( Initiate SPI exchange with the SD card. n is the data to
send. )
CODE _sdcSR ( n -- n )
HL POPqq,
chkPS,
A L LDrr,
SDC_SPI OUTnA,
NOP, NOP,
SDC_SPI INAn,
L A LDrr,
HL PUSHqq,
;CODE