NVIC_EnableIRQ(PIOD_IRQn) disables serial

Hey if the serial monitor (Serial) uses the following pins on the due

PIO_PA8 // PIN 0, URXD PIO_PA9 // PIN 1, UTXD

why would enabling the port D interrupt stop serial. ie NVIC_EnableIRQ(PIOD_IRQn)

Enabling PIOD interrupt doesn't stop Serial.

sorry it was writing to PIO_IER that is causing the issues

void InputRecorder::enable_trig_interrupts()
{
	TRIG_PIN_PORT->PIO_IDR = 0xFFFFFFFF;
	
	//TRIG_PIN_PORT->PIO_IER |= PIO_PB12;   <--- swapped to b port, this was the offending line
	
	if(actv_trigs[0] != 0)
	{
		pmc_enable_periph_clk(TRIG_PMC_CLK_ID);		
		trigs_are_enabled = true;
		NVIC_EnableIRQ(TRIG_PORT_IRQ);
	}
	
}