Posted on February 25, 2016 at 10:36Hello everyone,
I have trying to reading axies from my accelerometer and I
keep getting 0 from my X Y Z axies at
movement.
Have someone encounter this problem?
My code:
void writeTo(u8 addressToWrite,uint8_t value, u8 address)
{
I2C_start(I2C3, address, I2C_Direction_Transmitter);
I2C_write(I2C3,addressToWrite);
I2C_write(I2C3,value);
I2C_stop(I2C3);
}
void setup()
{
writeTo(DATA_FORMAT, 0x0B, WRITE_ADDRESS_1);
writeTo(POWER_CTL, 0x08, WRITE_ADDRESS_1);
writeTo(INT_ENABLE, 0x80, WRITE_ADDRESS_1);
}
void ReadOperation(uint8_t address)
{
I2C_start(I2C3, WRITE_ADDRESS_1 , I2C_Direction_Transmitter);
I2C_write(I2C3,address);
I2C_stop(I2C3);
}
void ReadFromAccel()
{
ReadOperation(DATAX);
I2C_start(I2C3,READ_ADDRESS_1 , I2C_Direction_Receiver); //Normal Reading and then offset
Accel_Param.X_1 = I2C_read_nack(I2C3);
Delay(0xFFFFa);
ReadOperation(DATAY);
I2C_start(I2C3,READ_ADDRESS_1 , I2C_Direction_Receiver); //Normal Reading and then offset
Accel_Param.Y_1 = I2C_read_nack(I2C3);
Delay(0xFFFFa);
ReadOperation(DATAZ);
I2C_start(I2C3,READ_ADDRESS_1 , I2C_Direction_Receiver); //Normal Reading and then offset
Accel_Param.Z_1 = I2C_read_nack(I2C3);
Delay(0xFFFFa);
}
//void ReadFromAccel() //Try to read all the axies together
//{
// ReadOperation(DATAX);
// I2C_start(I2C3,READ_ADDRESS_1 , I2C_Direction_Receiver); //Normal Reading and then offset
// Accel_Param.X_1 = I2C_read_ack(I2C3);
// Accel_Param.Y_1 = I2C_read_ack(I2C3);
// Accel_Param.Z_1 = I2C_read_nack(I2C3);
// Delay(0xFFFFa);
//}
void ResetAccel()
{
int i;
inti_RCC();
init_I2C3();
GLB_DelayUs(1100); //need delay of 1.1 ms
setup();
GLB_DelayUs(11000); //need delay of 11.1 ms
for(i =0; i< 100; i++) //For noise
{
ReadFromAccel();
}
for(i =0; i< 100; i++)
{
ReadFromAccel();
}
}
void I2C_start(I2C_TypeDef* I2Cx, uint8_t address, uint8_t direction)
{
// wait until I2C3 is not busy anymore
while(I2C_GetFlagStatus(I2C3, I2C_FLAG_BUSY));
// Send I2C3 START condition
I2C_GenerateSTART(I2C3, ENABLE);
// wait for I2C3 EV5 --> Slave has acknowledged start condition
while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_MODE_SELECT));
// Send slave Address for write
I2C_Send7bitAddress(I2C3, address, direction);
if(direction == I2C_Direction_Transmitter){
while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
}
else if(direction == I2C_Direction_Receiver){
while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
}
}
void I2C_write(I2C_TypeDef* I2Cx, uint8_t data)
{
I2C_SendData(I2C3, data);
// wait for I2C3 EV8_2 --> byte has been transmitted
while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
}
void I2C_stop(I2C_TypeDef* I2Cx)
{
// Send I2C3 STOP Condition
I2C_GenerateSTOP(I2C3, ENABLE);
while(!I2C_CheckEvent(I2C3, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
}
// read one byte and don't request another byte, stop transmission
uint8_t I2C_read_nack(I2C_TypeDef* I2Cx){
uint8_t data;
// disable acknowledge of received data
// nack also generates stop condition after last byte received
I2C_AcknowledgeConfig(I2Cx, DISABLE);
I2C_GenerateSTOP(I2C3, ENABLE);
// wait until one byte has been received
while( !I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_RECEIVED) );
// read data from I2C data register and return data byte
data = I2C_ReceiveData(I2Cx);
return data;
}
