I2C master with Arduino I2C slave

[alec-g]

Hello all, I am having trouble getting the stm32plus i2c interface talking to an arudino which i have setup as an i2c slave. The arduino i2c slave is setup using the standard arduino Wire library, i have confirmed i am able to communicate to the slave using another arduino and access internal registers, however no matter what i try i cannot get my stm32f4 to read or write registers on this arduino slave. I have setup a very simple i2c master on the stm32:

static const uint8_t SLAVE_ADDRESS = 0x5F;
static const uint8_t CURRENT_SPEED = 0x14;

struct I2CPinPackage
{
  enum
  {
    Port_SCL=GPIOF_BASE,
    Port_SDA=GPIOH_BASE,
    Pin_SCL=GPIO_Pin_1,
    Pin_SDA=GPIO_Pin_5
  };
};

typedef stm32plus::I2C2_Custom<I2CPinPackage, stm32plus::I2CSingleByteMasterPollingFeature> I2C;

int main() {
  stm32plus::Nvic::initialise();
  stm32plus::MillisecondTimer::initialise();

  I2C* i2c_;

  I2C::Parameters i2c_params;
  i2c_params.i2c_clockSpeed = 50000;

  i2c_ = new I2C(i2c_params);
  i2c_->setSlaveAddress(SLAVE_ADDRESS);
  i2c_->enablePeripheral();

  while(1) {
    uint8_t read_buffer;
    if (!(i2c_->readBytes(CURRENT_SPEED, &read_buffer, 1))) {
      // Error!
    }
  }

  // not reached
  return 0;
}

I have tripple checked the pin mapping is correct, i have even tried alternative pin mappings supported by my board, is there something i am doing wrong in the initialisation? Or is there something special about the arduino Wire library and its protocol that the stm32plus library does not accomodate for? Any help is appreciated.

[alec-g]

Solved! I am unsure why, but i had to change the slave address from 0x5F to 0x5F<<1, i guess something to do with 7-bit slave addressing?