--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Discovery/Src/unit.c	Sat Apr 28 11:52:34 2018 +0200
@@ -0,0 +1,184 @@
+///////////////////////////////////////////////////////////////////////////////
+/// -*- coding: UTF-8 -*-
+///
+/// \file   Discovery/Src/unit.c
+/// \brief  input to meter/celsius or feet/farenheit
+/// \author heinrichs weikamp gmbh
+/// \date   24-Feb-2015
+///
+/// \details
+///
+/// $Id$
+///////////////////////////////////////////////////////////////////////////////
+/// \par Copyright (c) 2014-2018 Heinrichs Weikamp gmbh
+///
+///     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/>.
+//////////////////////////////////////////////////////////////////////////////
+
+/* Includes ------------------------------------------------------------------*/
+#include "unit.h"
+#include "settings.h"
+
+/* Exported variables --------------------------------------------------------*/
+
+/* Private types -------------------------------------------------------------*/
+uint8_t  test;
+
+/* Private variables ---------------------------------------------------------*/
+
+/* Private variables with external access via get_xxx() function -------------*/
+
+/* Private function prototypes -----------------------------------------------*/
+
+/* Announced function prototypes -----------------------------------------------*/
+
+/* Exported functions --------------------------------------------------------*/
+
+char unit_depth_char1_T105(void)
+{
+    if(settingsGetPointer()->nonMetricalSystem)
+        return '\'';
+    else
+        return 'm';
+}
+
+char unit_depth_char2_T105(void)
+{
+    if(settingsGetPointer()->nonMetricalSystem)
+        return ' ';
+    else
+        return '\004'; // 004 is nop
+}
+
+char unit_depth_char1(void)
+{
+    if(settingsGetPointer()->nonMetricalSystem)
+        return 'f';
+    else
+        return 'm';
+}
+
+char unit_depth_char2(void)
+{
+    if(settingsGetPointer()->nonMetricalSystem)
+        return 't';
+    else
+        return '\004'; // 004 is nop
+}
+
+float unit_depth_float(float input_meter)
+{
+    if(settingsGetPointer()->nonMetricalSystem == 0)
+        return input_meter;
+    else
+    {
+        return 3.2808f * input_meter;
+    }
+}
+
+uint16_t unit_depth_integer(uint16_t input_meter)
+{
+    if(settingsGetPointer()->nonMetricalSystem == 0)
+        return input_meter;
+    else
+    {
+        return (input_meter * 10) / 3;
+    }
+}
+
+float unit_temperature_float(float input_celsius)
+{
+    if(settingsGetPointer()->nonMetricalSystem == 0)
+        return input_celsius;
+    else
+    {
+        return input_celsius * (9.0f/5.0f) + 32;
+    }
+}
+
+uint16_t unit_speed_integer(uint16_t input_meterPerMinute)
+{
+    if(settingsGetPointer()->nonMetricalSystem == 0)
+        return input_meterPerMinute;
+    else
+    {
+        return (input_meterPerMinute * 10) / 3;
+    }
+}
+
+/* Quelle: https://de.wikipedia.org/wiki/Luftdruck */
+/*
+const float luftdruckStartMinus300[15] =
+{
+    1.0530f,
+    1.0396f,
+    1.0263f,
+    1.01325f, // 0 m
+    1.0003f,
+    0.9876f,
+    0.9750f,
+    0.9625f,
+    0.9503f,
+    0.9381f,
+    0.9262f,
+    0.9144f,
+    0.9027f,
+    0.8912f, // 1000 m
+    0.8358f
+};
+*/
+
+const int luftdruckStartMinus300[15] =
+{
+    1053,
+    1040,
+    1026,
+    1013, // 0 m
+    1000,
+     988,
+     975,
+     962,
+     950,
+     938,
+     926,
+     914,
+     903,
+     891, // 1000 m
+     836
+};
+
+
+int unit_SeaLevelRelation_integer(int input_atmospheric_mbar)
+{
+    int i = 0;
+    int distance1, distance2;
+    for(i=0;i<15;i++)
+    {
+        if(input_atmospheric_mbar >= luftdruckStartMinus300[i])
+            break;
+    }
+
+    if(i >= 14)
+        return 1500;
+    else if(i == 0)
+        return -300;
+    else
+    {
+        distance1 = input_atmospheric_mbar - luftdruckStartMinus300[i];
+        distance2 = luftdruckStartMinus300[i-1] - input_atmospheric_mbar;
+        if(distance2 < distance1)
+            i -= 1;
+        return (i*100) - 300;
+    }
+}