'****************************************************************
'*  Name    : UNTITLED.BAS                                      *
'*  Author  : Timothy Box                                       *
'*  Notice  : Copyright (c) 2005 TJB Systems Ltd                *
'*          : All Rights Reserved                               *
'*  Date    : 19/03/2005                                        *
'*  Version : 1.0                                               *
'*  Notes   :                                                   *
'*          :                                                   *
'****************************************************************



#Disable BUSIN
#DISABLE BUSOUT
DIM BPF AS BYTE SYSTEM
DIM GPR AS BYTE SYSTEM
DIM PP1 AS BYTE SYSTEM
DIM PP1H AS BYTE SYSTEM
DIM PP3 AS BYTE SYSTEM
DIM PP4 AS BYTE SYSTEM

DIM i2c_control AS BYTE SYSTEM
CLEAR i2c_control
GOTO OVER_CODE
I2C_PINSET1 MACRO
    num_byte 1, i2c_control
    ENDM
I2C_PINSET2 MACRO
    num_byte 2, i2c_control 
    ENDM            
I2C_PINSET3 MACRO
    num_byte 4, i2c_control 
    ENDM
ASM
busin2 BSF BPF,4
	BTFSS BPF,4
BUSIN BCF BPF,4
	BTFSC BPF,5
	GOTO $ + 5
	BSF BPF,5
	CALL i2c@start
	SKPNC
	GOTO bus@stp
	BCF BPF,2
bus@ina MOVLW 8
	MOVWF PP1H
	CALL b@gb
	RLF PP1,f
	DECFSZ PP1H,f
	GOTO $ - 3
	BTFSC BPF,2
	GOTO $ + 8
	BTFSC BPF,4
	GOTO $ + 2
bus@ack CALL b@dal
	CALL b@ckh
	CALL b@ckl
	BTFSC BPF,4
	CALL bus@stp
	CALL b@dah
	CLRC
	MOVFW PP1
	GOTO i2c@fin
busout2 BSF BPF,4
	BTFSS BPF,4
BUSOUT BCF BPF,4
	BTFSC BPF,6
	GOTO $ + 6
	ANDLW 254
	MOVWF GPR
	BSF BPF,6
	CLRC
	GOTO i2c@fin
	BTFSC BPF,7
	GOTO $ + 7
	MOVWF PP3
	BSF BPF,7
	CALL i2c@start
	SKPNC
	GOTO bus@stp
	MOVFW PP3
	CALL b@wrtc
	SKPNC
	GOTO bus@stp
	BTFSS BPF,4
	GOTO i2c@fin
bus@stp CALL b@dal
	CALL b@ckh
	BCF BPF,6
	BCF BPF,7
	BCF BPF,5
	BCF BPF,2
	CALL b@dah
i2c@fin
	BSF PP4,0
	SKPC
	BCF PP4,0
	GOTO i@nt
i2c@start
	CALL bus@strt
	MOVFW GPR
	BTFSC BPF,5
	IORLW 1
b@wrtc MOVWF PP1
	MOVLW 8
	MOVWF PP1H
	RLF PP1,f
	CALL b@dah
	SKPNC
	GOTO $ + 2
	CALL b@dal
	CALL b@ckh
	CALL b@ckl
	DECFSZ PP1H,f
	GOTO $ - 8
	CALL b@dah
b@gb CALL b@ckh
	GOTO $ + 1
	CLRWDT
	CLRC
	#IFDEF SDA_PORT2
	   BTFSC i2c_control,1
	   GOTO b@sp2
	#ENDIF
	#IFDEF SDA_PORT3
	   BTFSC i2c_control,2
	   GOTO b@sp3
    #ENDIF	
b@sp1	
	BTFSC SDA_PORT1,SDA_PIN1
	SETC
	GOTO b@spend		
b@sp2
    #IFDEF SDA_PORT2	
	   BTFSC SDA_PORT2,SDA_PIN2
	   SETC
	   GOTO b@spend
    #ENDIF		
b@sp3
    #IFDEF SDA_PORT3	
	   BTFSC SDA_PORT3,SDA_PIN3
	   SETC
    #ENDIF
b@spend	
	CALL b@ckl
	RETURN
bus@strt
	CALL b@dah
	CALL b@ckh
	CALL b@dal
b@ckl
	#IFDEF SDA_PORT2
	   BTFSC i2c_control,1
	   GOTO b@ckl2
	#ENDIF
	#IFDEF SDA_PORT3
	   BTFSC i2c_control,2
	   GOTO b@ckl3
    #ENDIF
	BCF SCL_PORT1,SCL_PIN1
	BSF 3,5
	BCF SCL_PORT1,SCL_PIN1
	GOTO b@rst
b@ckl2
    #IFDEF SDA_PORT2
	   BCF SCL_PORT2,SCL_PIN2
	   BSF 3,5
	   BCF SCL_PORT2,SCL_PIN2
	   GOTO b@rst
    #ENDIF
b@ckl3    
    #IFDEF SDA_PORT3
	   BCF SCL_PORT3,SCL_PIN3
	   BSF 3,5
	   BCF SCL_PORT3,SCL_PIN3
	   GOTO b@rst
    #ENDIF    	
b@ckh
	#IFDEF SDA_PORT2
	   BTFSC i2c_control,1
	   GOTO b@ckh2
	#ENDIF
	#IFDEF SDA_PORT3
	   BTFSC i2c_control,2
	   GOTO b@ckh3
    #ENDIF 
    BSF 3,5         
    BSF SCL_PORT1,SCL_PIN1
    GOTO b@rst
b@ckh2
    #IFDEF SDA_PORT2
       BSF 3,5 
	   BSF SCL_PORT2,SCL_PIN2
	   GOTO b@rst
    #ENDIF
b@ckh3
    #IFDEF SDA_PORT3
       BSF 3,5
	   BSF SCL_PORT3,SCL_PIN3
	   GOTO b@rst
    #ENDIF     
b@dah
	#IFDEF SDA_PORT2
	   BTFSC i2c_control,1
	   GOTO b@dah2
	#ENDIF
	#IFDEF SDA_PORT3
	   BTFSC i2c_control,2
	   GOTO b@dah3
    #ENDIF 
    BSF 3,5   
    BSF SDA_PORT1,SDA_PIN1
	GOTO b@rst
b@dah2	
    #IFDEF SDA_PORT2
       BSF 3,5	
	   BSF SDA_PORT2,SDA_PIN2
	   GOTO b@rst	
	#ENDIF
b@dah3	
    #IFDEF SDA_PORT3
       BSF 3,5	
	   BSF SDA_PORT3,SDA_PIN3
	   GOTO b@rst	
	#ENDIF	
b@dal 
	#IFDEF SDA_PORT2
	   BTFSC i2c_control,1
	   GOTO b@dal2
	#ENDIF
	#IFDEF SDA_PORT3
	   BTFSC i2c_control,2
	   GOTO b@dal3
    #ENDIF    
    BCF SDA_PORT1,SDA_PIN1
	BSF 3,5
	BCF SDA_PORT1,SDA_PIN1
	GOTO b@slw
b@dal2 
    #IFDEF SDA_PORT2	
       BCF SDA_PORT2,SDA_PIN2
	   BSF 3,5
	   BCF SDA_PORT2,SDA_PIN2
       GOTO b@slw
	#ENDIF
b@dal3 
    #IFDEF SDA_PORT3	
       BCF SDA_PORT3,SDA_PIN3
	   BSF 3,5
	   BCF SDA_PORT3,SDA_PIN3
	#ENDIF	
b@slw
b@rst BCF 3,5
	RETURN
ENDASM

OVER_CODE: