I2C

; TXD P1.0 = CLOCK
; RXD P1.1 = DATA

$NOMOD51			;   importes
#include "reg932.h"		;   for
				;   at
prog	SEGMENT CODE		;   undgå
	RSEG	prog		;   fejl
				;
?C_START:			;
	public ?C_START	       	;

	jmp 	80H	;
	org	80H	; hvad gør disse "!!!!"

 	mov	divm,#9		;(120KHz)
	mov	p1m1,#0		;
	mov	p1m2,#0		; sætter portene op
;	mov	p1,#0H		;
;	mov 	scon, #0 	; SKAL BRUGES DA DER ARBEJDES MED MODE-0

	call i2cinit

//******************************
	call startc
	mov  a,#10010000b
	call send
	call ack
	mov  a,#10101100b
	call send
	call ack
	mov  a,#00000000b
	call send
	call ack
	call stop
//******************************

	call DEELAY

//******************************
	call startc
	mov  a,#10010000b
	call send
	call ack
	mov  a,#10100001b
	call send
	call ack
	mov  a,#00111001b
	call send
	call ack
	mov  a,#00000000b
	call send
	call ack
	call stop
//******************************

	call DEELAY

//******************************
	call startc
	mov  a,#10010000b
	call send
	call ack
	mov  a,#10100010b
	call send
	call ack
	mov  a,#00001010b
	call send
	call ack
	mov  a,#00000000b
	call send
	call ack
	call stop
//******************************

	 call DEELAY

//******************************
	call startc
	mov  a,#10010000b
	call send
	call ack
	mov  a,#10101010b
	call send
	call ack
	call stop
//******************************
	jmp $






;***************************************
;Ports Used for I2C Communication
;***************************************
        PDA equ P1.0
        PCL equ P1.1


;***************************************
;Initializing I2C Bus Communication
;***************************************
i2cinit:
        setb PDA
        setb PCL
        ret

;****************************************
;ReStart Condition for I2C Communication
;****************************************
rstart:
        clr PCL
        setb PDA
	setb PCL
        clr PDA
        ret

;****************************************
;Start Condition for I2C Communication
;****************************************
startc:
        setb PCL
        clr PDA
        clr PCL
        ret

;*****************************************
;Stop Condition For I2C Bus
;*****************************************
stop:
        clr PCL
        clr PDA
        setb PCL
        setb PDA
        ret

;*****************************************
;Sending Data to slave on I2C bus
;*****************************************
send:
        mov r7,#08
back:
        clr PCL
        rlc a
        mov PDA,c
        setb PCL
        djnz r7,back
        clr PCL
        setb PDA
        ret

;*****************************************
;ACK and NAK for I2C Bus
;*****************************************
ack:
        clr PDA
        setb PCL
	nop
	nop
        clr PCL
        setb PDA
        ret

nak:
        setb PDA
        setb PCL
        clr PCL
        setb PCL
        ret

;*****************************************
;Receiving Data from slave on I2C bus
;*****************************************
recv:
        mov r7,#08
back2:
        clr PCL
        setb PCL
        mov c,PDA
        rlc A
        djnz r7,back2
        clr PCL
	nop
	nop
        ;setb PDA
        ret

DEELAY:
      	mov r4,#50

DELL:
	djnz r3,DELL
	djnz r4,DELL
	ret




	end