From ece23822106bb4a005fd64299cddeec97a9f5307 Mon Sep 17 00:00:00 2001
From: Yann Dirson <ydirson@free.fr>
Date: Tue, 29 Nov 2011 23:46:11 +0100
Subject: [PATCH] Add a simple Timer example for CTC mode.

---
 .../Basics/1.Getting Started/Timer/Timer.pde  | 40 +++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 framework/examples/Basics/1.Getting Started/Timer/Timer.pde

diff --git a/framework/examples/Basics/1.Getting Started/Timer/Timer.pde b/framework/examples/Basics/1.Getting Started/Timer/Timer.pde
new file mode 100644
index 0000000..72f2f13
--- /dev/null
+++ b/framework/examples/Basics/1.Getting Started/Timer/Timer.pde	
@@ -0,0 +1,40 @@
+/**
+ * Blink the Wiring board LED
+ * by Yann Dirson <ydirson@free.fr>
+ *
+ * turns on and off the Wiring board LED, with
+ * intervals of 1 second, using a 16bit timer
+ * interrupt to avoid burning electrons with active wait.
+ *
+ * For the Wiring boards v1 the on-board LED is on pin 48,
+ * on Wiring S the on-board LED is on pin 15.
+ * it is also possible to use the WLED constant with the
+ * digitalWrite command: digitalWrite(WLED, HIGH). WLED will be the
+ * correct pin in the current board selected in the
+ * Tools -> Board menu.
+ */
+
+void timer1_irq()
+{
+  static int led = LOW;
+  led = (led==LOW) ? HIGH : LOW;
+  digitalWrite(WLED, led);
+}
+
+void setup() {
+  pinMode(WLED, OUTPUT);
+
+  Timer1.setMode(0b0100);  // CTC mode with OCR1A
+  Timer1.setClockSource(CLOCK_PRESCALE_1024);
+  Timer1.setOCR(CHANNEL_A, F_CPU/1024);
+  Timer1.attachInterrupt(INTERRUPT_COMPARE_MATCH_A, timer1_irq);
+  Timer1.enableInterrupt(INTERRUPT_COMPARE_MATCH_A);
+
+  // disable unused clocks
+  Timer0.setClockSource(CLOCK_STOP);
+  Timer3.setClockSource(CLOCK_STOP);
+}
+
+void loop() {
+  sleep_mode();
+}