int twi_write(uint8_t chip, uint8_t addr, uint8_t *buffer, int len)
{
if(NULL == buffer )
{
return 1;
}
/* start the read sequence with a address write!*/
if (!TWIM_Start (SlaveAddress, TWIM_WRITE))
{
TWIM_Stop ();
printf ("Could not start TWI Bus for READ\n");
return 1;
}
/* write address to slave, this points the address pointer a the given address on the slave */
if(!TWIM_Write(addr))
{
TWIM_Stop ();
printf ("Could not write the target address onto the bus \n");
return 1;
}
for(int i = 0; i < len; i++ )
{
if(!TWIM_Write(addr))
{
TWIM_Stop ();
printf ("Could not write the target address onto the bus \n");
return 1;
}
}
/* stop the write sequence */
TWIM_Stop (void);
return 0;
}
uint8_t I2C_Write(uint8_t reg, uint8_t value)
{
if (TWIM_Start(addr, TWIM_WRITE))
if (TWIM_Write(reg))
if (TWIM_Write(value))
{
TWIM_Stop();
return 1;
}
TWIM_Stop();
return 0;
}
uint8_t I2C_Read(uint8_t reg, uint8_t* buffer)
{
if (TWIM_Start(addr, TWIM_WRITE))
if (TWIM_Write(reg))
if (TWIM_Start(addr, TWIM_READ))
{
*buffer = TWIM_ReadNack();
TWIM_Stop();
return 1;
}
TWIM_Stop();
return 0;
}
int twi_read(uint8_t slaveAdress, uint8_t addr, uint8_t *buffer, int len)
{
if(NULL == buffer)
{
return 1;
}
/* start the read sequence with a address write!*/
if (!TWIM_Start (SlaveAddress, TWIM_WRITE))
{
TWIM_Stop ();
printf ("Could not start TWI Bus for READ\n");
return 1;
}
/* write address to slave, this points the address pointer a the given address on the slave */
if(!TWIM_Write(addr))
{
TWIM_Stop ();
printf ("Could not write the target address onto the bus \n");
return 1;
}
/* send repeated start sequence */
if (!TWIM_Start (SlaveAddress, TWIM_READ))
{
TWIM_Stop ();
printf ("Could not start TWI Bus for READ\n");
return 1;
}
/* read the data */
for(int i = 0; i < len; i++)
{
buffer[i] = TWIM_ReadAck();
}
/* the last byte is followed by a NACK */
TWIM_ReadNack();
/* Stop the */
TWIM_Stop();
return 0;
}
