1.6. Test Result Comments
In each test case, the JESD204B receiver IP core successfully initialize from CGS phase, ILA phase, and until user data phase.
No data integrity issue is observed by the PRBS and Ramp checker for all JESD configurations.
In the deterministic latency measurement, consistent total latency is observed across multiple power cycles and resets.
For a few JESD configurations, to avoid lane deskew error or achieve deterministic latency on FPGA, RBD offset/LMFC offset register needs to be programmed. The modes and the corresponding values used are tabled below.
Mode (LMF) | SCR | csr_rbd_offset (syncn_sysref_ctrl [10:3]) | csr_lmfc_offset (syncn_sysref_ctrl [19:12]) |
---|---|---|---|
112 – K16 | 0/1 | N/A | 4 |
211 – K32 | 0/1 | 0x7 | N/A |
211 – K20 | 0/1 | 0x3 | 0x15 |
211 – K16 | 0/1 | 0x7 | N/A |
411 – K20 | 0/1 | N/A | 0x2 |
811 – K32 | 0/1 | 0x5 | N/A |
811 – K20 | 1 | 0x2 | 0x2 |
812 – K32 | 0/1 | 0xD | N/A |
812 – K16 | 0/1 | 0x5 | N/A |
222 – K16 | 0/1 | N/A | 0x4 |
421 – K20 | 0/1 | 0x4 | N/A |
821 – K20 | 0/1 | N/A | 0x2 |
148 – K32 | 0/1 | 0x3F | N/A |
148 – K16 | 0/1 | 0x1F | N/A |
244 – K16 | 0/1 | 0xF | N/A |
841 – K20 | 0/1 | N/A | 0x1 |
288 – K16 | 0/1 | 0x1F | N/A |
5 The JESD mode gives consistent latency even without LMFC offset, but the LMFC offset is still used to reduce the latency value.