From f58abb75502a362340c36624c93d6dec2a67beb7 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <tridge@samba.org>
Date: Mon, 5 Nov 2012 23:37:25 +1100
Subject: [PATCH] RC_Channel: added pwm_to_angle_dz() function

will be used by k_aileron in APM
---
 libraries/RC_Channel/RC_Channel.cpp | 22 +++++++++++++++++-----
 libraries/RC_Channel/RC_Channel.h   |  1 +
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/libraries/RC_Channel/RC_Channel.cpp b/libraries/RC_Channel/RC_Channel.cpp
index c505cd2fa3..8b086e876c 100644
--- a/libraries/RC_Channel/RC_Channel.cpp
+++ b/libraries/RC_Channel/RC_Channel.cpp
@@ -217,13 +217,15 @@ RC_Channel::update_min_max()
     radio_max = max(radio_max.get(), radio_in);
 }
 
-// ------------------------------------------
-
+/*
+  return an "angle in centidegrees" (normally -4500 to 4500) from
+  the current radio_in value using the specified dead_zone
+ */
 int16_t
-RC_Channel::pwm_to_angle()
+RC_Channel::pwm_to_angle_dz(int16_t dead_zone)
 {
-    int16_t radio_trim_high = radio_trim + _dead_zone;
-    int16_t radio_trim_low  = radio_trim - _dead_zone;
+    int16_t radio_trim_high = radio_trim + dead_zone;
+    int16_t radio_trim_low  = radio_trim - dead_zone;
 
     // prevent div by 0
     if ((radio_trim_low - radio_min) == 0 || (radio_max - radio_trim_high) == 0)
@@ -237,6 +239,16 @@ RC_Channel::pwm_to_angle()
         return 0;
 }
 
+/*
+  return an "angle in centidegrees" (normally -4500 to 4500) from
+  the current radio_in value
+ */
+int16_t
+RC_Channel::pwm_to_angle()
+{
+	return pwm_to_angle_dz(_dead_zone);
+}
+
 
 int16_t
 RC_Channel::angle_to_pwm()
diff --git a/libraries/RC_Channel/RC_Channel.h b/libraries/RC_Channel/RC_Channel.h
index a39ce86db8..61ead5027b 100644
--- a/libraries/RC_Channel/RC_Channel.h
+++ b/libraries/RC_Channel/RC_Channel.h
@@ -78,6 +78,7 @@ public:
     // includes offset from PWM
     //int16_t   get_radio_out(void);
 
+    int16_t                                         pwm_to_angle_dz(int16_t dead_zone);
     int16_t                                         pwm_to_angle();
     float                                           norm_input();
     float                                           norm_output();