voltage of the data signal.

16. The receiving unit as recited in claim 14, wherein the at least one calibration component comprises an analog calibration component, the analog calibration component configured to receive the data signal and determine a common mode voltage of the data signal;

wherein the at least one signal receiver receives as input the distributed voltage and the common mode voltage of the data signal and produces as output the feedback signal, and wherein the feedback signal comprises a binary value indicating which of the distributed voltage and the common mode voltage of the data signal is higher.

17. The receiving unit as recited in claim 14, wherein the at least one calibration component comprises an analog calibration component, the analog calibration component configured to receive the data signal and determine a common mode voltage of the data signal;

wherein the at least one signal receiver receives as input the distributed voltage and the common mode voltage of the data signal and produces as output the feedback signal, and wherein the feedback signal causes the voltage driver to increase the compensated voltage when the distributed voltage is lower than the common mode voltage of the data signal and to decrease the compensated voltage when the distributed voltage is higher than the common mode voltage of the data signal.

18. The receiving unit as recited in claim 14, wherein the at least one signal receiver receives as input the distributed voltage and the data signal and produces an output based on a comparison between the distributed voltage and the data signal;

and wherein the at least one calibration component comprises a digital calibration component, the digital calibration component configured to receive the output of the at least one signal receiver and to produce the feedback signal.

19. The receiving unit as recited in claim 14, wherein the at least one signal receiver receives as input the distributed voltage and the data signal and produces an output based on a comparison between the distributed voltage and the data signal;

and wherein the at least one calibration component comprises a digital calibration component, the digital calibration component configured to receive the output of the at least one signal receiver and to produce the feedback signal responsive to a comparison of the output to the expected data value.

20. The receiving unit as recited in claim 14, wherein the at least one signal receiver receives as input the distributed voltage and the data signal and produces an output based on a comparison between the distributed voltage and the data signal;

wherein the at least one calibration component comprises a digital calibration component, the digital calibration component configured to receive the output of the at least one signal receiver and to produce the feedback signal responsive to a comparison of the output to the expected data value; and

wherein the feedback signal is produced so as to cause the voltage driver to increase the compensated voltage until a high voltage extreme is determined by detecting a data error as a result of the comparison of the output to the expected data value.

21. The receiving unit as recited in claim 14, wherein the at least one signal receiver receives as input the distributed voltage and the data signal and produces an output based on a comparison between the distributed voltage and the data signal;

wherein the at least one calibration component comprises a digital calibration component, the digital calibration component configured to receive the output of the at least one signal receiver and to produce the feedback signal responsive to a comparison of the output to the expected data value; and

wherein the feedback signal is produced so as to cause the voltage driver to decrease the compensated voltage until a low voltage extreme is determined by detecting a data error as a result of the comparison of the output to the expected data value.

22. A system having voltage compensation, comprising:

at least one signal receiver, the at least one signal receiver having a first input receiving a first voltage and a second input receiving a second voltage, the second voltage corresponding to a received data signal; and

a voltage driver, the voltage driver supplying the first voltage to the first input of the at least one signal receiver, the voltage driver configured to change the first voltage supplied to the at least one signal receiver responsive to an output of the at least one signal receiver.

23. The system as recited in claim 22, wherein the first voltage supplied to the first input of the at least one signal receiver is a degraded version of an output voltage of the voltage driver.

24. The system as recited in claim 22, wherein the first voltage supplied to the first input of the at least one signal receiver is changed to be approximately equal to a common mode voltage of the received data signal by the voltage driver.

25. The system as recited in claim 22, wherein the second voltage comprises at least one of (i) a data voltage of the received data signal and (ii) a common mode voltage of the received data signal.

26. An integrated circuit, comprising:

a voltage driver that supplies a compensated voltage, the voltage driver modifying the compensated voltage based on a feedback signal; and

a feedback unit that produces the feedback signal using at least one signal receiver and at least one calibration component, the feedback unit producing the feedback signal responsive to a comparison involving an expected data value, the feedback unit receiving as input a distributed voltage and a data signal;

wherein a modification to the compensated voltage results in a modification of the distributed voltage so that the distributed voltage becomes approximately equal to a common mode voltage of the data signal.

