Multi-bit deskewing of bus signals using a training pattern
View Patent ↗A method for multi-bit de-skewing of parallel bus signals is disclosed. The method includes receiving data comprising a multi-bit word and a training pattern. After a first control word of the training pattern is detected, the number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of a parallel bus is calculated. The number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of the parallel bus is transmitted to a bit delay line. The system then outputs a de-skewed data word.
1. A method for de-skewing of parallel bus signals comprising:
receiving data comprising a multi-bit word and a training pattern;
detecting a first control word of the training pattern;
calculating a number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of a parallel bus;
transmitting the number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of the parallel bus to a bit delay line; and
outputting a de-skewed data word.
2. The method of claim 1 , wherein said de-skewing involves single bit de-skewing.
3. The method of claim 2 , wherein said de-skewing involves multiple bit de-skewing.
4. The method of claim 1 , wherein a position of a training control word that is detected provides a reference from which skew is established and a position of a training data word that is detected provides a reference from which a per bit calculation of a delay skew of data bits in a parallel bus is made.
5. The method of claim 4 , wherein the per bit calculation of delay skew is made by calculating the number of bits from a detected training data word position to a signal transition occurring prior to detection of the training data word.
6. The method of claim 5 , wherein a final delay skew per bit is verified by comparing the skew measured after a first detected data training word position with that measured after a last detected training data word position.
7. The method of claim 1 , further comprising:
receiving the multi-bit data word and training pattern into a delay buffer; and
recording a contents of the delay buffer upon the detection of a first control word of the training pattern.
8. A computer useable medium having computer useable code embodied therein causing a computer to perform operations comprising:
receiving data comprising a multi-bit word and a training pattern;
detecting a first control word of the training pattern;
calculating a number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of the parallel bus;
transmitting the number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of the parallel bus to a bit delay line; and
outputting a de-skewed data word.
9. The computer useable medium of claim 8 , wherein said de-skewing involves single bit de-skewing.
10. The computer useable medium of claim 9 , wherein said de-skewing involves multiple bit de-skewing.
11. The computer useable medium of claim 10 , wherein a position of a training control word that is detected provides a reference from which skew is established and a position of a training data word that is detected provides a reference from which a per bit calculation of a delay skew of data bits in a parallel bus is made.
12. The computer useable medium of claim 11 , wherein the per bit calculation of delay skew is made by calculating the number of bits from a detected training data word position to a signal transition occurring prior to detection of the training data word.
13. The computer useable medium of claim 12 , wherein a final delay skew per bit is verified by comparing the skew measured after a first detected data training word position with that measured after a last detected training word position.
14. The computer useable medium of claim 8 , further comprising:
receiving the multi-bit data word and training pattern into a delay buffer; and
recording a contents of the delay buffer upon the detection of a first control word of the training pattern.
15. A computer controlled de-skewing system comprising:
a bus;
a computer readable memory units connected to said bus;
a processor coupled to said bus said processor for executing a method for implementing an application comprising:
receiving data comprising a multi-bit word and a training pattern;
detecting a first control word of the training pattern;
calculating a number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of the parallel bus;
transmitting the number of bits needed to de-skew each data bit of a multi-bit data word in each bit-line of the parallel bus to a bit delay line; and
outputting a de-skewed data word.
16. The computer controlled de-skewing system of claim 15 , wherein said de-skewing involves single bit de-skewing and multiple bit de-skewing.
17. The computer controlled de-skewing system of claim 16 , wherein a position of a training control word that is detected provides a reference from which skew is established and the position of a training data word that is detected provides a reference from which a per bit calculation of the delay skew of data bits in a parallel bus is made.
18. The computer controlled de-skewing system of claim 17 , wherein the per bit calculation of delay skew is made by calculating the number of bits from a detected training data word position to a signal transition occurring prior to detection of the training data word.
19. The computer controlled de-skewing system of claim 18 , wherein a final delay skew per bit is verified by comparing the skew measured after a first detected data training word position with that measured after a last detected training word position.
20. The computer controlled de-skewing system of claim 19 , further comprising:
receiving the multi-bit data word and training pattern into a delay buffer; and
recording a contents of the delay buffer upon the detection of a first control word of the training pattern.