diff --git a/Tools/AP_Periph/rc_out.cpp b/Tools/AP_Periph/rc_out.cpp
index 6b21058f64..3e697c9e7f 100644
--- a/Tools/AP_Periph/rc_out.cpp
+++ b/Tools/AP_Periph/rc_out.cpp
@@ -21,7 +21,7 @@
 // Raw ESC command normalized into [-8192, 8191]
 #define UAVCAN_ESC_MAX_VALUE    8191
 
-#define SERVO_OUT_RCIN_MAX      16  // SRV_Channel::k_rcin1 ... SRV_Channel::k_rcin16
+#define SERVO_OUT_RCIN_MAX      32  // note that we allow for more than is in the enum
 #define SERVO_OUT_MOTOR_MAX     12  // SRV_Channel::k_motor1 ... SRV_Channel::k_motor8, SRV_Channel::k_motor9 ... SRV_Channel::k_motor12
 
 extern const AP_HAL::HAL &hal;