From: Keith Packard <keithp@keithp.com>
Date: Thu, 3 Apr 2014 05:04:18 +0000 (-0700)
Subject: altoslib: Fix EasyMini voltage computations
X-Git-Tag: 1.3.2.2~157
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=21d584b9bf93b96a05ab374105493c0e17df320f;ds=sidebyside

altoslib: Fix EasyMini voltage computations

Early Em prototypes had a 3.0V regulator.
Early v1.0 boards measured power past the blocking diode.

Deal with both conditions to try and report more accurate voltages for
EasyMini data.

Signed-off-by: Keith Packard <keithp@keithp.com>
---

diff --git a/altoslib/AltosConvert.java b/altoslib/AltosConvert.java
index 8f214c8b..35923ec3 100644
--- a/altoslib/AltosConvert.java
+++ b/altoslib/AltosConvert.java
@@ -224,10 +224,21 @@ public class AltosConvert {
 		return sensor / 32767.0 * supply * 127/27;
 	}
 
-	static double easy_mini_voltage(int sensor) {
-		double	supply = 3.0;
+	static double easy_mini_voltage(int sensor, int serial) {
+		double	supply = 3.3;
+		double	diode_offset = 0.0;
 
-		return sensor / 32767.0 * supply * 127/27;
+		/* early prototypes had a 3.0V regulator */
+		if (serial < 1000)
+			supply = 3.0;
+
+		/* Purple v1.0 boards had the sensor after the
+		 * blocking diode, which drops about 150mV
+		 */
+		if (serial < 1665)
+			diode_offset = 0.150;
+
+		return sensor / 32767.0 * supply * 127/27 + diode_offset;
 	}
 
 	public static double radio_to_frequency(int freq, int setting, int cal, int channel) {
diff --git a/altoslib/AltosSensorEMini.java b/altoslib/AltosSensorEMini.java
index f888754c..5f43b3a9 100644
--- a/altoslib/AltosSensorEMini.java
+++ b/altoslib/AltosSensorEMini.java
@@ -31,10 +31,10 @@ public class AltosSensorEMini {
 
 			if (sensor_emini == null)
 				return;
-			state.set_battery_voltage(AltosConvert.easy_mini_voltage(sensor_emini.batt));
-			state.set_apogee_voltage(AltosConvert.easy_mini_voltage(sensor_emini.apogee));
-			state.set_main_voltage(AltosConvert.easy_mini_voltage(sensor_emini.main));
-			
+			state.set_battery_voltage(AltosConvert.easy_mini_voltage(sensor_emini.batt, config_data.serial));
+			state.set_apogee_voltage(AltosConvert.easy_mini_voltage(sensor_emini.apogee, config_data.serial));
+			state.set_main_voltage(AltosConvert.easy_mini_voltage(sensor_emini.main, config_data.serial));
+
 		} catch (TimeoutException te) {
 		}
 	}