ch18_将外部存储器（16位）值转化成6个bcd码.asm

51单片机基础篇 对于有一定基础的人看看 包含书中所以的源代码

     ;FUNCTION NAME: HEX_TO_BCD
     ;FUNCTION: CONVERT 2 BYTE HEX TO 6 BYTE BCD CODE
     ;HEX DATA   IN(DPTR+1)(DPTR)
     ;BCD RESULT IN (09H)(08H)(07H)(06H)
     ;
     HEX_TO_BCD
           	MOV  	R0,#04H
           	MOVX 	A,@DPTR
           	MOV  	@R0,A
           	INC  	R0
           	INC   	DPTR
           	MOVX  	A,@DPTR
           	MOV  	@R0,A
           	INC   	R0
           	LCALL	CLEAR_INTERNAL_DATA_MEMORY+2 	;CLEAR(06)(07)(08)(09)
           	MOV   	09H,#16  		        ;COUNT
     $1    	MOV   	R0,#04H       	                ;HEX DATA
           	MOV   	R2,#02H
           	CLR  	C
     $2   	MOV   	A,@R0     		        ;SHIFT LEFT 1 BIT WITH CARRY
           	RLC  	A
           	MOV  	@R0,A
           	INC   	R0
           	DJNZ 	R2,$2
           	MOV   	R2,#03H
     $3    	MOV   	A,@R0      		        ;A=(06H)
           	ADDC  	A,A   			        ;A=A+CARRY
           	DA     	A      			        ;DECIMAL  ADJUST
           	MOV  	@R0,A
           	INC   	R0
           	DJNZ 	R2,$3
           	DJNZ 	09H,$1
     RET