write_1820.s

嵌入式linux系统是如今比较热门的一个方向

WRITE_1820:
MOV R2,#8 			;一共8位数据
CLR C 
WR1:
CLR WDDATA
MOV R3,#6
DJNZ R3,$
RRC A
MOV WDDATA,C
MOV R3,#24
DJNZ R3,$
SETB WDDATA
NOP
DJNZ R2,WR1
SETB WDDATA
RET