A51 MACRO ASSEMBLER  EX8_5A                                                               11/27/2009 22:21:38 PAGE     1


MACRO ASSEMBLER A51 V8.01
OBJECT MODULE PLACED IN ex8-5a.OBJ
ASSEMBLER INVOKED BY: C:\Keil\C51\BIN\A51.EXE ex8-5a.asm SET(SMALL) DEBUG EP

LOC  OBJ            LINE     SOURCE

                       1     ;$include (STC12C5A.INC) ;包含STC12C5A60S2單片機寄存器定義文件
                +1     2     $nomod51 
                +1     3  +1 $save 
                +1   152  +1 $restore 
  0020               153     BITTEST DATA    20H
  0001               154     S2TIbit BIT             01H
  0000               155     S2RIbit BIT             00H
0000                 156     ORG             0000H
0000 020100          157                     LJMP    MAIN
0043                 158                     ORG             0043H
0043 020113          159                     LJMP    UART2_ISR
0100                 160                     ORG             0100H
0100 758160          161     MAIN:   MOV             SP,#60H                 ;設置堆棧
0103 759A50          162                     MOV             S2CON,#50H              ;01010000 8位可變波特率，無奇偶校驗
                             位,允許接收
0106 759CFD          163                     MOV             BRT,#0FDH
0109 758E11          164                     MOV             AUXR,#11H       ;BRTR = 1(啟動BRT), S1BRS = 1
010C 75AF01          165                     MOV    IE2, #01H        ;允許串口2中斷,ES2=1
010F D2AF            166                     SETB    EA
0111 80FE            167                     SJMP    $
0113                 168     UART2_ISR:
0113 859A20          169                     MOV     BITTEST,S2CON   ;將S2CON保存到20H單元以便位尋址
0116 100005          170             JBC     S2RIbit,RDATA   ;若是接收中斷，則將S2RI清零
0119 C201            171                     CLR             S2TIbit                 ;否則就是發送中斷，將S2TI清零
011B 020123          172                     LJMP    RETURN
011E E59B            173     RDATA:  MOV             A,S2BUF         ;讀取收到的示