--- /dev/null
+
+#ifndef __DELAY_H
+#define __DELAY_H
+
+#include <stdint.h>
+
+// Convenience Macros, for delay compatibility with AVR-GCC
+#define _delay_ms(val) delay( val )
+#define _delay_us(val) delayMicroseconds( val )
+
+
+// the systick interrupt is supposed to increment this at 1 kHz rate
+extern volatile uint32_t systick_millis_count;
+
+static inline uint32_t millis(void) __attribute__((always_inline, unused));
+static inline uint32_t millis(void)
+{
+ return systick_millis_count; // single aligned 32 bit is atomic;
+}
+
+
+static inline void delayMicroseconds(uint32_t) __attribute__((always_inline, unused));
+static inline void delayMicroseconds(uint32_t usec)
+{
+#if F_CPU == 96000000
+ uint32_t n = usec << 5;
+#elif F_CPU == 48000000
+ uint32_t n = usec << 4;
+#elif F_CPU == 24000000
+ uint32_t n = usec << 3;
+#endif
+ asm volatile(
+ "L_%=_delayMicroseconds:" "\n\t"
+ "subs %0, #1" "\n\t"
+ "bne L_%=_delayMicroseconds" "\n"
+ : "+r" (n) :
+ );
+}
+
+
+void yield(void) __attribute__ ((weak));
+
+uint32_t micros(void);
+
+void delay(uint32_t ms);
+
+#endif
+