AN 712: Altera JESD204B MegaCore Function and ADI AD9625 Hardware Checkout Report

ID 683294
Date 6/13/2016
Public

1.7. Test Result Comments

In each test case, the RX JESD204B IP core successfully initialize from CGS phase, ILA phase, and until user data phase. Except for LMF=611 test cases, no data integrity issue is observed by the ramp checker and PRBS checker. For LMF=611 test cases, no data integrity check is performed because Altera transport layer does not support N'=12 configuration.

In deterministic measurement test case DL.3, the link clock count in the FPGA depends on board layout and the LMFC offset value set in the ADC register. The link clock count varies by only one link clock when the FPGA and ADC are reset or power cycled. The link clock variation in the deterministic latency measurement is caused by word alignment, where control characters fall into the next cycle of data some time after realignment. This makes the duration of ILAS phase longer by one link clock some time after reset or power cycle. For LMF=214 and LMF=118 test cases, the LMFC or RBD offset value is tuned at the FPGA IP core instead of at the ADC for consistent latency.