Hi guys,
I'm using the latest ST generated I2C hal driver on an STM32L0. On my I2C master, I'm requesting to read from a register, which sends the following sequence:
Start -> Address (W) -> Register 1B -> Stop -> Start -> Address (R) -> Data 4B -> Stop
On the slave end, it's receiving the address, which is triggering the address callback, it's matching, it requests to receive 1 Byte via HAL_I2C_Slave_Seq_Receive_IT(), it receives this, the listen complete callback is then raised which re-enables the listen callback. It then receives and seems to correctly handle the request for the slave to send the 4 data bytes, however what ends up on the bus is 0xFF for each byte. I'm unsure why the data isn't being transmitted.
I do have clock stretching turned off (as master doesn't support it) but have tried this at low speeds such as 10KHz.
My code is implemented as follows:
// Setup
while( HAL_OK != HAL_I2C_EnableListen_IT( &hi2c1 ) );
void HAL_I2C_AddrCallback(I2C_HandleTypeDef *hi2c, uint8_t TransferDirection, uint16_t AddrMatchCode)
{
if(AddrMatchCode == 4)
{
if( TransferDirection == I2C_DIRECTION_TRANSMIT )
{
while(HAL_I2C_Slave_Seq_Receive_IT( &hi2c1, buffer, 1, I2C_FIRST_FRAME) != HAL_OK);
mode = I2C_MODE_SET_REGISTER;
}
else
{
if( mode == I2C_MODE_RECEIVE_REGISTER )
{
buffer[0] = 0xAA;
buffer[1] = 0xAA;
buffer[2] = 0xAA;;
buffer[3] = 0xAA;
while(HAL_I2C_Slave_Seq_Receive_IT( &hi2c1, buffer, 4, I2C_LAST_FRAME) != HAL_OK);
mode = I2C_MODE_NONE;
}
}
}
}
void HAL_I2C_ListenCpltCallback(I2C_HandleTypeDef *hi2c)
{
while( HAL_OK != HAL_I2C_EnableListen_IT( &hi2c1 ) );
}
void HAL_I2C_SlaveRxCpltCallback( I2C_HandleTypeDef *hi2c )
{
switch( mode )
{
case I2C_MODE_SET_REGISTER:
currentRegister = buffer[0];
mode = I2C_MODE_RECEIVE_REGISTER;
break;
default: break;
}
}
Any ideas?
Many thanks