27. The integrated circuit as recited in claim 26, wherein at least a version of the data signal arrives at the integrated circuit from an external transmitting unit;

and wherein the at least one signal receiver receives as a first input the distributed voltage and as a second input at least one of the data signal and a derivative of the data signal that is created by the at least one calibration component.

28. An electronic arrangement, comprising:

a voltage driver means for supplying a compensated voltage, the voltage driver means adapted to modify the compensated voltage based on a feedback signal; and

a feedback means for producing the feedback signal, the feedback means producing the feedback signal responsive to a comparison involving an expected data value, the feedback means receiving as input a distributed voltage and a data signal;

wherein a change to the compensated voltage results in a change in the distributed voltage.

29. The electronic arrangement as recited in claim 28, wherein the feedback means includes analog calibration means for determining a common mode voltage of the data signal;

and wherein the feedback means further includes a signal comparison means that compares the distributed voltage to the common mode voltage of the data signal to produce the feedback signal.

30. The electronic arrangement as recited in claim 28, wherein the feedback means includes a signal comparison means that compares the distributed voltage to the data signal to produce a comparison output;

and wherein the feedback means further includes digital calibration means for comparing the expected data value to the comparison output to produce the feedback signal at least partially responsive thereto.

31. A memory system, comprising:

a plurality of memory storage cells;

a voltage driver that supplies a compensated voltage, the voltage driver modifying the compensated voltage based on a feedback signal;

a plurality of signal receivers, the plurality of signal receivers adapted for receiving a data signal capable of storage within the plurality of memory storage cells, the plurality of signal receivers receiving at least a version of the compensated voltage; and

a feedback unit that produces the feedback signal, the feedback unit including a signal receiver of the plurality of signal receivers, the feedback unit configured to produce the feedback signal using the data signal received via the signal receiver and responsive to a comparison involving an expected data value.

32. The memory system as recited in claim 31, further comprising:

a parameters table, the parameters table including a plurality of entries, each entry of the plurality of entries capable of storing an identification and an associated voltage compensation value, each identification corresponding to a potential transmitting unit;

wherein the voltage driver is configured to utilize the associated voltage compensation value to modify the compensated voltage when the signal receiver of the feedback unit is receiving the data signal from the potential transmitting unit that corresponds to the identification.

33. The memory system as recited in claim 32, wherein the memory system comprises a memory controller;

and wherein the plurality of memory storage cells comprise a buffer.

34. The memory system as recited in claim 31, further comprising:

an identification;

wherein the identification enables a master to access the plurality of memory storage cells.

35. The memory system as recited in claim 34, wherein the memory system comprises a memory storage module;

and wherein the plurality of memory storage cells comprise a memory storage array.

36. The memory system as recited in claim 31, further comprising:

a bus, the bus in communication with the plurality of signal receivers;

wherein the bus is capable of propagating the data signal.

37. A method for providing a compensated voltage when receiving signals, comprising:

supplying a voltage;

receiving a data signal from an external point;

producing a feedback signal responsive to the data signal, the voltage, and an expected data value; and

modifying the voltage being supplied in the action of supplying a voltage based, at least partly, on the feedback signal.

38. The method as recited in claim 37, further comprising:

sending a data value to the external point.

39. The method as recited in claim 38, further comprising:

instructing the external point to return the data value;

wherein the action of receiving occurs after the actions of sending and instructing, and wherein the data signal includes the data value.

40. The method as recited in claim 37, wherein the action of producing comprises the actions of:

determining a common mode voltage of the data signal, the common mode voltage of the data signal potentially reflective of the expected data value; and

comparing the common mode voltage of the data signal to a version of the voltage to produce the feedback signal.

41. The method as recited in claim 37, wherein the action of modifying comprises the actions of:

increasing the voltage if a common mode voltage of the data signal is greater than a version of the voltage; and

decreasing the voltage if a common mode voltage of the data signal is less than a version of the voltage.

42. The method as recited in claim 37, wherein the action of producing comprises the actions of:

comparing the data signal to a version of the voltage to produce a preliminary feedback signal;

comparing the preliminary feedback signal to the expected data value to determine whether or not a data receiving error has occurred; and

producing the feedback signal responsive to determining whether or not a data receiving error has occurred.

43. A method for voltage compensation, comprising:

sampling data at a sampler to produce an average value of the data;

receiving the average value of the data as a first input of a signal receiver;

receiving a distributed voltage as a second input of the signal receiver;

comparing the average value of the data to the distributed voltage at the signal receiver to determine an output therefrom; and

changing the distributed voltage responsive to the output.

