From d97c4d2f6de2981c2efd7bfbc9f5f9649987b854 Mon Sep 17 00:00:00 2001
From: Keith Packard <keithp@keithp.com>
Date: Tue, 9 May 2017 00:14:33 -0700
Subject: [PATCH] altoslib: Add AltosForce and AltosPressure units

Useful for TeleFireTwo.

Signed-off-by: Keith Packard <keithp@keithp.com>
---
 altoslib/AltosConvert.java  | 25 +++++++++++++++++++
 altoslib/AltosForce.java    | 49 ++++++++++++++++++++++++++++++++++++
 altoslib/AltosPressure.java | 50 +++++++++++++++++++++++++++++++++++++
 3 files changed, 124 insertions(+)
 create mode 100644 altoslib/AltosForce.java
 create mode 100644 altoslib/AltosPressure.java

diff --git a/altoslib/AltosConvert.java b/altoslib/AltosConvert.java
index 8617a12c..3489a609 100644
--- a/altoslib/AltosConvert.java
+++ b/altoslib/AltosConvert.java
@@ -21,6 +21,8 @@
  */
 package org.altusmetrum.altoslib_11;
 
+import java.util.*;
+
 public class AltosConvert {
 	/*
 	 * Pressure Sensor Model, version 1.1
@@ -370,12 +372,28 @@ public class AltosConvert {
 		return psi * 6894.76;
 	}
 
+	public static double pa_to_psi(double pa) {
+		return pa / 6894.76;
+	}
+
+	public static double n_to_lb(double n) {
+		return n * 0.22480894;
+	}
+
+	public static double lb_to_n(double lb) {
+		return lb / 0.22480894;
+	}
+
 	public static boolean imperial_units = false;
 
 	public static AltosDistance distance = new AltosDistance();
 
 	public static AltosHeight height = new AltosHeight();
 
+	public static AltosPressure pressure = new AltosPressure();
+
+	public static AltosForce force = new AltosForce();
+
 	public static AltosSpeed speed = new AltosSpeed();
 
 	public static AltosAccel accel = new AltosAccel();
@@ -407,6 +425,13 @@ public class AltosConvert {
 		return csum & 0xff;
 	}
 
+	public static int checksum(List<Byte> data, int start, int length) {
+		int	csum = 0x5a;
+		for (int i = 0; i < length; i++)
+			csum += data.get(i+start);
+		return csum & 0xff;
+	}
+
 	public static double beep_value_to_freq(int value) {
 		if (value == 0)
 			return 4000;
diff --git a/altoslib/AltosForce.java b/altoslib/AltosForce.java
new file mode 100644
index 00000000..229d04f3
--- /dev/null
+++ b/altoslib/AltosForce.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright © 2017 Keith Packard <keithp@keithp.com>
+ *
+ * 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; version 2 of the License.
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+package org.altusmetrum.altoslib_11;
+
+public class AltosForce extends AltosUnits {
+
+	public double value(double v, boolean imperial_units) {
+		if (imperial_units)
+			return AltosConvert.n_to_lb(v);
+		return v;
+	}
+
+	public double inverse(double v, boolean imperial_units) {
+		if (imperial_units)
+			return AltosConvert.lb_to_n(v);
+		return v;
+	}
+
+	public String show_units(boolean imperial_units) {
+		if (imperial_units)
+			return "lbs";
+		return "N";
+	}
+
+	public String say_units(boolean imperial_units) {
+		if (imperial_units)
+			return "pounds";
+		return "newtons";
+	}
+
+	public int show_fraction(int width, boolean imperial_units) {
+		return width / 9;
+	}
+}
diff --git a/altoslib/AltosPressure.java b/altoslib/AltosPressure.java
new file mode 100644
index 00000000..2de26820
--- /dev/null
+++ b/altoslib/AltosPressure.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright © 2017 Keith Packard <keithp@keithp.com>
+ *
+ * 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 2 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+package org.altusmetrum.altoslib_11;
+
+public class AltosPressure extends AltosUnits {
+
+	public double value(double v, boolean imperial_units) {
+		if (imperial_units)
+			return AltosConvert.pa_to_psi(v);
+		return v;
+	}
+
+	public double inverse(double v, boolean imperial_units) {
+		if (imperial_units)
+			return AltosConvert.psi_to_pa(v);
+		return v;
+	}
+
+	public String show_units(boolean imperial_units) {
+		if (imperial_units)
+			return "psi";
+		return "Pa";
+	}
+
+	public String say_units(boolean imperial_units) {
+		if (imperial_units)
+			return "p s i";
+		return "pascals";
+	}
+
+	public int show_fraction(int width, boolean imperial_units) {
+		return width / 9;
+	}
+}
-- 
2.30.2