From 92fd45950497526c47980ab5eb713f11a48c9cb6 Mon Sep 17 00:00:00 2001
From: jphelirc <jphelirc@f9c3cf11-9bcb-44bc-f272-b75c42450872>
Date: Fri, 20 Aug 2010 16:41:41 +0000
Subject: [PATCH] adding missing sensors.pde file

git-svn-id: https://arducopter.googlecode.com/svn/trunk@251 f9c3cf11-9bcb-44bc-f272-b75c42450872
---
 Arducopter/Sensors.pde | 72 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)
 create mode 100644 Arducopter/Sensors.pde

diff --git a/Arducopter/Sensors.pde b/Arducopter/Sensors.pde
new file mode 100644
index 0000000000..20a5dd186b
--- /dev/null
+++ b/Arducopter/Sensors.pde
@@ -0,0 +1,72 @@
+/*
+ ArduCopter v1.3 - August 2010
+ www.ArduCopter.com
+ Copyright (c) 2010.  All rights reserved.
+ An Open Source Arduino based multicopter.
+ 
+ This program is free software: you can redistribute it and/or modify 
+ it under the terms of the GNU General Public License as published by 
+ the Free Software Foundation, either version 3 of the License, or 
+ (at your option) any later version. 
+ 
+ This program is distributed in the hope that it will be useful, 
+ but WITHOUT ANY WARRANTY; without even the implied warranty of 
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
+ GNU General Public License for more details. 
+ 
+ You should have received a copy of the GNU General Public License 
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+void ReadSCP1000(void) {
+}
+
+#ifdef UseBMP
+void read_airpressure(void){
+  double x;
+
+  APM_BMP085.Read(); 	//Get new data from absolute pressure sensor
+  abs_press = APM_BMP085.Press;
+  abs_press_filt = (abs_press); // + 2l * abs_press_filt) / 3l;		//Light filtering
+  //temperature = (temperature * 9 + temp_unfilt) / 10;    We will just use the ground temp for the altitude calculation	 
+
+  double p = (double)abs_press_gnd / (double)abs_press_filt;
+  double temp = (float)ground_temperature / 10.f + 273.15f;
+  x = log(p) * temp * 29271.267f;
+  //x = log(p) * temp * 29.271267 * 1000;
+  press_alt = (int)(x / 10) + ground_alt;		// Pressure altitude in centimeters
+  //  Need to add comments for theory.....
+}
+#endif
+
+#ifdef UseAirspeed
+void read_airspeed(void) {
+#if GCS_PROTOCOL != 3 // Xplane will supply the airspeed
+  airpressure_raw = ((float)analogRead(AIRSPEED_PIN) * .25) + (airpressure_raw * .75);
+  airpressure = (int)airpressure_raw - airpressure_offset;
+  airspeed = sqrt((float)airpressure / AIRSPEED_RATIO);
+#endif
+  airspeed_error = airspeed_cruise - airspeed;
+}
+#endif
+
+#if BATTERY_EVENT == 1
+void read_battery(void)
+{
+  battery_voltage = BATTERY_VOLTAGE(analogRead(BATTERY_PIN)) * .1 + battery_voltage * .9;
+  if(battery_voltage < LOW_VOLTAGE)
+    low_battery_event();
+}
+#endif
+
+#ifdef UseAirspeed
+void zero_airspeed(void)
+{
+  airpressure_raw = analogRead(AIRSPEED_PIN);
+  for(int c=0; c < 80; c++){
+    airpressure_raw = (airpressure_raw * .90) + ((float)analogRead(AIRSPEED_PIN) * .10);	
+  }
+  airpressure_offset = airpressure_raw;	
+}
+#endif
+