diff --git a/libraries/AP_HAL_Linux/GPIO_Bebop.cpp b/libraries/AP_HAL_Linux/GPIO_Bebop.cpp
index 72060f5586..58f7cf6ca1 100644
--- a/libraries/AP_HAL_Linux/GPIO_Bebop.cpp
+++ b/libraries/AP_HAL_Linux/GPIO_Bebop.cpp
@@ -6,6 +6,7 @@
 
 const unsigned Linux::GPIO_Sysfs::pin_table[] = {
     [BEBOP_GPIO_CAMV_NRST] = 129,
+    [LINUX_GPIO_ULTRASOUND_VOLTAGE] = 200,
 };
 
 const uint8_t Linux::GPIO_Sysfs::n_pins = _BEBOP_GPIO_MAX;
diff --git a/libraries/AP_HAL_Linux/GPIO_Bebop.h b/libraries/AP_HAL_Linux/GPIO_Bebop.h
index fd5835dc72..157e319ebb 100644
--- a/libraries/AP_HAL_Linux/GPIO_Bebop.h
+++ b/libraries/AP_HAL_Linux/GPIO_Bebop.h
@@ -4,5 +4,6 @@
 
 enum gpio_bebop {
     BEBOP_GPIO_CAMV_NRST,
+    LINUX_GPIO_ULTRASOUND_VOLTAGE,
     _BEBOP_GPIO_MAX,
 };