diff --git a/libraries/AP_HAL_ChibiOS/hwdef/KakuteF4/hwdef.dat b/libraries/AP_HAL_ChibiOS/hwdef/KakuteF4/hwdef.dat
index 8e5ee112f6eb6..4a9e82c69a9b4 100644
--- a/libraries/AP_HAL_ChibiOS/hwdef/KakuteF4/hwdef.dat
+++ b/libraries/AP_HAL_ChibiOS/hwdef/KakuteF4/hwdef.dat
@@ -71,11 +71,11 @@ define HAL_BATT_CURR_SCALE 17.0
 SERIAL_ORDER OTG1 USART6 USART1 UART4 UART5 USART3
 
 # rcinput is PB11
-#PB11 TIM2_CH4 TIM2 RCININT PULLDOWN LOW
-
-# Testing UART3 for CRSF
+PB11 TIM2_CH4 TIM2 RCININT PULLDOWN LOW
 PB10 USART3_TX USART3
-PB11 USART3_RX USART3
+
+# alternative
+PB11 USART3_RX USART3 ALT(1)
 
 # SBUS inversion control pin, active high
 PB15 USART3_RXINV OUTPUT LOW GPIO(78) POL(0)