Maxim自身出的source code，用uart转IrDA对接收解
你可以看它的控制方式
;*****************************************************************
;IrDA CODE FOR MAX-3100 UART- 8051 based
; Written by: Wettroth 9/13/96- Maxim Integrated Products
;
;MAX-3100 UART demonstration and test code for the 8051 that
;bidirectionally translate IrDA to 232 and 232 to IrDA. Both the
;8051 and IrDA sides run at 9600 baud. All receivers are polled
;to keep code easy to follow. Testing was done with an HP-100
;Palmtop for IrDA and PC running a terminal program. The primary
;purpose of the code is to demonstrate the UART.
;***************************************************************
; CONSTANTS
PCON EQU 87H
;PORT PIN DEFINITIONS- BIT BANGING IF
DOUT BIT P1.0 ;data out (from uart)
DIN BIT P1.1 ;data in (from UART)
SCLK BIT P1.2 ;serial 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 internal 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?
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 on RS-232 side 9600 baud
JMP LOOP ;back to top
;byte recieved from 8051 uart- get it and send out 3100 uart
RCV51: MOV A,SBUF ;data from 8051 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 16 bits from TX1 TX2 and rcv 16 to RX1 RX2
UTLK: CLR CS ;activate cs
MOV A,TX1 ;get high byte
CALL BYT8 ;send out
MOV RX1,A ;get recieved 1
MOV A,TX2 ;get high byte
CALL BYT8 ;send out
MOV RX2,A ;get recieved 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 ;put out 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 8 bits
RET ;done
; end of code
END