;小直流电机调速程序 ORG 05E0H SE13: MOV SP,#53H MOV 7EH,#00H MOV 7DH,#08H MOV 7CH,#03H
MOV 7BH,#02H ;显示缓冲区初值 LO20: MOV A,#80H ;停止 CALL LO21
MOV A,#00H ;反转 CALL LO21
MOV A,#80H ;停止 CALL LO21
MOV A,#0FFH ;正转 CALL LO21 SJMP LO20
;====D/A直流电机正转、反转、停止=== LO21: MOV DPTR,#0FFE0H
MOVX @DPTR,A ;送0832转换 MOV R0,#79H LCALL PTDS MOV R2,#00H
L023: LCALL DIS ;显示 DJNZ R2,L023 RET ;---------------------------
PTDS: MOV R1,A ;拆送显示缓冲区 ACALL PTDS1 MOV A,R1 SWAP A PTDS1: ANL A,#0FH MOV @R0,A INC R0 RET
;----------------------------- DIS: PUSH DPH PUSH DPL SETB RS1
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MOV R0,#7EH MOV R2,#20H MOV R3,#00H MOV DPTR,#LS0 LS2: MOV A,@R0 MOVC A,@A+DPTR MOV R1,#0DCH MOVX @R1,A MOV A,R2 inc R1 MOVX @R1,A LS1: DJNZ R3,LS1 CLR C RRC A MOV R2,A DEC R0 JNZ LS2 movx @r0,a
dec r0 cpl a movx @r0,a
CLR RS1 POP DPL POP DPH RET ;----------------------------
LS0: DB 0C0H,0F9H,0A4H,0B0H,99H,92H DB 82H,0F8H,80H,90H,88H,83H,0C6H DB 0A1H,86H,8EH,0FFH,0CH,89H,7FH,0BFH ;-------------------------------
END
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