AnsweredAssumed Answered

Problem with ESDHC on K70

Question asked by Chris Solomon on Sep 1, 2014
Latest reply on Sep 10, 2014 by Rick Tseng


I am trying to get the ESDHC driver in MQX going on my K70 based product.


I know the out of the box MQX doesn't support eMMC, but we have been using a Samsung 4GB eMMC device under MQX 4.0.1 - we were able to use this device with modification to the initialization sequence in sdcard_esdhc.


I'm not sure the device is relevant to our issue because we aren't able to get that far with MQX

The basic initialization starts with car identification, which begins with CMD0 (which fails with CTOE and CCE), but succeeds on the second attempt, then the second command is a CMD8, which always fails with CTOE and CC.

Since the basic card identification should work with any device type it seems that there is a more fundamental problem.


I have done side-by-side debugging with GDB and confirmed that the port pins registers are configure as they were previously, that the system clock setup is the same (96MHz generated by PLL0 using OSC0), and aside from expected differences due to the use of interrupts and DMA the ESDHC registers look the same, but it still doesn't want to play ball.


Any suggestions?