merge #437

sam.cpp

@@ -0,0 +1,102 @@
+// Support routines for SAM processor boards
+
+#include "IRremote.h"
+#include "IRremoteInt.h"
+
+#if defined(ARDUINO_ARCH_SAM) || defined(ARDUINO_ARCH_SAMD)
+
+// "Idiot check"
+#ifdef USE_DEFAULT_ENABLE_IR_IN
+#error Must undef USE_DEFAULT_ENABLE_IR_IN
+#endif
+
+//+=============================================================================
+// ATSAMD Timer setup & IRQ functions
+//
+
+// following based on setup from GitHub jdneo/timerInterrupt.ino
+
+static void setTimerFrequency(int frequencyHz)
+{
+	int compareValue = (SYSCLOCK / (TIMER_PRESCALER_DIV * frequencyHz)) - 1;
+	//Serial.println(compareValue);
+	TcCount16* TC = (TcCount16*) TC3;
+	// Make sure the count is in a proportional position to where it was
+	// to prevent any jitter or disconnect when changing the compare value.
+	TC->COUNT.reg = map(TC->COUNT.reg, 0, TC->CC[0].reg, 0, compareValue);
+	TC->CC[0].reg = compareValue;
+	//Serial.print("COUNT.reg ");
+	//Serial.println(TC->COUNT.reg);
+	//Serial.print("CC[0].reg ");
+	//Serial.println(TC->CC[0].reg);
+	while (TC->STATUS.bit.SYNCBUSY == 1);
+}
+
+static void startTimer()
+{
+	REG_GCLK_CLKCTRL = (uint16_t) (GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK0 | GCLK_CLKCTRL_ID_TCC2_TC3);
+	while (GCLK->STATUS.bit.SYNCBUSY == 1); // wait for sync
+
+	TcCount16* TC = (TcCount16*) TC3;
+
+	TC->CTRLA.reg &= ~TC_CTRLA_ENABLE;
+	while (TC->STATUS.bit.SYNCBUSY == 1); // wait for sync
+
+	// Use the 16-bit timer
+	TC->CTRLA.reg |= TC_CTRLA_MODE_COUNT16;
+	while (TC->STATUS.bit.SYNCBUSY == 1); // wait for sync
+
+	// Use match mode so that the timer counter resets when the count matches the compare register
+	TC->CTRLA.reg |= TC_CTRLA_WAVEGEN_MFRQ;
+	while (TC->STATUS.bit.SYNCBUSY == 1); // wait for sync
+
+	// Set prescaler to 1024
+	//TC->CTRLA.reg |= TC_CTRLA_PRESCALER_DIV1024;
+	TC->CTRLA.reg |= TC_CTRLA_PRESCALER_DIV64;
+	while (TC->STATUS.bit.SYNCBUSY == 1); // wait for sync
+
+	setTimerFrequency(1000000 / USECPERTICK);
+	
+	// Enable the compare interrupt
+	TC->INTENSET.reg = 0;
+	TC->INTENSET.bit.MC0 = 1;
+
+	NVIC_EnableIRQ(TC3_IRQn);
+
+	TC->CTRLA.reg |= TC_CTRLA_ENABLE;
+	while (TC->STATUS.bit.SYNCBUSY == 1); // wait for sync
+}
+
+//+=============================================================================
+// initialization
+//
+
+void IRrecv::enableIRIn()
+{
+	// Interrupt Service Routine - Fires every 50uS
+	//Serial.println("Starting timer");
+	startTimer();
+	//Serial.println("Started timer");
+
+	// Initialize state machine variables
+	irparams.rcvstate = STATE_IDLE;
+	irparams.rawlen = 0;
+
+	// Set pin modes
+	pinMode(irparams.recvpin, INPUT);
+}
+
+void irs(); // Defined in IRRemote as ISR(TIMER_INTR_NAME)
+
+void TC3_Handler(void)
+{
+	TcCount16* TC = (TcCount16*) TC3;
+	// If this interrupt is due to the compare register matching the timer count
+	// we toggle the LED.
+	if (TC->INTFLAG.bit.MC0 == 1) {
+		TC->INTFLAG.bit.MC0 = 1;
+		irs();
+	}
+}
+
+#endif // defined(ARDUINO_ARCH_SAM) || defined(ARDUINO_ARCH_SAMD)