diff --git a/docs/pinout_extension_port.txt b/docs/pinout_extension_port.txt
new file mode 100644
index 0000000..11306bb
--- /dev/null
+++ b/docs/pinout_extension_port.txt
@@ -0,0 +1,26 @@
+Created by DF8OE
+----------------
+
+
+
+view into port from outside
+
+
+______________________|           |______________________
+|                                                       |
+|   1           2           3           4           5   |
+|                                                       |
+|   6           7           8           9          10   |
+|_______________________________________________________|
+
+
+ 1 - SWDIO (PA13)
+ 2 - RST
+ 3 - MCU switched 3.3V out to external device
+ 4 - I2C2_SCL (PB10)
+ 5 - GND
+ 6 - GND
+ 7 - SWCLK (PA14)
+ 8 - +U_Battery
+ 9 - +VDD_MCU
+10 - I2C2_SDA (PB11)
\ No newline at end of file
diff --git a/main.c b/main.c
index 34c1fe8..a620cab 100644
--- a/main.c
+++ b/main.c
@@ -67,10 +67,14 @@ void USART1_IRQHandler(void) {
 void TIM2_IRQHandler(void) {
   if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) {
     TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
+
+    if (aprs_is_active()){
+      aprs_timer_handler();
+    } else {
       if (ALLOW_DISABLE_BY_BUTTON){
-        if (ADCVal[1] > adc_bottom * 1.1){
+        if (ADCVal[1] > adc_bottom){
           button_pressed++;
-          if (button_pressed > (5 * RTTY_SPEED)){
+          if (button_pressed > (RTTY_SPEED / 3)){
             disable_armed = 1;
             GPIO_SetBits(GPIOB, RED);
             GPIO_SetBits(GPIOB, GREEN);
@@ -82,13 +86,9 @@ void TIM2_IRQHandler(void) {
           button_pressed = 0;
         }
     	if (button_pressed == 0) {
-    	  adc_bottom = ADCVal[1];	// dynamical reference for power down level
+    	  adc_bottom = ADCVal[1] * 1.1;	// dynamical reference for power down level
 		}
       }
-
-    if (aprs_is_active()){
-      aprs_timer_handler();
-    } else {
       if (tx_on) {
         send_rtty_status = send_rtty((char *) rtty_buf);
         if (!disable_armed){