diff --git a/cube/User/Inc/loopCtrl.h b/cube/User/Inc/loopCtrl.h
index 3ea1653..894bf6e 100644
--- a/cube/User/Inc/loopCtrl.h
+++ b/cube/User/Inc/loopCtrl.h
@@ -1,8 +1,13 @@
 #ifndef _LOOPCTRL_H_
 #define _LOOPCTRL_H_
 
+#include <stdbool.h>
+
 void loopEnable();
 void loopDisable();
+void loopStatusCallback();
+
+extern bool loopActive;
 
 
 #endif // _LOOPCTRL_H_
diff --git a/cube/User/Src/loopCtrl.c b/cube/User/Src/loopCtrl.c
index 1242f4a..c597680 100644
--- a/cube/User/Src/loopCtrl.c
+++ b/cube/User/Src/loopCtrl.c
@@ -1,7 +1,12 @@
 #include <main.h>
 #include <loopCtrl.h>
+#include <led.h>
+
+
+bool loopActive = false;
 
 void loopEnable() {
+    loopActive = true;
     HAL_GPIO_WritePin(Loop_Enable_GPIO_Port, Loop_Enable_Pin, GPIO_PIN_SET);
     HAL_GPIO_WritePin(Loop_Enable_GPIO_Port, Loop_Enable_Pin, GPIO_PIN_RESET);
 }
@@ -9,4 +14,13 @@ void loopEnable() {
 void loopDisable() {
     HAL_GPIO_WritePin(Loop_Disable_GPIO_Port, Loop_Disable_Pin, GPIO_PIN_SET);
     HAL_GPIO_WritePin(Loop_Disable_GPIO_Port, Loop_Disable_Pin, GPIO_PIN_RESET);
+    loopActive = false;
 }
+
+void loopStatusCallback() {
+    GPIO_PinState status = HAL_GPIO_ReadPin(Loop_Status_GPIO_Port, Loop_Status_Pin);
+    if (status == GPIO_PIN_SET) {
+        ledRed(true);
+        loopActive = false;
+    }
+}
\ No newline at end of file
diff --git a/cube/User/Src/main2.c b/cube/User/Src/main2.c
index 9baf0f4..dbc2e1e 100644
--- a/cube/User/Src/main2.c
+++ b/cube/User/Src/main2.c
@@ -39,6 +39,11 @@ void helloWorld(void *handle) {
 
 void helloMeterbus(void *handle) {
     static char hello[] = "Hello Meterbus\n\r";
+    if (! loopActive) {
+        loopEnable();
+        ledRed(false);
+    }
+
     HAL_UART_Transmit_IT(&mbusUart, (uint8_t*) hello, strlen(hello));
 }
 
@@ -48,6 +53,7 @@ void toggleLoop(void *handle) {
     if (state) {
         loopDisable();
     } else {
+        ledRed(false);
         loopEnable();
     }
     state ^= true;
@@ -58,8 +64,8 @@ void my_setup_2() {
     ledGreen(true);
 
     schAdd(helloWorld, NULL, 0, 5000);
-    schAdd(toggleLoop, NULL, 0, 10000);
-    schAdd(helloMeterbus, NULL, 0, 1000);
+    // schAdd(toggleLoop, NULL, 0, 10000);
+    schAdd(helloMeterbus, NULL, 0, 10000);
 
 }
 
@@ -70,3 +76,9 @@ void my_loop() {
 void SYSTICK_Callback() {
     schUpdate();
 }
+
+void HAL_GPIO_EXTI_Callback(uint16_t pin) {
+    if (pin == Loop_Status_Pin) {
+        loopStatusCallback();
+    }
+}
\ No newline at end of file