diff --git a/include/btstack/run_loop.h b/include/btstack/run_loop.h
index 077e8db03..d7df0367e 100644
--- a/include/btstack/run_loop.h
+++ b/include/btstack/run_loop.h
@@ -113,7 +113,7 @@ uint32_t embedded_get_ticks(void);
 // just before entering sleep mode. Has to be called by the interupt
 // handler of a data source to signal the run loop that a new data 
 // is available.
-void     embedded_trigger(void);    
+void embedded_trigger(void);    
 #endif
 #if defined __cplusplus
 }
diff --git a/src/run_loop.c b/src/run_loop.c
index 513ea496b..8ade4085b 100644
--- a/src/run_loop.c
+++ b/src/run_loop.c
@@ -98,6 +98,11 @@ int run_loop_remove_data_source(data_source_t *ds){
     return the_run_loop->remove_data_source(ds);
 }
 
+void run_loop_set_timer(timer_source_t *a, uint32_t timeout_in_ms){
+    run_loop_assert();
+    the_run_loop->set_timer(a, timeout_in_ms);
+}
+
 /**
  * Add timer to run_loop (keep list sorted)
  */
diff --git a/src/run_loop_cocoa.m b/src/run_loop_cocoa.m
index 93009522a..f87181b82 100644
--- a/src/run_loop_cocoa.m
+++ b/src/run_loop_cocoa.m
@@ -138,6 +138,17 @@ int  cocoa_remove_timer(timer_source_t * ts){
 	return 0;
 }
 
+// set timer
+static void cocoa_set_timer(timer_source_t *a, uint32_t timeout_in_ms){
+    gettimeofday(&a->timeout, NULL);
+    a->timeout.tv_sec  +=  timeout_in_ms / 1000;
+    a->timeout.tv_usec += (timeout_in_ms % 1000) * 1000;
+    if (a->timeout.tv_usec  > 1000000) {
+        a->timeout.tv_usec -= 1000000;
+        a->timeout.tv_sec++;
+    }
+}
+
 void cocoa_init(void){
 }
 
@@ -155,9 +166,10 @@ run_loop_t run_loop_cocoa = {
     &cocoa_init,
     &cocoa_add_data_source,
     &cocoa_remove_data_source,
+    &cocoa_set_timer,
     &cocoa_add_timer,
     &cocoa_remove_timer,
     &cocoa_execute,
-    &cocoa_dump_timer
+    &cocoa_dump_timer,
 };
 
diff --git a/src/run_loop_embedded.c b/src/run_loop_embedded.c
index 456985f14..93d309bf4 100644
--- a/src/run_loop_embedded.c
+++ b/src/run_loop_embedded.c
@@ -73,31 +73,31 @@ static uint32_t system_ticks;
 
 static int trigger_event_received = 0;
 
-/**
- * trigger run loop iteration
- */
-void embedded_trigger(void){
-    trigger_event_received = 1;
-}
-
 /**
  * Add data_source to run_loop
  */
-void embedded_add_data_source(data_source_t *ds){
+static void embedded_add_data_source(data_source_t *ds){
     linked_list_add(&data_sources, (linked_item_t *) ds);
 }
 
 /**
  * Remove data_source from run loop
  */
-int embedded_remove_data_source(data_source_t *ds){
+static int embedded_remove_data_source(data_source_t *ds){
     return linked_list_remove(&data_sources, (linked_item_t *) ds);
 }
 
+// set timer
+static void embedded_set_timer(timer_source_t *ts, uint32_t timeout_in_ms){
+    uint32_t ticks = embedded_ticks_for_ms(timeout_in_ms);
+    if (ticks == 0) ticks++;
+    ts->timeout = system_ticks + ticks; 
+}
+
 /**
  * Add timer to run_loop (keep list sorted)
  */
-void embedded_add_timer(timer_source_t *ts){
+static void embedded_add_timer(timer_source_t *ts){
 #ifdef HAVE_TICK
     linked_item_t *it;
     for (it = (linked_item_t *) &timers; it->next ; it = it->next){
@@ -115,7 +115,7 @@ void embedded_add_timer(timer_source_t *ts){
 /**
  * Remove timer from run loop
  */
-int embedded_remove_timer(timer_source_t *ts){
+static int embedded_remove_timer(timer_source_t *ts){
 #ifdef HAVE_TICK    
     // log_info("Removed timer %x at %u\n", (int) ts, (unsigned int) ts->timeout.tv_sec);
     return linked_list_remove(&timers, (linked_item_t *) ts);
@@ -124,7 +124,7 @@ int embedded_remove_timer(timer_source_t *ts){
 #endif
 }
 
