Version 1.2 of the MIPI D-PHY specification states that the TSKEWCAL minimum value is 210 UI (1024 UI).
Is it possible to set the length of the periodic deskew pattern (TxSkewCalHS pulse length) to 1024 UI or 128 txbyteclockhs in the MIPI D-PHY TX IP?
The MIPI D-PHY TX IP can send a minimum length of 1024 UI or 128 txbyteclockhs for the periodic deskew-pattern.
Please note that the length of the periodic deskew pattern sent by the transmitter should match the requirement of the receiver side.
For example, if the user wants to do a MIPI D-PHY TX IP to MIPI D-PHY RX IP loopback test, the periodic deskew-pattern setting should be set to meet the MIPI D-PHY RX IP minimum requirement.
The MIPI D-PHY RX deskew algorithm requires a minimum of 8192 UI (or 1024 rxbyteclockhs) of periodic deskew-pattern to do calibration correctly.
Failure to meet the minimum requirement of 8192 UI for the periodic deskew-pattern can cause CRC errors to appear on the received HS long-packet.
Notes:
Periodic Deskew-Pattern Length [UI] | Max physical skew which can be accurately removed during periodic calibration. |
2^13 | 800ps |
2^14 | 1376ps |
2^15 | 1376ps |
Answer Number | Answer Title | Version Found | Version Resolved |
---|---|---|---|
54550 | LogiCORE IP MIPI D-PHY - Release Notes and Known Issues for the Vivado 2015.3 tool and later versions | N/A | N/A |