.INCLUDE "M32DEF.INC"

	LDI	R21,HIGH(RAMEND)
	OUT	SPH,R21
	LDI	R21,LOW(RAMEND)
	OUT	SPL,R21

	LDI	R21,$FF			
	OUT	DDRA, R21		

	CALL	I2C_INIT	
	CALL	I2C_START	
	LDI	R27, 0b11010001	
	CALL	I2C_WRITE	
	CALL	I2C_READ	
	OUT	PORTA,R27		
	CALL I2C_STOP		

HERE:
	RJMP	HERE


;*********************************************************
I2C_INIT:
	LDI	R21, 0
	OUT	TWSR,R21
	LDI	R21, $47
	OUT	TWBR,R21			
	LDI	R21, (1<<TWEN)		
	OUT	TWCR,R21			
	RET

;*********************************************************
I2C_START:
	LDI	R21, (1<<TWINT)|(1<<TWSTA)|(1<<TWEN)
	OUT	TWCR,R21			
WAIT1:
	IN	R21, TWCR			
	SBRS	R21, TWINT		
	RJMP	WAIT1			
	RET

;*********************************************************
I2C_READ:
	LDI	R21,(1<<TWINT)|(1<<TWEN)
	OUT	TWCR, R21		
WAIT2:	
	IN	R21, TWCR	
	SBRS	R21, TWINT
	RJMP	WAIT2		
	IN	R27, TWDR		
	RET

;*********************************************************
I2C_WRITE:
	OUT	TWDR, R27
	LDI	R21, (1<<TWINT)|(1<<TWEN)
	OUT	TWCR, R21
WAIT3:
	IN	R21, TWCR
	SBRS	R21, TWINT			
	RJMP	WAIT3				
	RET

;*********************************************************
I2C_STOP:
	LDI	R21, (1<<TWINT)|(1<<TWSTO)|(1<<TWEN)
	OUT	TWCR, R21		
	RET