diff --git a/ex_3/main.c b/ex_3/main.c
index 2ce49e56beb161fe6b7725dd0e557fe5591b0aae..9c153c1470a6e3c9e443b724c91af2ea10ce6347 100644
--- a/ex_3/main.c
+++ b/ex_3/main.c
@@ -94,12 +94,10 @@ uint32_t init_timers() {
 int main(void) {
     /* Configure board. */
     bsp_board_init(BSP_INIT_LEDS);
-    //init_timers();
+    init_timers();
     while(true) {
-      bsp_board_led_invert(0); // blink led1
-      nrf_delay_ms(500); // do a busy wait
-      //__WFE(); // sleep until an event wakes us up
-      //__SEV(); // sleep until an event wakes us up
-      //__WFE(); // sleep until an event wakes us up
+      __WFE(); // sleep until an event wakes us up
+      __SEV(); // sleep until an event wakes us up
+      __WFE(); // sleep until an event wakes us up
     }
 }
diff --git a/ex_3/pca10040/blank/config/sdk_config.h b/ex_3/pca10040/blank/config/sdk_config.h
index cfab48fda2ca2c4ef0b3d84ad81a09b7f73a054d..313db343809184131398709fca0324d3e0022a9f 100644
--- a/ex_3/pca10040/blank/config/sdk_config.h
+++ b/ex_3/pca10040/blank/config/sdk_config.h
@@ -3326,7 +3326,7 @@
 // <3=> 32 bit 
 
 #ifndef NRFX_TIMER_DEFAULT_CONFIG_BIT_WIDTH
-#define NRFX_TIMER_DEFAULT_CONFIG_BIT_WIDTH 0
+#define NRFX_TIMER_DEFAULT_CONFIG_BIT_WIDTH 3
 #endif
 
 // <o> NRFX_TIMER_DEFAULT_CONFIG_IRQ_PRIORITY  - Interrupt priority