I have a really weird issue with running an SD card on a STM32L496VGT. I can't seem to set any bit in any SDMMC registers. I've tried hard setting a value using my debug tool with the code paused before it gets to the DMA initialization and I cant even do that. I have looked at the disassembly to make sure that actual assembly generated by my test code which is trying to write 3 to the clock divide factor does nothing (images of code attached). Has anyone seen this before or have any ideas what might be going on.