I’ve found it difficult to find a 100% complete picture of the SD Card SPI protocool. However, this is what I’ve pieced together and has managed to allow me to communicate with a Sandisk card I had sitting around. Overall progress has been slow as I’ve been occupied with other important things. I have however managed to squash the bug that turned my data line into an oscillator and have successfully read the contents of the OCR register. So, although it’s been slow there has been progress and I expect to be able to pick up the pace again now that things have settled and I’m transitioning back into school.