/* DAC Channel Trigger Enable. 
Enable a digital to analog converter channel external trigger mode. This allows an external trigger to initiate register transfers from the buffer register to the DAC output register, followed by a DMA transfer to the buffer register if DMA is enabled. The trigger source must also be selected. */
void dac_trigger_enable(data_channel dac_channel)
/* DAC Channel Trigger Enable. 
Enable a digital to analog converter channel external trigger mode. This allows an external trigger to initiate register transfers from the buffer register to the DAC output register, followed by a DMA transfer to the buffer register if DMA is enabled. The trigger source must also be selected. */
void dac_trigger_enable(data_channel dac_channel)
{
	switch (dac_channel) {
	case CHANNEL_1:
		DAC_CR |= DAC_CR_TEN1;
		break;
	case CHANNEL_2:
		DAC_CR |= DAC_CR_TEN2;
		break;
	case CHANNEL_D:
		DAC_CR |= (DAC_CR_TEN1 | DAC_CR_TEN2);
		break;
	}
}