diff --git a/nucleo-wb55-ble/Core/Inc/stm32wbxx_it.h b/nucleo-wb55-ble/Core/Inc/stm32wbxx_it.h
index b01d95d..e06a700 100644
--- a/nucleo-wb55-ble/Core/Inc/stm32wbxx_it.h
+++ b/nucleo-wb55-ble/Core/Inc/stm32wbxx_it.h
@@ -56,7 +56,6 @@ void SVC_Handler(void);
 void DebugMon_Handler(void);
 void PendSV_Handler(void);
 void SysTick_Handler(void);
-void EXTI4_IRQHandler(void);
 void USB_LP_IRQHandler(void);
 void HSEM_IRQHandler(void);
 /* USER CODE BEGIN EFP */
diff --git a/nucleo-wb55-ble/Core/Src/app_entry.c b/nucleo-wb55-ble/Core/Src/app_entry.c
index 87611f9..f77eed4 100644
--- a/nucleo-wb55-ble/Core/Src/app_entry.c
+++ b/nucleo-wb55-ble/Core/Src/app_entry.c
@@ -96,15 +96,6 @@ void APPE_Init( void )
    return;
 }
 /* USER CODE BEGIN FD */
-void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin) {
-	switch (GPIO_Pin) {
-		case SW1_Pin:
-			UTIL_SEQ_SetTask(1<<CFG_TASK_SW1_BUTTON_PUSHED_ID, CFG_SCH_PRIO_0);
-			break;
-		default:
-			break;
-	}
-}
 
 /* USER CODE END FD */
 
diff --git a/nucleo-wb55-ble/Core/Src/stm32wbxx_it.c b/nucleo-wb55-ble/Core/Src/stm32wbxx_it.c
index 8a290fd..8c1e231 100644
--- a/nucleo-wb55-ble/Core/Src/stm32wbxx_it.c
+++ b/nucleo-wb55-ble/Core/Src/stm32wbxx_it.c
@@ -200,20 +200,6 @@ void SysTick_Handler(void)
 /* please refer to the startup file (startup_stm32wbxx.s).                    */
 /******************************************************************************/
 
-/**
-  * @brief This function handles EXTI line4 interrupt.
-  */
-void EXTI4_IRQHandler(void)
-{
-  /* USER CODE BEGIN EXTI4_IRQn 0 */
-
-  /* USER CODE END EXTI4_IRQn 0 */
-  HAL_GPIO_EXTI_IRQHandler(GPIO_PIN_4);
-  /* USER CODE BEGIN EXTI4_IRQn 1 */
-
-  /* USER CODE END EXTI4_IRQn 1 */
-}
-
 /**
   * @brief This function handles USB low priority interrupt, USB wake-up interrupt through EXTI line 28.
   */
diff --git a/nucleo-wb55-ble/STM32_WPAN/App/p2p_server_app.c b/nucleo-wb55-ble/STM32_WPAN/App/p2p_server_app.c
index 967aec9..1b3c044 100644
--- a/nucleo-wb55-ble/STM32_WPAN/App/p2p_server_app.c
+++ b/nucleo-wb55-ble/STM32_WPAN/App/p2p_server_app.c
@@ -139,7 +139,7 @@ void P2PS_APP_Notification(P2PS_APP_ConnHandle_Not_evt_t *pNotification)
 void P2PS_APP_Init(void)
 {
 /* USER CODE BEGIN P2PS_APP_Init */
-	UTIL_SEQ_RegTask(CFG_TASK_SW1_BUTTON_PUSHED_ID, UTIL_SEQ_DEFAULT, P2PS_Send_Notification);
+	UTIL_SEQ_RegTask(1<< CFG_TASK_SW1_BUTTON_PUSHED_ID, UTIL_SEQ_DEFAULT, P2PS_Send_Notification);
 /* USER CODE END P2PS_APP_Init */
   return;
 }
diff --git a/nucleo-wb55-ble/commands/GPCommand.cpp b/nucleo-wb55-ble/commands/GPCommand.cpp
new file mode 100644
index 0000000..daa94d4
--- /dev/null
+++ b/nucleo-wb55-ble/commands/GPCommand.cpp
@@ -0,0 +1,50 @@
+/*
+ * GPCommand.cpp
+ *
+ *  Created on: Jul 18, 2021
+ *      Author: Andreas Berthoud
+ */
+
+#include "GPCommand.hpp"
+
+#include "app_conf.h"
+#include "stm32_seq.h"
+
+
+GPResponse::GPResponse(uint16_t response_identifier, bool was_successful)
+  : Response(response_identifier) {
+  (this->payload_ptr + this->get_payload_size())[0] = (uint8_t)was_successful;
+  this->add_to_payload_size(1);
+}
+
+GPRequest::GPRequest(uint8_t * payload_ptr, uint16_t size) : Request(payload_ptr, size) {
+  uint16_t expected_length = this->buffer_offset + 1;
+  if (expected_length != size) {
+    this->has_error = true;
+    return;
+  }
+
+  uint8_t * data_ptr = payload_ptr + this->buffer_offset;
+  this->command_id = data_ptr[0];
+}
+
+GPResponse * GPRequest::execute_request(uint16_t response_identifier) {
+  bool was_successful = true;
+
+  if (this->has_error) {
+    was_successful = false;
+  } else {
+    switch (this->command_id)
+    {
+    case 1:
+      UTIL_SEQ_SetTask(1<<CFG_TASK_SW1_BUTTON_PUSHED_ID, CFG_SCH_PRIO_0);
+      break;
+
+    default:
+      break;
+    }
+  }
+
+  return new GPResponse(response_identifier, was_successful);
+}
+
diff --git a/nucleo-wb55-ble/commands/GPCommand.hpp b/nucleo-wb55-ble/commands/GPCommand.hpp
new file mode 100644
index 0000000..ef87bf2
--- /dev/null
+++ b/nucleo-wb55-ble/commands/GPCommand.hpp
@@ -0,0 +1,47 @@
+/*
+ * GPCommand.hpp
+ *
+ *  Created on: Jul 18, 2021
+ *      Author: Andreas Berthoud
+ */
+
+#ifndef GPCOMMAND_HPP_
+#define GPCOMMAND_HPP_
+
+#include "Request.hpp"
+#include "Response.hpp"
+
+class GPResponse : public Response {
+public:
+  GPResponse(uint16_t response_identifier, bool was_successful);
+
+  CommandId get_command_id() override { return COMMAND_GP_RESPONSE; }
+
+private:
+  bool was_successful = false;
+};
+
+class GPRequest : public Request {
+public:
+  /**
+   * @brief Construct a new general purpose request object
+   *
+   * @param payload_ptr
+   *    HEADER | command_id |
+   *           | 1 byte     |
+   *
+   * @param size
+   */
+  GPRequest(uint8_t * payload_ptr, uint16_t size);
+
+
+  GPResponse * execute_request(uint16_t response_identifier);
+
+  CommandId get_command_id() override { return COMMAND_GP_REQUEST; }
+
+private:
+  bool has_error = false;
+  int command_id = 0;
+};
+
+#endif /* GPCOMMAND_HPP_ */
diff --git a/nucleo-wb55-ble/commands/dispatch.cpp b/nucleo-wb55-ble/commands/dispatch.cpp
index 2dfcd16..95c4c0e 100644
--- a/nucleo-wb55-ble/commands/dispatch.cpp
+++ b/nucleo-wb55-ble/commands/dispatch.cpp
@@ -9,6 +9,7 @@
 
