diff --git a/timer.c b/timer.c
index ce77f6f..b58761b 100644
--- a/timer.c
+++ b/timer.c
@@ -55,7 +55,7 @@ ISR(TIMER1_COMPA_vect) {
 
 		// disable this interrupt. if we set a new timeout, it will be re-enabled when appropriate
 		TIMSK1 &= ~MASK(OCIE1A);
-		
+
 		// stepper tick
 		queue_step();
 
@@ -130,7 +130,7 @@ void timer_init() {
 	as late as possible. If you use it from outside the step interrupt,
 	do a sei() after it to make the interrupt actually fire.
 */
-char timer_set(int32_t delay, char check_short) {
+uint8_t timer_set(int32_t delay, uint8_t check_short) {
 	uint16_t step_start = 0;
 	#ifdef ACCELERATION_TEMPORAL
 	uint16_t current_time;
@@ -182,7 +182,7 @@ char timer_set(int32_t delay, char check_short) {
 
 	// Enable this interrupt, but only do it after disabling
 	// global interrupts (see above). This will cause push any possible
-	// timer1a interrupt to the far side of the return, protecting the 
+	// timer1a interrupt to the far side of the return, protecting the
 	// stack from recursively clobbering memory.
 	TIMSK1 |= MASK(OCIE1A);
   #ifdef SIMULATOR
diff --git a/timer.h b/timer.h
index 1ba70ef..fb0048b 100644
--- a/timer.h
+++ b/timer.h
@@ -2,10 +2,6 @@
 #define	_TIMER_H
 
 #include	<stdint.h>
-#ifdef __AVR__
-#include	<avr/io.h>
-#endif
-#include "simulator.h"
 
 
 // time-related constants
@@ -21,12 +17,9 @@
 #define TICK_TIME_MS (TICK_TIME / (F_CPU / 1000))
 
 
-/*
-timer stuff
-*/
-void timer_init(void) __attribute__ ((cold));
+void timer_init(void);
 
-char timer_set(int32_t delay, char check_short);
+uint8_t timer_set(int32_t delay, uint8_t check_short);
 
 void timer_stop(void);