From 1b1bc9f3b15dc881d1755298de4eb0e5f83eadcb Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Mon, 27 Jul 2015 10:05:33 +1000
Subject: [PATCH] RC_Channel: prevent floating exception on bad MIN/MAX/TRIM
 values

---
 libraries/RC_Channel/RC_Channel.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/libraries/RC_Channel/RC_Channel.cpp b/libraries/RC_Channel/RC_Channel.cpp
index 8f351758e5..2ec7b2e285 100644
--- a/libraries/RC_Channel/RC_Channel.cpp
+++ b/libraries/RC_Channel/RC_Channel.cpp
@@ -428,10 +428,16 @@ RC_Channel::norm_output()
 {
     int16_t mid = (radio_max + radio_min) / 2;
     float ret;
-    if(radio_out < mid)
+    if (mid <= radio_min) {
+        return 0;
+    }
+    if (radio_out < mid) {
         ret = (float)(radio_out - mid) / (float)(mid - radio_min);
-    else
+    } else if (radio_out > mid) {
         ret = (float)(radio_out - mid) / (float)(radio_max  - mid);
+    } else {
+        ret = 0;
+    }
     if (_reverse == -1) {
 	    ret = -ret;
     }