diff --git a/src/hal/ttgobeam.h b/src/hal/ttgobeam.h
index 6def5f10..e47baa4c 100644
--- a/src/hal/ttgobeam.h
+++ b/src/hal/ttgobeam.h
@@ -3,6 +3,7 @@
 #define CFG_sx1276_radio 1 // HPD13A LoRa SoC
 
 #define HAS_LED 21 // on board green LED_G1
+#define HAS_BUTTON GPIO_NUM_39 // button on board next to battery indicator LED (other one is reset)
 #define HAS_BATTERY_PROBE ADC1_GPIO35_CHANNEL // battery probe GPIO pin -> ADC1_CHANNEL_7
 #define BATT_FACTOR 2 // voltage divider 100k/100k on board
 // #define HAS_GPS // to be done