src/machine/machine_stm32l4x2.go


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//go:build stm32l4x2

package machine

// Peripheral abstraction layer for the stm32l4x2

func CPUFrequency() uint32 {
	return 80000000
}

// Internal use: configured speed of the APB1 and APB2 timers, this should be kept
// in sync with any changes to runtime package which configures the oscillators
// and clock frequencies
const APB1_TIM_FREQ = 80e6 // 80MHz
const APB2_TIM_FREQ = 80e6 // 80MHz

//---------- I2C related code

// Gets the value for TIMINGR register
func (i2c *I2C) getFreqRange(br uint32) uint32 {
	// These are 'magic' values calculated by STM32CubeMX
	// for 80MHz PCLK1.
	// TODO: Do calculations based on PCLK1
	switch br {
	case 10 * KHz:
		return 0xF010F3FE
	case 100 * KHz:
		return 0x10909CEC
	case 400 * KHz:
		return 0x00702991
	case 500 * KHz:
		return 0x00300E84
	default:
		return 0
	}
}