 #include "HeartbeatCommand.hpp"
 #include "LedCommand.hpp"
+#include "GPCommand.hpp"
 
 void handle_received_command(uint8_t command_id, uint8_t * payload_ptr, uint16_t size) {
 
@@ -20,6 +21,9 @@ void handle_received_command(uint8_t command_id, uint8_t * payload_ptr, uint16_t
   case COMMAND_LED_REQUEST:
     push_command(new LedRequest(payload_ptr, size));
     break;
+  case COMMAND_GP_REQUEST:
+    push_command(new GPRequest(payload_ptr, size));
+    break;
 
   default:
     break;
diff --git a/nucleo-wb55-dongle-ble/STM32_WPAN/App/p2p_client_app.c b/nucleo-wb55-dongle-ble/STM32_WPAN/App/p2p_client_app.c
index e3e60e8..035f436 100644
--- a/nucleo-wb55-dongle-ble/STM32_WPAN/App/p2p_client_app.c
+++ b/nucleo-wb55-dongle-ble/STM32_WPAN/App/p2p_client_app.c
@@ -568,6 +568,8 @@ void Gatt_Notification(P2P_Client_App_Notification_evt_t *pNotification)
 {
 /* USER CODE BEGIN Gatt_Notification_1*/
   log_debug("Gatt_Notification", "enter", 0);
+  log_debug("Gatt_Notification", "pNotification->P2P_Client_Evt_Opcode=0x%x", 1, pNotification->P2P_Client_Evt_Opcode);
+
 
 /* USER CODE END Gatt_Notification_1 */
   switch(pNotification->P2P_Client_Evt_Opcode)
@@ -580,6 +582,8 @@ void Gatt_Notification(P2P_Client_App_Notification_evt_t *pNotification)
 /* USER CODE BEGIN P2P_NOTIFICATION_INFO_RECEIVED_EVT */
     {
       P2P_Client_App_Context.LedControl.Device_Led_Selection=pNotification->DataTransfered.pPayload[0];
+      log_debug("Gatt_Notification", "DataTransfered.pPayload[0]=0x%x", 1, pNotification->DataTransfered.pPayload[0]);
+      log_debug("Gatt_Notification", "DataTransfered.pPayload[1]=0x%x", 1, pNotification->DataTransfered.pPayload[1]);
       switch(P2P_Client_App_Context.LedControl.Device_Led_Selection) {
 
         case 0x01 : {