uchar MMC_SPI(data uchar cmd)
{
data uchar i,j=0;
//ACC=0;
for (i = 8; i > 0; i --)
{
j<<=1;
MMC_SCK=0;
j |= MMC_DO;
MMC_DI = (cmd & 0x80)==0x80;
//MMC_DI = cmd >> 7;
MMC_SCK=1;
cmd<<=1;
}
//MMC_SCK=1;
return(j);
}
uchar MMC_SPI(data uchar cmd)
; 15. {
MMC_SPI:
; 16. data uchar i,j=0;
; 17. //ACC=0;
; 18. for (i = 8; i > 0; i --)
MOV $LOCBD MMC_SPI+1,#0
MOV $LOCBD MMC_SPI,#8
MOV $LOCBD MMC_SPI+2,R4
?0001:
MOV A,$LOCBD MMC_SPI
JZ ?0000
?0002:
; 19. {
; 20. j<<=1;
MOV A,$LOCBD MMC_SPI+1
ADD A,ACC
MOV $LOCBD MMC_SPI+1,A
; 21. MMC_SCK=0;
CLR 232.1
; 22. j |= MMC_DO;
CLR A
MOV C,232.0
MOV ACC.0,C
ORL $LOCBD MMC_SPI+1,A
; 23. MMC_DI = (cmd & 0x80)==0x80;
MOV A,$LOCBD MMC_SPI+2
ANL A,#128
XRL A,#128
JZ ?0031
MOV A,#255
?0031:
INC A
MOV C,ACC.0
MOV 232.2,C
; 24. //MMC_DI = cmd >> 7;
; 25. MMC_SCK=1;
SETB 232.1
; 26. cmd<<=1;
MOV A,$LOCBD MMC_SPI+2
ADD A,ACC
MOV $LOCBD MMC_SPI+2,A
DEC $LOCBD MMC_SPI
SJMP ?0001
?0000:
; 27. }
; 28. //MMC_SCK=1;
; 29. return(j);
MOV R4,$LOCBD MMC_SPI+1
; 30. } |
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