diff --git a/sw/airborne/arch/stm32/sys_time_hw.h b/sw/airborne/arch/stm32/sys_time_hw.h
index 9d88a69d8c..6b8e09fb83 100644
--- a/sw/airborne/arch/stm32/sys_time_hw.h
+++ b/sw/airborne/arch/stm32/sys_time_hw.h
@@ -50,6 +50,12 @@ extern uint32_t cpu_time_ticks;
 #define SYS_TICS_OF_SEC(s)        (uint32_t)((s) * AHB_CLK + 0.5)
 #define SIGNED_SYS_TICS_OF_SEC(s)  (int32_t)((s) * AHB_CLK + 0.5)
 
+/* Generic timer macros */
+//FIXME: untested!
+#define SysTimeTimerStart(_t) { _t = cpu_time_ticks; }
+#define SysTimeTimer(_t) ((uint32_t)(cpu_time_ticks - _t))
+#define SysTimeTimerStop(_t) { _t = (cpu_time_ticks - _t); }
+
 static inline bool_t sys_time_periodic( void ) {
   if (sys_time_period_elapsed) {
     sys_time_period_elapsed = FALSE;