Forum Discussion
Hi Adzim,
Thank you for sending the updated parameters. I have applied the suggested settings and retested with similar results (i.e. EMIF example design passes local calibration with similar margins and HPS fails to calibrate and/or hangs on U-Boot SPL).
I did have some additional questions:
1. We are currently testing with a memory clock of 400MHz (DDR3-800) with the thought that slowing down the memory interface would give us the best chance of successful calibration. Is this a good idea, or should we run at the rated DDR3-1600 speed of the SODIMM?
2. Are the settings you provided taking into account our memory clock of 400MHz, or should we make additional adjustments (such as dropping our CAS latency to 6 and write CAS latency to 5)?
3. For tRRD, tWTR, and tRTP, you changed the values from 4 cycles to 3. Is this correct per pg. 81 of the memory datasheet? Also, would you set tFAW to 50ns for DDR3-800 or 40ns for DDR3-1600 since we're using x16 devices?
4. Since the EMIF example design passes calibration, are there things specific to the GHRD that we should be looking at (e.g. reset, PLL lock status, any debug registers, etc) to let us know the status of the calibration?
Thanks,
Greg
- gschuell2 years ago
New Contributor
Hi Adzim,
I also got some skew information from the board designer and have attached it here. Did not notice a major difference in the results when applied.
Thanks,
Greg