Since #58, it ist possible to dynamically define the SD pins using:
setxxx() methods: setDx, setCK, setCMD, setCKIN, setCDIR or setDxDIR.
init() or begin()
Example of code:
card.setDx(PC8, PC9, PC10, PC11);
while(!card.init(SD_DETECT_PIN)) {
As init() or begin() called the setDx methods with default arguments the first call is simply not applied.