From cf0741f6fd534d539002897abfa8c25a3aac9293 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <tridge@samba.org>
Date: Mon, 25 Aug 2014 19:45:39 +1000
Subject: [PATCH] Plane: don't do failsafe passthru with no RC input

thanks to Klrill-ka for the suggestion

fixes issue #1302
---
 ArduPlane/failsafe.pde | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/ArduPlane/failsafe.pde b/ArduPlane/failsafe.pde
index beb7acd7a0..3d96102707 100644
--- a/ArduPlane/failsafe.pde
+++ b/ArduPlane/failsafe.pde
@@ -37,8 +37,14 @@ void failsafe_check(void)
     }
 
     if (in_failsafe && tnow - last_timestamp > 20000) {
-        // pass RC inputs to outputs every 20ms
         last_timestamp = tnow;
+
+        if (hal.rcin->num_channels() == 0) {
+            // we don't have any RC input to pass through
+            return;
+        }
+
+        // pass RC inputs to outputs every 20ms
         hal.rcin->clear_overrides();
         channel_roll->radio_out     = channel_roll->read();
         channel_pitch->radio_out    = channel_pitch->read();