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qwitza
Occasional Contributor
Occasional ContributorSDRAM calibration failed.
Hello, after Enpirion stopped selling some of the parts we used on our board, we had to redesign it. We assembled ten boards, and on two of them, I’m now getting an SDRAM calibration error in U-Boot...
qwitzaOccasional Contributor
Occasional Contributorhere, is the file
Archer_AlteraOccasional Contributor
Occasional ContributorHi qwitza
Thanks for uploading the error log.
The function test_load_patterns(0, ALL) returned 170, but the expected value was 255.
This indicates that the test pattern written to DDR (typically 0xFF) was read back as 0xAA (i.e., 170).
Since 0xAA is 0b10101010 and 0xFF is 0b11111111, this suggests that certain DQ bits are stuck at 0. Since only two boards have this issue, it is most likely hardware issue such as DQ pin connectivity issues (open circuit, short circuit, or poor soldering).
Hope this is helpful.
Archer_Altera