44. The method as recited in claim 43, further comprising:

transmitting the data to a destination;

instructing the destination to transmit the data from the destination so that the data can be sampled in the action of sampling data at a sampler.

45. The method as recited in claim 43, wherein the action of sampling data at a sampler comprises at least one of the following actions:

low pass filtering the data at a low pass filter; and

integrating the data at an integrator.

46. The method as recited in claim 43, wherein the data comprises a data pattern having a duty cycle of approximately fifty percent (50%).

47. The method as recited in claim 46, wherein the data pattern is selected from the group comprising 01010101, 00110011, 00010111, 10101010, 11001100, and 10101001.

48. The method as recited in claim 43, wherein the action of changing the distributed voltage responsive to the output comprises:

changing a value of an up/down counter responsive to the output;

applying the value of the up/down counter to establish a gain of a variable gain voltage amplifier; and

amplifying a nominal voltage with the variable gain voltage amplifier to produce a compensated voltage;

wherein a change to the distributed voltage results from the action of amplifying a nominal voltage with the variable gain voltage amplifier to produce a compensated voltage.

49. The method as recited in claim 43, wherein the action of changing the distributed voltage responsive to the output comprises:

changing a value of an up/down counter responsive to the output;

loading a register with the value of the up/down counter;

providing the value from the register to a variable gain voltage amplifier to establish a gain thereof; and

amplifying a nominal voltage with the variable gain voltage amplifier to produce a compensated voltage;

wherein a change to the distributed voltage results from the action of amplifying a nominal voltage with the variable gain voltage amplifier to produce a compensated voltage.

50. A method for voltage compensation, comprising:

sampling data to produce a first voltage;

receiving the first voltage at an input component;

receiving a second voltage at the input component;

comparing the first voltage to the second voltage to produce a feedback signal;

changing a third voltage responsive to the feedback signal;

wherein the second voltage is a degraded version of the third voltage.

51. The method as recited in claim 50, wherein the first voltage comprises a common mode voltage of the data.

52. The method as recited in claim 50, wherein the input component comprises a signal receiver and the action of comparing is performed at the signal receiver.

53. An integrated circuit, comprising:

a voltage driver that supplies a compensated voltage, the voltage driver modifying the compensated voltage based on a feedback signal;

a calibration component receiving a data signal, the calibration component including a sampler, the sampler adapted to receive the data signal and to produce a common mode voltage of the data signal; and

a signal receiver comparing a first input to a second input and outputting the feedback signal, the signal receiver receiving a distributed voltage at the first input and the common mode voltage of the data signal at the second input;

wherein the distributed voltage comprises a degraded version of the compensated voltage.

54. The integrated circuit as recited in claim 53, wherein the sampler comprises at least one of a low-pass filter and an integrator.

55. The integrated circuit as recited in claim 53, wherein the common mode voltage of the data signal comprises an average value of the data signal.

56. The integrated circuit as recited in claim 53, wherein the calibration component comprises at least one switch in series with the sampler, the at least one switch being closed during an initialization phase and open during an operational phase.

57. The integrated circuit as recited in claim 53, wherein the calibration component comprises at least one switch in parallel with the sampler, the at least one switch being open during an initialization phase and closed during an operational phase.

58. The integrated circuit as recited in claim 53, wherein the calibration component comprises a pre-charging component, the pre-charging component adapted to pre-charge the sampler prior to an initialization phase.

59. The integrated circuit as recited in claim 53, wherein the voltage driver has an adjustable gain that changes based on the feedback signal such that the compensated voltage is increased when the distributed voltage is lower than the common mode voltage of the data signal and decreased when the distributed voltage is greater than the common mode voltage of the data signal.

60. The integrated circuit as recited in claim 53, wherein the voltage driver has an adjustable gain that changes as an up/down counter is changed based on the feedback signal;

and wherein the adjustable gain changes such that the compensated voltage is increased when the distributed voltage is lower than the common mode voltage of the data signal and decreased when the distributed voltage is greater than the common mode voltage of the data signal.

61. The integrated circuit as recited in claim 53, wherein the voltage driver has an adjustable gain that changes based on the feedback signal such that the compensated voltage is increased when the distributed voltage is lower than the common mode voltage of the data signal and decreased when the distributed voltage is greater than the common mode voltage of the data signal;

and wherein the adjustable gain is determined by a digital value stored in a register.

