add timer-supported software i2c + arduino-nano timer

1 files changed, 28 insertions, 0 deletions

diff --git a/include/arch/arduino-nano/driver/timer.h b/include/arch/arduino-nano/driver/timer.h
new file mode 100644
index 0000000..267cb1d
--- /dev/null
+++ b/include/arch/arduino-nano/driver/timer.h
@@ -0,0 +1,28 @@
+#include <avr/io.h>
+#include <avr/interrupt.h>
+
+#define ON_TIMER_INTERRUPT ISR(TIMER0_COMPA_vect)
+
+class Timer {
+	private:
+		Timer(const Timer &copy);
+
+
+	public:
+		Timer() {}
+
+		inline void setup(unsigned char const frequency) {
+			OCR0A = frequency ? 255 / frequency : 1;
+			TCCR0A = _BV(WGM01);
+		}
+		inline void start(unsigned char const interrupt) {
+			TCNT0 = 0;
+			TCCR0B = _BV(CS01) | _BV(CS00);
+			if (interrupt) {
+				TIMSK0 = _BV(OCIE0A);
+			}
+		}
+		inline void stop() { TCCR0B = 0; TIMSK0 = 0; }
+};
+
+extern Timer timer;