diff --git a/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py b/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py
index 85a55efc68..967f6103fb 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py
+++ b/libraries/AP_HAL_ChibiOS/hwdef/scripts/chibios_hwdef.py
@@ -3355,6 +3355,9 @@ INCLUDE common.ld
 // no crossfire telemetry from iomcu!
 #define HAL_CRSF_TELEM_ENABLED 0
 
+// allow the IOMCU to have its allowed protocols to be set:
+#define AP_RCPROTOCOL_ENABLE_SET_RC_PROTOCOLS 1
+
 // end IOMCU Firmware defaults
 ''')