62. A system for voltage compensation, comprising:

sampling means for sampling a received data signal to produce an average value of the received data signal;

receiving means for receiving the average value of the received data signal as a first input and a distributed voltage as a second input;

comparing means for comparing the average value of the received data signal to the distributed voltage to determine a comparison output;

voltage means for modifying a compensated voltage responsive to the comparison output; and

degrading means for degrading the compensated voltage to the distributed voltage.

63. A method for voltage compensation, comprising:

receiving data as a first input of a signal receiver;

receiving a distributed voltage as a second input of the signal receiver;

comparing the data to the distributed voltage at the signal receiver to determine at least one result therefrom;

determining whether there is a difference between the at least one result and an expected value;

if there is a difference, noting a current value of a register as an extreme value; and

if there is not a difference, altering the current value of the register; and

changing a compensated voltage responsive to the current value of the register;

wherein a change to the compensated voltage results in a change in the is distributed voltage.

64. The method as recited in claim 63, wherein the at least one result and the expected value each comprise an eight (8)-bit data pattern.

65. The method as recited in claim 63, wherein the action of noting a current value of a register as an extreme value comprises the action of storing the current value of the register into at least one of a high voltage point register and a low voltage point register.

66. The method as recited in claim 63, wherein the action of altering the current value of the register comprises at least one of the following actions incrementing the current value of the register, decrementing the current value of the register, and setting the current value of the register to a new value.

67. The method as recited in claim 63, further comprising:

determining whether a high extreme value and a low extreme value have been noted;

if so,

determining an intermediate value between the high extreme value and the low extreme value; and

setting the current value of the register to equal the intermediate value.

68. The method as recited in claim 67, wherein the action of determining an intermediate value between the high extreme value and the low extreme value comprises at least one of the following actions:

determining an intermediate value using a median value between the high extreme value and the low extreme value; and

determining an intermediate value using a median value between the high extreme value and the low extreme value and an offset therefrom.

69. A receiving unit, comprising:

a voltage driver that supplies a compensated voltage, the voltage driver modifying the compensated voltage based on a feedback signal;

a signal receiver comparing a first input to a second input and outputting a result, the signal receiver receiving a distributed voltage at the first input and a data signal at the second input; and

a calibration component receiving the result and producing the feedback signal;

the calibration component including a comparison unit and calibration data;

the comparison unit configured to receive the result and the calibration data, to compare the result to the calibration data, and to determine whether the result differs from the calibration data;

wherein the distributed voltage comprises a degraded version of the compensated voltage.

70. The receiving unit as recited in claim 69, wherein the feedback signal is formed responsive to the determination by the comparison unit of whether the result differs from the calibration data.

71. The receiving unit as recited in claim 69, wherein the feedback signal is formed responsive to the determination by the comparison unit of whether the result differs from the calibration data such that the voltage driver modifies the compensated voltage when the result does not differ from the calibration data.

72. The receiving unit as recited in claim 69, further comprising:

control logic, the control logic including a high voltage point register and a low voltage point register, the control logic configured to provide the feedback signal such that the voltage driver modifies the compensated voltage when the result does not differ from the calibration data, and wherein the control logic is further configured to store a register value into at least one of the high voltage point register and the low voltage point register when the result does differ from the calibration data.

73. The receiving unit as recited in claim 69, further comprising:

control logic, the control logic including a high voltage point register and a low voltage point register;

the control logic configured to provide the feedback signal such that the voltage driver modifies the compensated voltage when the result does not differ from the calibration data;

wherein the control logic is further configured to store a register value into at least one of the high voltage point register and the low voltage point register when the result does differ from the calibration data; and

wherein the control logic is adapted to determine an intermediate voltage point value based on the high voltage point register and the low voltage point register and to provide the intermediate voltage point value to the voltage driver.

74. The receiving unit as recited in claim 69, wherein the voltage driver includes a storage register that controls a gain of the voltage driver;

and

further comprising;

control logic, the control logic including a high voltage point register and a low voltage point register;

the control logic configured to provide the feedback signal at least indirectly to the storage register such that the voltage driver modifies the compensated voltage when the result does not differ from the calibration data;

wherein the control logic is further configured to store a register value from the storage register of the voltage driver into at least one of the high voltage point register and the low voltage point register when the result does differ from the calibration data; and

wherein the control logic is adapted to determine an intermediate voltage point value based on the high voltage point register and the low voltage point register and to provide the intermediate voltage point value to the storage register of the voltage driver.

