FDS CRC errors

[nrbrook]

We have a firmware using FDS with #define FDS_CRC_CHECK_ON_READ 1 and #define FDS_CRC_CHECK_ON_WRITE 1.

In my testing it works fine, but for another engineer in a different location they are seeing a lot of CRC errors (0x860C) with multiple devices, and eventually the flash seems to get full. What can cause CRC errors? I suspected low voltage supply, but we haven't confirmed or rejected that theory yet.

[nrbrook]

My colleague shipped a problem unit to me, and I was able to reproduce the issue. The issue can be reproduced even after a complete erase and reprogram. So the problem is hardware bound. This presumably narrows the cause down to

• A faulty batch of Nordic modules
• A PCB manufacturing defect
• Something that happened after manufacture that damaged it.

Can you suggest anything we can try? Would it be possible to send Nordic a unit for further analysis?