Fix I2C4 not working

[AndrewCapon]

Use GPIO_AF6_I2C4 for alternate function

[github-actions]

Test Results

151 tests  ±0   151 ✅ ±0   0s ⏱️ ±0s
 16 suites ±0     0 💤 ±0 
  1 files   ±0     0 ❌ ±0 

Results for commit b1c10b6. ± Comparison against base commit f7727ed.

[beserge]

Unable to confirm this works. Tested on the daisy field, replaced I2C1 with I2C4, which should work since they share pins, but it stops working. More digging may be needed.

[AndrewCapon]

I don't think they share pins, is the field different to the seed?

This works here for both i2c1 and i2c4 on the seed:

#define TEST_I2C 4
int main(void)
{
	hw.Init();

	I2CHandle                i2c;
        I2CHandle::Config   i2c_config;

#if TEST_I2C == 4
	i2c_config.periph         = I2CHandle::Config::Peripheral::I2C_4;
	i2c_config.speed          = I2CHandle::Config::Speed::I2C_100KHZ;
	i2c_config.mode           = I2CHandle::Config::Mode::I2C_MASTER;
	i2c_config.pin_config.scl = hw.GetPin(13);
	i2c_config.pin_config.sda = hw.GetPin(14);
	i2c_config.address        = 0x3C;	
#else
	i2c_config.periph         = I2CHandle::Config::Peripheral::I2C_1;
	i2c_config.speed          = I2CHandle::Config::Speed::I2C_100KHZ;
	i2c_config.mode           = I2CHandle::Config::Mode::I2C_MASTER;
	i2c_config.pin_config.scl = hw.GetPin(11);
	i2c_config.pin_config.sda = hw.GetPin(12);
	i2c_config.address        = 0x3C;	
#endif	
	i2c.Init(i2c_config);

	uint8_t data;
	while(1)
		i2c.TransmitBlocking(i2c_config.address, &data, 1, 1000); 

	return 0;
}

[beserge]

Sorry for the back and forth, I was able to retest and confirm this is working. Thanks for your contribution!