75. A method for calibrating reception, comprising:

sending a first data pattern to a first external point;

instructing the first external point to transmit the first data pattern back;

determining a first common mode voltage of a first data signal carrying the first data pattern back;

determining a first calibration value based on the action of determining a first common mode voltage of a first data signal; and

storing the first calibration value in association with a first identification of the first external point.

76. The method as recited in claim 75, wherein the action of sending a first data pattern to a first external point comprises the action of sending the first data pattern to a memory storage module.

77. The method as recited in claim 75, wherein the method is performed by a memory controller.

78. The method as recited in claim 75, wherein the action of determining a first calibration value based on the action of determining a first common mode voltage of a first data signal comprises the action of determining the first calibration value such that the first calibration value may be utilized by a voltage driver to adjust a compensated voltage to improve a voltage margin usable for receiving future data signals from the first external point.

79. The method as recited in claim 75, further comprising:

sending a second data pattern to a second external point;

instructing the second external point to transmit the second data pattern back;

determining a second common mode voltage of a second data signal carrying the second data pattern back;

determining a second calibration value based on the action of determining a second common mode voltage of a second data signal; and

storing the second calibration value in association with a second identification of the second external point.

80. The method as recited in claim 79, wherein the first data pattern is identical to the second data pattern.

81. The method as recited in claim 79, wherein the first data pattern is different from the second data pattern.

82. The method as recited in claim 79, further comprising:

determining a need to request data from the second external point;

ascertaining that the second calibration value is associated with the second external point;

activating the second calibration value;

instructing the second external point to transmit the needed data; and

receiving the needed data from the second external point using the second calibration value.

83. The method as recited in claim 75, wherein the action of determining a first common mode voltage of a first data signal carrying the first data pattern back comprises at least one of the following actions:

determining the first common mode voltage of the first data signal using at least a sampler; and

determining the first common mode voltage of the first data signal using at least a comparison unit, control logic, and a feedback signal.

84. The method as recited in claim 75, wherein the first calibration value comprises a voltage compensation value.

85. The method as recited in claim 75, further comprising:

activating the first calibration value;

instructing the first external point to transmit requested data; and

receiving the requested data from the first external point using the first calibration value.

86. A method for voltage compensation, comprising:

determining a first compensation value based, at least partly, on a first signal received from a first external point;

storing the first compensation value in association with a first identification of the first external point;

determining a second compensation value based, at least partly, on a second signal received from a second external point; and

storing the second compensation value in association with a second identification of the second external point.

87. The method as recited in claim 86, wherein:

the action of storing the first compensation value in association with a first identification of the first external point further comprises the action of storing the first compensation value in a parameters data structure; and

the action of storing the second compensation value in association with a second identification of the second external point further comprises the action of storing the second compensation value in the parameters data structure.

88. The method as recited in claim 86, further comprising:

extracting the second compensation value;

activating the second compensation value; and

receiving data from the second external point using the second compensation value to adjust a voltage.

89. A method for initializing and operating a system having at least receiving functionality, comprising:

executing an initialization, the initialization comprising;

sending at least one data pattern to a plurality of external points;

instructing the plurality of external points to transmit the at least one data pattern back in a respective plurality of signals;

determining a respective plurality of calibration values for the plurality of external points responsive to receipt of the respective plurality of signals; and

storing the respective plurality of calibration values in association with a respective plurality of identifications of the plurality of external points; and

implementing an operational phase, the operational phase comprising;

determining that data is to be received from a particular external point of the plurality of external points;

ascertaining a particular calibration value of the plurality of calibration values, the particular calibration value associated with the particular external point;

activating the particular calibration value; and

receiving the data from the particular external point using the particular calibration value.

90. The method as recited in claim 89, wherein the system comprises a memory system.

91. The method as recited in claim 89, wherein the system comprises a memory controller, and the plurality of external points comprise a plurality of memory storage modules.

92. The method as recited in claim 89, wherein the actions of the implementing an operational phase action are repeated for multiple external points of the plurality of external points.

