/* Read num bytes starting from regAddrStart. Each subsequent byte will be from the register above (newRegPtr = oldRegPtr + 1).
*
* Input: regAddrStart The register address to start reading bytes from
* data Location to store read data
* num The number of registers to be read
* Return: 0 Succeeded
* >0 Failed, see handle_error() for relavant error codes
*/
uint8_t twi_read_bytes(uint8_t regAddrStart, uint8_t *data, uint8_t num) {
uint8_t i, error;
/* Transmit start condition. */
if((error = twi_start())) return error;
/* Transmit slave address and write bit. */
if((error = twi_sla_w(IMU_ADDR))) return error;
/* Transmit to slave the register to be read. */
if((error = twi_write(regAddrStart))) return error;
/* Transmit repeated start condition. */
if((error = twi_start_r())) return error;
/* Transmit slave address and read bit. */
if((error = twi_sla_r(IMU_ADDR))) return error;
/* Read data from slave. */
for(i = 0; i < num; i++) {
if(i == num - 1) {
/* Last byte, return NACK. */
if((error = twi_read_nack(&data[i]))) return error;
} else {
if((error = twi_read_ack(&data[i]))) return error;
}
}
/* Transmit stop condition. */
twi_stop();
return 0;
}
uint8_t twi_read_byte(void)
{
//uint8_t databyte;
twi_start();
if (twi_get_status() != 0x08)
return ERROR;
//select devise and send A2 A1 A0 address bits
twi_write(0xD0);
if (twi_get_status() != 0x18)
return ERROR;
twi_write(0x01);
if (twi_get_status() != 0x18)
return ERROR;
twi_read_ack();
twi_write(0xD1);
if (twi_get_status() != 0x18)
return ERROR;
twi_start();
twi_read_nack();
if (twi_get_status() != 0x58)
return ERROR;
twi_stop();
return SUCCESS;
}
/**
* Function : twi::twi_read_bytes()
* Purpose : To receive a byte array.
* Parameters : - data : The data array.
* - size : The size of the array.
* Returns : Nothing.
* Notes : None.
**/
void twi_read_bytes(BYTE *data, BYTE size)
{
for(BYTE i=0 ; i<size ; i++)
{
if(i < (size - 1)) data[i] = twi_read_ack();
else data[i] = twi_read_nak();
}
}
