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问 最近由于串口不够用 需要扩展一个 人家建议用MAX3100来扩展 以前没有接触过  资料上放出来的汇编看了看 貌似有点不通  请高手帮忙做一个C的初始化和传送协议。。。。

放出资料上的汇编
;IrDA CODE FOR MAX-3100 UART-8051 based
;************************************************
;CONSTANTS
;PORT PIN DEFINITIONS-BIN BANGING IF
DOUT BIT p1.0         ;data out (from uart)
DIN BIT p1.1          ;data in (from uart)
SCLK BIT p1.2         ;  clock
CS BIT p1.3           ;chip select-act low
IRQ BIT p3.2          ;(irq)polled in this code
;RAM LOCATIONS
TX1 EQU 10H           ;transmit regs
TX2 EQU 11H
RX1 EQU 12H           ;RECEIVE REGS
RX2 EQU 13H
;***************************************************
        ORG 0H
BEGIN:MOV SP,#70H     ;initialize stack
CLR SCLK              ;clear sclk-normally low
;initialize  8051 interal uart
MOV TMOD,#20H         ;t1 baud
MOV TH1,#253          ;reload value baud 9600/xtal 5.5M
MOV SCON,#50H         ;uart-m1.tx and rx
MOV PCON,#80H         ;double baud rate bit
MOV TCON,40H          ;start baud timer
;initialize max3100 uart-irda mode at 9600 baud
MOV TX1,#0E4H         ;high byte of config-R ints
MOV TX2,#0CAH         ;9600 baud irda mode and two stops
CALL UTLK             ;send to uart - write config
;**********************  MAIN ROUTINE LOOP *********************
LOOP:JNB IRQ,URCV     ;data avail from 3100 uart?        IRQ为0 输出
NRECV:JBC RI,RCV51    ;check for 8051 rcv- tx out irda
JMP LOOP              ;hang here forever
;byte recieved from 3100 uart- get it and send out 8051 uart
URCV:MOV TX1,#0       ;read data
MOV TX2,#0            ;read data
CALL UTLK             ;send to 8051 uart -get data to rx
MOV A,RX2             ;get data to acc
MOV SBUF,A            ;send out rs-232 side 9600 baud
JMP LOOP              ;BACK TO TOP
;byte recieved from 8051 uart- get it and sent 3100uart
RCV51:MOV A,SBUF      ;data from 8-51 uart
      MOV TX1,#80H    ;tx data
      MOV TX2,A       ;data to irda
      CALL UTLK       ;send to uart-send data out IRDA
      JMP LOOP        ;back to top
;**********************************************************
;******SUBROUTINES
;*****UTLK -talk to uart-main routine
;******send 16bits from TX1 TX2 and rov 16 to RX1 RX2
UTLK:CLR CS           ;activate cs
     MOV A,TX1        ;get high byte
     CALL BYT8        ;SEND OUT
     MOV RX2,A        ;get recevied 2
     SETB CS          ;set cs high
     RET              ;DONE
;*********************************
;**BYT8- SHIFT OUT &IN 8 BITS WITH SPI CLOCKING -FROM AND TO ACC
BYT8:MOV R4,#8        ;8 bits to send
SETB DIN              ;make sure din is input
B8LP: RLC A           ;get msb of acc to carry
      MOV DOUT,C      ;OUT OU T ON PIN
      SETB SCLK       ;CLOCK HIGH-CLOCK
    MOV C,DIN         ;get data after clk high
    CLR SCLK          ;clock low
    MOV ACC.0,C       ;put in lsbit of a
      DJNZ  R4,B8LP   ;loop til 8bits
      RET             ;done
;*****end of

  END

不知道他开串口干什么。。。貌似没有用到串口啊。。。希望有高手指点我
拜师~~~~ 答 1: 希望有用过的达人路过  顺便贴下程序短短的  没多少。。。希望帮忙啦