diff --git a/equeue_mbed.cpp b/equeue_mbed.cpp
index cf3004d..122910a 100644
--- a/equeue_mbed.cpp
+++ b/equeue_mbed.cpp
@@ -15,9 +15,11 @@
 
 // Ticker operations
 static bool equeue_tick_inited = false;
-static unsigned equeue_timer[(sizeof(Timer)+1) / sizeof(unsigned)];
-static unsigned equeue_ticker[(sizeof(Ticker)+1) / sizeof(unsigned)];
 static unsigned equeue_minutes = 0;
+static unsigned equeue_timer[
+        (sizeof(Timer)+sizeof(unsigned)-1)/sizeof(unsigned)];
+static unsigned equeue_ticker[
+        (sizeof(Ticker)+sizeof(unsigned)-1)/sizeof(unsigned)];
 
 static void equeue_tick_update() {
     reinterpret_cast<Timer*>(equeue_timer)->reset();
@@ -112,7 +114,7 @@ bool equeue_sema_wait(equeue_sema_t *s, int ms) {
 
     core_util_critical_section_enter();
     while (!*s) {
-        __WFI();
+        sleep();
         core_util_critical_section_exit();
         core_util_critical_section_enter();
     }