-void embedded_dump_timer(void){
+static void embedded_dump_timer(void){
 #ifdef HAVE_TICK
 #ifdef ENABLE_LOG_INFO 
     linked_item_t *it;
@@ -140,7 +140,7 @@ void embedded_dump_timer(void){
 /**
  * Execute run_loop once
  */
-void embedded_execute_once(void) {
+static void embedded_execute_once(void) {
     data_source_t *ds;
 
     // process data sources
@@ -173,7 +173,7 @@ void embedded_execute_once(void) {
 /**
  * Execute run_loop
  */
-void embedded_execute(void) {
+static void embedded_execute(void) {
     while (1) {
         embedded_execute_once();
     }
@@ -192,16 +192,16 @@ uint32_t embedded_get_ticks(void){
 uint32_t embedded_ticks_for_ms(uint32_t time_in_ms){
     return time_in_ms / hal_tick_get_tick_period_in_ms();
 }
-
-// set timer
-void run_loop_set_timer(timer_source_t *ts, uint32_t timeout_in_ms){
-    uint32_t ticks = embedded_ticks_for_ms(timeout_in_ms);
-    if (ticks == 0) ticks++;
-    ts->timeout = system_ticks + ticks; 
-}
 #endif
 
-void embedded_init(void){
+/**
+ * trigger run loop iteration
+ */
+void embedded_trigger(void){
+    trigger_event_received = 1;
+}
+
+static void embedded_init(void){
 
     data_sources = NULL;
 
@@ -217,8 +217,9 @@ const run_loop_t run_loop_embedded = {
     &embedded_init,
     &embedded_add_data_source,
     &embedded_remove_data_source,
+    &embedded_set_timer,
     &embedded_add_timer,
     &embedded_remove_timer,
     &embedded_execute,
-    &embedded_dump_timer
+    &embedded_dump_timer,
 };
diff --git a/src/run_loop_posix.c b/src/run_loop_posix.c
index 6cbb5045d..4aa0a707b 100644
--- a/src/run_loop_posix.c
+++ b/src/run_loop_posix.c
@@ -50,7 +50,9 @@
 #include <stdlib.h>
 #include <stdio.h>
 
-void posix_dump_timer(void);
+static void posix_dump_timer(void);
+static int posix_timeval_compare(struct timeval *a, struct timeval *b);
+static int posix_timer_compare(timer_source_t *a, timer_source_t *b);
 
 // the run loop
 static linked_list_t data_sources;
@@ -60,7 +62,7 @@ static linked_list_t timers;
 /**
  * Add data_source to run_loop
  */
-void posix_add_data_source(data_source_t *ds){
+static void posix_add_data_source(data_source_t *ds){
     data_sources_modified = 1;
     // log_info("posix_add_data_source %x with fd %u\n", (int) ds, ds->fd);
     linked_list_add(&data_sources, (linked_item_t *) ds);
@@ -69,7 +71,7 @@ void posix_add_data_source(data_source_t *ds){
 /**
  * Remove data_source from run loop
  */
-int posix_remove_data_source(data_source_t *ds){
+static int posix_remove_data_source(data_source_t *ds){
     data_sources_modified = 1;
     // log_info("posix_remove_data_source %x\n", (int) ds);
     return linked_list_remove(&data_sources, (linked_item_t *) ds);
@@ -78,14 +80,14 @@ int posix_remove_data_source(data_source_t *ds){
 /**
  * Add timer to run_loop (keep list sorted)
  */
-void posix_add_timer(timer_source_t *ts){
+static void posix_add_timer(timer_source_t *ts){
     linked_item_t *it;
     for (it = (linked_item_t *) &timers; it->next ; it = it->next){
         if ((timer_source_t *) it->next == ts){
             log_error( "run_loop_timer_add error: timer to add already in list!\n");
             return;
         }
-        if (run_loop_timer_compare( (timer_source_t *) it->next, ts) > 0) {
+        if (posix_timer_compare( (timer_source_t *) it->next, ts) > 0) {
             break;
         }
     }
@@ -98,13 +100,13 @@ void posix_add_timer(timer_source_t *ts){
 /**
  * Remove timer from run loop
  */
-int posix_remove_timer(timer_source_t *ts){
+static int posix_remove_timer(timer_source_t *ts){
     // log_info("Removed timer %x at %u\n", (int) ts, (unsigned int) ts->timeout.tv_sec);
     // posix_dump_timer();
     return linked_list_remove(&timers, (linked_item_t *) ts);
 }
 
