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diff --git a/BaseMegaFirmware/GCC/timebase.c b/BaseMegaFirmware/GCC/timebase.c
new file mode 100644
index 0000000..92bf015
--- /dev/null
+++ b/BaseMegaFirmware/GCC/timebase.c
@@ -0,0 +1,87 @@
+// Copyright (c) 2007, 2008 Martin Thomas - BSD-license
+// 10 ms timebase with 
+// 8bit timer-counter #0 in CTC-mode on ATmega644
+
+#include <stdint.h>
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include "timebase.h"
+
+#include "key_io.h" /* keys callback/debouce */
+
+#define COUNTER_IS_16BIT   0
+#define PRESCALER   1024UL
+
+#if TIMEBASE_DELTAT_MS != 10
+#warning "code prepared for 10ms tick"
+#endif
+
+#define TIMERFREQ   (1000/TIMEBASE_DELTAT_MS) /* Hz */
+#define OCRMATCHVAL ( (F_CPU*10/PRESCALER/TIMERFREQ+5)/10 - 1 )
+
+#if COUNTER_IS_16BIT
+ /* 16 bit counter */
+#define OCR_MATCH_MAX 0xfffe
+#else
+/* 8 bit counter */
+#define OCR_MATCH_MAX 0xfe
+#endif /* COUNTER_IS_16BIT */
+#define OCR_MATCH_MIN 0x02
+
+#if ( OCRMATCHVAL > OCR_MATCH_MAX )
+#error "PRESCALER too small or F_CPU too high"
+#endif
+#if ( OCRMATCHVAL < 2 )
+#error "PRESCALER too large or F_CPU too low"
+#endif
+
+volatile uint16_t timebase_tick;
+
+ISR(TIMER0_COMPA_vect)
+{
+	timebase_tick++;
+
+	key_io_callback();
+}
+
+void timebase_init(void)
+{
+	uint8_t sreg;
+
+	sreg=SREG;
+	cli();
+
+	// init Timer 0 Mode 4 - CTC with interrupt on compare-match 
+	
+	TCCR0A = (1<<WGM01);
+#if (PRESCALER == 1024)
+	TCCR0B = (1<<CS02) | (1<<CS00);
+#else
+#error "PRESCALER settings not available"
+#endif
+	
+	OCR0A  = OCRMATCHVAL; // match-value
+	
+	TCNT0  = 0;           // reset timer-counter
+	TIFR0  = (1<<OCF0A);  // clear interrupt
+	TIMSK0 = (1<<OCIE0A); // enabled matchA interrupt
+
+	timebase_tick = 0;
+
+	SREG=sreg;
+}
+
+uint16_t timebase_get_tick(void)
+{
+	uint8_t sreg;
+	uint16_t res;
+
+	sreg = SREG;
+	cli();
+
+	res = timebase_tick;
+
+	SREG=sreg;
+
+	return res;
+}