Hello *,
I'm currently trying to use a micro-sd card breakout board on my Nucleo-H743ZI to store some data using the SDMMC interface and the FatFS middleware v0.12c (The breakout board is just here for the pull-up resistors on the lines).
I've setup the SDMMC1 interface without any IT or DMA, and a clock running at 25 MHz from a PLL divider.
So my problem is that, during the Init phase (1-bit SD mode running at 400KHz max) the "basic" commands that receive a response on the CMD line are fine, but as soon as I run an ACMD (CMD55 followed by CMD13 is my first problem), the R1 response is read, but then the data that is supposed to be read is never read in the FIFO, thus blocking the polling loop.
I've seen on the scope that the command, R1 response and D0 line have content on them and that the CLK line is less than 400KHz (but close enough).
I've checked the DPSM with a breakpoint just after the ACMD13 is sent, and the registers indicate that the state machine is not in Idle, so I guess it should be in Wait_R mode (that I don't know how to verify). The DCTRL register also indicates DTEN=1, DTDIR=1, BOOTACKEN=0, which are the conditions for the DPSM to go to Wait_R.
Also the DTIMER register never counts down as it should be doing according to the documentation.
I'm currently out of ideas to find the issue, if anyone could help me troubleshoot, it would be awesome.
** EDIT **
Actually, to be a bit more precise, I see in the registers after the ACMD13 is sent that the block size is correct (64 bytes for the 512 bits that ACMD13 returns) and the data length is also 64 bytes, but this data length never decreases as well.
** EDIT **
After the week-end I got back to this issue and realized that on my Nucleo-H743ZI2 there were missing solder bridges in order to use the pins from the sides (the holes where you can solder).
So everything is solved !