93. The method as recited in claim 89, wherein the actions of the executing an initialization action are repeated for at least one external point of the plurality of external points.

94. A method for receiving data, comprising:

determining a need to request first data from a first external point;

ascertaining that a first calibration value is associated with the first external point;

activating the first calibration value;

requesting the first external point to transmit the first data; and

receiving the first data from the first external point using the first calibration value.

95. The method as recited in claim 94, further comprising:

determining a need to request second data from a second external point;

ascertaining that a second calibration value is associated with the second external point;

activating the second calibration value;

requesting the second external point to transmit the second data; and

receiving the second data from the second external point using the second calibration value.

96. The method as recited in claim 94, wherein the action of ascertaining that a first calibration value is associated with the first external point comprises the action of accessing a parameters table at an entry having an identification that is associated with the first external point, the entry including the first calibration value.

97. The method as recited in claim 94, wherein the action of activating the first calibration value comprises the action of loading a register with the first calibration value.

98. The method as recited in claim 94, wherein the action of receiving the first data from the first external point using the first calibration value comprises the action of adjusting a voltage that is used to interpret received signaling responsive to the first calibration value.

99. An integrated circuit configured to perform actions comprising:

determining a need to request first data from a first external point;

ascertaining that a first calibration value is associated with the first external point from a parameters data structure;

activating the first calibration value;

requesting the first external point to transmit the first data;

receiving the first data from the first external point using the first calibration value;

determining a need to request second data from a second external point;

ascertaining that a second calibration value is associated with the second external point from the parameters data structure;

activating the second calibration value;

requesting the second external point to transmit the second data; and

receiving the second data from the second external point using the second calibration value.

100. An integrated circuit comprising:

a voltage driver, the voltage driver adapted to modify a voltage output therefrom responsive to a content of a digital register;

a parameters data structure, the parameters data structure including a plurality of entries, each entry of the plurality of entries including an identification and an associated digital value; and

control logic in communication with the voltage driver and the parameters data structure;

the control logic configured to determine that signaling is to be received from an external point, the external point having a particular identification;

the control logic further configured to extract a particular associated digital value that is associated with the particular identification of the external point from the parameters data structure;

the control logic further configured to store the particular associated digital value as the content of the digital register.

101. The integrated circuit as recited in claim 100, wherein the identification comprises at least one of an address and a location on a bus.

102. The integrated circuit as recited in claim 100, wherein the control logic is further configured to determine associated digital values for the plurality of entries by receiving signaling from external points and to store the associated digital values in the parameters data structure.

103. The integrated circuit as recited in claim 100, wherein the control logic is further configured to determine associated digital values for the plurality of entries by receiving signaling from external points and to store the associated digital values in the parameters data structure by at least one of copying and moving the content of the digital register into an entry of the plurality of entries.

104. A receiving unit, comprising:

data structure means for storing a plurality of parameter-related entries, each parameter-related entry of the plurality of parameter-related entries including an identification and at least one associated attribute value;

determining means for determining a need to request data from an external point, the external point having a particular identification;

ascertaining means for ascertaining from the data structure means a particular associated attribute value, the particular associated attribute value included in a particular entry having the particular identification of the external point;

activating the particular associated attribute value;

requesting the external point to transmit the needed data; and

receiving the needed data from the external point using the particular associated attribute value.

105. An integrated circuit, comprising:

a data structure, the data structure including a plurality of entries, each entry of the plurality of entries including an identification and a calibration value, the identification associated with an external point from which signaling may be received, the calibration value being previously determined in a calibration procedure with the external point and being usable to improve voltage margin when receiving signaling from the external point.

106. A memory system, comprising:

a plurality of memory storage modules, each memory storage module including a plurality of memory storage cells and an associated identification;

at least one memory controller, the at least one memory controller including a data structure;

the data structure including a plurality of entries, each entry of the plurality of entries including an associated identification and an associated compensation value;

the associated identification of each entry associated with an associated memory storage module of the plurality of memory storage modules, the associated compensation value of each entry associated with the associated memory storage module;

the at least one memory controller configured to determine each associated compensation value of each entry by receiving signaling from the associated memory storage module.

107. The memory system as recited in claim 106, wherein the at least one memory controller includes a voltage driver that is adapted to use the associated compensation value to improve voltage margin when receiving signaling from the associated memory storage module.