-void posix_dump_timer(void){
+static void posix_dump_timer(void){
     linked_item_t *it;
     int i = 0;
     for (it = (linked_item_t *) timers; it ; it = it->next){
@@ -116,7 +118,7 @@ void posix_dump_timer(void){
 /**
  * Execute run_loop
  */
-void posix_execute(void) {
+static void posix_execute(void) {
     fd_set descriptors;
     data_source_t *ds;
     timer_source_t       *ts;
@@ -190,7 +192,7 @@ void posix_execute(void) {
 }
 
 // set timer
-void run_loop_set_timer(timer_source_t *a, uint32_t timeout_in_ms){
+static void posix_set_timer(timer_source_t *a, uint32_t timeout_in_ms){
     gettimeofday(&a->timeout, NULL);
     a->timeout.tv_sec  +=  timeout_in_ms / 1000;
     a->timeout.tv_usec += (timeout_in_ms % 1000) * 1000;
@@ -202,7 +204,7 @@ void run_loop_set_timer(timer_source_t *a, uint32_t timeout_in_ms){
 
 // compare timers - NULL is assumed to be before the Big Bang
 // pre: 0 <= tv_usec < 1000000
-int run_loop_timeval_compare(struct timeval *a, struct timeval *b){
+static int posix_timeval_compare(struct timeval *a, struct timeval *b){
     if (!a && !b) return 0;
     if (!a) return -1;
     if (!b) return 1;
@@ -227,14 +229,14 @@ int run_loop_timeval_compare(struct timeval *a, struct timeval *b){
 
 // compare timers - NULL is assumed to be before the Big Bang
 // pre: 0 <= tv_usec < 1000000
-int run_loop_timer_compare(timer_source_t *a, timer_source_t *b){
+static int posix_timer_compare(timer_source_t *a, timer_source_t *b){
     if (!a && !b) return 0;
     if (!a) return -1;
     if (!b) return 1;
-    return run_loop_timeval_compare(&a->timeout, &b->timeout);
+    return posix_timeval_compare(&a->timeout, &b->timeout);
 }
 
-void posix_init(void){
+static void posix_init(void){
     data_sources = NULL;
     timers = NULL;
 }
@@ -243,8 +245,9 @@ run_loop_t run_loop_posix = {
     &posix_init,
     &posix_add_data_source,
     &posix_remove_data_source,
+    &posix_set_timer,
     &posix_add_timer,
     &posix_remove_timer,
     &posix_execute,
-    &posix_dump_timer
+    &posix_dump_timer,
 };
diff --git a/src/run_loop_private.h b/src/run_loop_private.h
index 61d382344..8a49b503c 100644
--- a/src/run_loop_private.h
+++ b/src/run_loop_private.h
@@ -52,12 +52,6 @@
 extern "C" {
 #endif
 
-#ifdef HAVE_TIME
-// compare timeval or timers - NULL is assumed to be before the Big Bang
-int run_loop_timeval_compare(struct timeval *a, struct timeval *b);
-int run_loop_timer_compare(timer_source_t *a, timer_source_t *b);
-#endif
-
 // 
 void run_loop_timer_dump(void);
 
@@ -66,6 +60,7 @@ typedef struct {
 	void (*init)(void);
 	void (*add_data_source)(data_source_t *dataSource);
 	int  (*remove_data_source)(data_source_t *dataSource);
+	void (*set_timer)(timer_source_t * timer, uint32_t timeout_in_ms);
 	void (*add_timer)(timer_source_t *timer);
 	int  (*remove_timer)(timer_source_t *timer); 
 	void (*execute)(void);