Hello all,
AM1808, WinCE 6.0 BSP from MPC Data
In our application we use a 64GB SD card for our data storage. exFAT if selected in the catalog. Everything has worked fine for us until we got our latest batch of SD cards from SanDisk. WinCE can store data on the card, we then retrieve and delete that data on a PC and then it quits working in our WinCE unit. It continues to work in the PC. This batch of SD cards has a higher transfer speed spec'ed than what appeared on the previous batches. Here is what I have observed:
SanDisk Ultra 64GB Class 10, 30MB/s -- Works well
SanDisk Ultra 64GB Class 10, 40MB/s -- Works only once
SanDisk Extreme Pro 32GB Class 10, 95MB/s -- Works only once
It appears that as the speeds have increased, there is a point at which the SD card driver no longer configures the port correctly. There is some possibility that my PCB layout is contributing to the problem. If slower cards are being phased out, our system will no longer work. Please advise on how to fix this.
Best Regards,
Nelson