MCS-51定时器，串行口和中断初始化程序

　　程序框图

　　电路

程序

0030758160 CHK00:MOVSP,#60H

00331204A5 LCALLLEDP

0036900081 MOVDPTR,#CLOCK

0039A882 MOVR0,DPL

003BA983 MOVR1,DPH

003D90000B MOVDPTR,#000BH

00407402 MOVA,#02H

0042F0 MOVX@DPTR,A

0043A3 INCDPTR

0044E9 MOVA,R1

0045F0 MOVX@DPTR,A

0046A3 INCDPTR

0047E8 MOVA,R0

0048F0 MOVX@DPTR,A

0049120DF0 CHK0:LCALL LCK0 ;键扫，显示子程序

004C120068 LCALL PTDS0 ;显示缓冲区放数子程序

004F758901 MOVTMOD,#01H

005243A882 ORLIE,#82H

0055758AB7 MOVTL0,#0B7H

0058758C3C MOVTH0,#3CH;定时中断初始化

005B752300 MOV23H,#00H

005ED28C SETBTR0 ;开定时

0060120425 LOO5:LCALL DIS ;显示

0063120068 LCALL PTDS0

006680F8 SJMPLOO5

00687879 PTDS0:MOVR0,#79H

006AE522 MOVA,22H

006C1177 ACALL PTDS

006EE521 MOVA,21H

00701177 ACALL PTDS

0072E520 MOVA,20H

00741177 ACALL PTDS

007622 RET

0077F9 PTDS:MOVR1,A ;拆送显示缓冲区

0078117C ACALL PTDS1

007AE9 MOVA,R1

007BC4 SWAPA

007C540F PTDS1:ANLA,#0FH

007EF6 MOV@R0,A

007F08 INCR0

008022 RET

0081758AB7 CLOCK:MOVTL0,#0B7H

0084758C3C MOVTH0,#3CH ;恢复初值

0087C0D0 PUSHPSW

0089C0E0 PUSHACC

008BD2D3 SETB0D3H ;保护

008D0523 INC23H ;0.1秒加1

008FE523 MOVA,23H

0091B40A27 CJNEA,#0AH,DONE ;1秒到吗？

0094752300 MOV23H,#00H ;清0.1秒单元

0097E522 MOVA,22H

0099 04 INC A ;秒加1