OPAMP Configuration Code

Just a few lines of code are required to configure the OPAMP peripheral to implement the constant-current driver:

	// Set up the timebase of the OPAMP peripheral
	OPAMP.TIMEBASE = 3; // Number of CLK_PER cycles that equal one us, minus one (4-1=3)
	
	//Connect OP0 to wiper and pin connected to sense resistor
	OPAMP.OP0INMUX = OPAMP_OP0INMUX_MUXPOS_WIP_gc | OPAMP_OP0INMUX_MUXNEG_INN_gc;
	//Connect resistor ladder to VDD and ground so the wiper functions as a voltage divider
	OPAMP.OP0RESMUX = OPAMP_OP0RESMUX_MUXBOT_GND_gc | OPAMP_OP0RESMUX_MUXWIP_WIP7_gc | OPAMP_OP0RESMUX_MUXTOP_VDD_gc;
	// Configure OP0 Control A
	OPAMP.OP0CTRLA = OPAMP_OP0CTRLA_OUTMODE_NORMAL_gc | OPAMP_ALWAYSON_bm;
	
	// Enable the OPAMP peripheral
	OPAMP.CTRLA = OPAMP_ENABLE_bm;