iic.c

ucosii在codefire系列的5222x上的移植

/*
 * File:		I2C.c
 * Purpose:		I2C transfer functions and interrupt handler
 *
 * Notes:		
 *  
 */
 
#include "common.h"

#if __cplusplus
extern "C" 
{
#endif

void iic_delay(void);
#define nop()       asm( nop)

/********************************************************************/

/*
 * I2Cinit: I2C initilazation as master
 *
 * Parameters: None.
 *
 * Return : None.
 */
void I2Cinit()
{
	uint8 temp;
	
	/* Enable the I2C signals */
	MCF_GPIO_PASPAR |= ( MCF_GPIO_PASPAR_SDA_SDA
							 | MCF_GPIO_PASPAR_SCL_SCL);
							 
	/* set the frequency near 400KHz, see MCF52223RM table for details */ 
	MCF_I2C_I2FDR = MCF_I2C_I2FDR_IC(0x32);
	/* start the module */
	MCF_I2C_I2CR = 0 | MCF_I2C_I2CR_IEN;
	
	/* if bit busy set, send a stop condition to slave module */
	if( MCF_I2C_I2SR & MCF_I2C_I2SR_IBB)
	{
		MCF_I2C_I2CR = 0;						/* clear control register */
		MCF_I2C_I2CR = MCF_I2C_I2CR_IEN |		/* enable module */
					   MCF_I2C_I2CR_MSTA;		/* send a START conditionn */
		temp = MCF_I2C_I2DR;					/* dummy read */
		MCF_I2C_I2SR = 0;						/* clear status register */
		MCF_I2C_I2CR = 0;						/* clear control register */
		MCF_I2C_I2CR = 0 | MCF_I2C_I2CR_IEN;	/* enable the module again */
	}
	return;	
}
/*
 * I2CreceiveByte: I2C read byte
 *
 * Parameters: address: address to read
 *			   id: I2C device to read
 *
 * Return : data: byte read it from device
 */
uint8 I2CreceiveByte(uint8 address, uint8 id)
{
	uint8 data;
	
	MCF_I2C_I2CR |= MCF_I2C_I2CR_MTX;			/* setting in Tx mode */
	/* send start condition */
	MCF_I2C_I2CR |= MCF_I2C_I2CR_MSTA;
	MCF_I2C_I2DR = id;							/* devide ID to write */
	/* wait until one byte transfer completion */
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;
	MCF_I2C_I2DR = address;						/* memory address */
	/* wait until one byte transfer completion */
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;	 	
	MCF_I2C_I2CR |= MCF_I2C_I2CR_RSTA;			/* resend start */
	MCF_I2C_I2DR = (uint8)(id | 0x01);					/* device id to read */
	/* wait until one byte transfer completion */
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;
	MCF_I2C_I2CR &= ~MCF_I2C_I2CR_MTX;			/* setting in Rx mode */
	MCF_I2C_I2CR |= MCF_I2C_I2CR_TXAK;			/* send NO ACK */
	data = MCF_I2C_I2DR;						/* dummy read */
	/* wait until one byte transfer completion */
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;
	data = MCF_I2C_I2DR;						/* read data received */
	/* wait until one byte transfer completion */
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;
	/* generates stop condition */
	MCF_I2C_I2CR &= ~MCF_I2C_I2CR_MSTA;
	/* send the received data */
	return data;
}
/*
 * I2CsendByte: send byte to I2C device
 *
 * Parameters: data: byte to write
 *			   address: address to write
 *			   id: I2C device to write
 *
 * Return : None.
 */
void I2CsendByte(uint8 data, uint8 address, uint8 id)
{
	mcf5xxx_irq_disable();
	MCF_I2C_I2CR |= MCF_I2C_I2CR_MTX;			/* setting in Tx mode */
	/* generates start condition */
	MCF_I2C_I2CR |= MCF_I2C_I2CR_MSTA;
	MCF_I2C_I2DR = id;							/* set devide ID to write */
	/* wait until one byte transfer completion */
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;
	MCF_I2C_I2DR = address;						/* memory address */
	iic_delay();
	/* wait until one byte transfer completion */
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;	
	MCF_I2C_I2DR = data;						/* memory data */
	/* wait until one byte transfer completion */
	iic_delay();
	while( !(MCF_I2C_I2SR & MCF_I2C_I2SR_IIF ))
	;
	/* clear the completion transfer flag */
	MCF_I2C_I2SR &= ~MCF_I2C_I2SR_IIF;	
	/* generates stop condition */
	MCF_I2C_I2CR &= ~MCF_I2C_I2CR_MSTA;
	mcf5xxx_irq_enable();
	return;
}

/********************************************************************/
void
iic_delay(void)
{
	uint16 i;
	/* Wait for a bit */
	i=500;
	while(i--)
	nop();
}
void
iic_check(void)
{
	uint8 i;
	for (i=16;i<23;i++)
	{
   	printf("max3353e reg 0x%02x = 0x%02x\n",i,I2CreceiveByte(i,Slave_Addr));
   	if (i== 0x11)		
   		i=0x12;
   	if (i== 0x07)		
   		i=0x0F;
	iic_delay();
	}
    printf("\n");
}

#if __cplusplus
}
#endif