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diff --git a/usb-bmp180/usb-bmp180.c b/usb-bmp180/usb-bmp180.c
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+/*
+ *  spreadspace avr utils - usb-bmp180 example
+ *
+ *
+ *  Copyright (C) 2016 Bernhard Tittelbach <bernhard@tittelbach.org>
+ *  basically this is refactored and enhanced code from:
+ *   https://github.com/sparkfun/BMP180_Breakout_Arduino_Library
+ *   Please buy the sparkfun people Beer when you see them!!!!
+ *
+ *  This file is part of spreadspace avr utils.
+ *
+ *  spreadspace avr utils 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
+ *  any later version.
+ *
+ *  spreadspace avr utils 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 spreadspace avr utils. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <avr/io.h>
+#include <avr/wdt.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include <stdio.h>
+
+#include "util.h"
+#include "led.h"
+#include "usbio.h"
+
+#include "Arduino.h"
+#include "SFE_BMP180.h"
+
+
+SFE_BMP180 pressure;
+
+#define ALTITUDE 353.0 // Altitude of Graz in Austria
+
+
+int main(void)
+{
+  MCUSR &= ~(1 << WDRF);
+  wdt_disable();
+
+  cpu_init();
+  led_init();
+  usbio_init();
+  sei();
+
+  arduino_init();
+
+  if (pressure.begin())
+    printf("BMP180 init success");
+  else
+  {
+    // Oops, something went wrong, this is usually a connection problem,
+    // see the comments at the top of this sketch for the proper connections.
+
+    printf("BMP180 init fail\n\n");
+    while(1); // Pause forever.
+  }
+
+  for(;;) {
+    usbio_task();
+
+    char status;
+    double T,P,p0,a;
+
+    // Loop here getting pressure readings every 10 seconds.
+
+    // If you want sea-level-compensated pressure, as used in weather reports,
+    // you will need to know the altitude at which your measurements are taken.
+    // We're using a constant called ALTITUDE in this sketch:
+    
+    printf("\nprovided altitude: ");
+    printf(ALTITUDE,0);
+    printf(" meters, ");
+    printf(ALTITUDE*3.28084,0);
+    printf(" feet\n");
+    
+    // If you want to measure altitude, and not pressure, you will instead need
+    // to provide a known baseline pressure. This is shown at the end of the sketch.
+
+    // You must first get a temperature measurement to perform a pressure reading.
+    
+    // Start a temperature measurement:
+    // If request is successful, the number of ms to wait is returned.
+    // If request is unsuccessful, 0 is returned.
+
+    status = pressure.startTemperature();
+    if (status != 0)
+    {
+      // Wait for the measurement to complete:
+      _delay_ms(status);
+
+      // Retrieve the completed temperature measurement:
+      // Note that the measurement is stored in the variable T.
+      // Function returns 1 if successful, 0 if failure.
+
+      status = pressure.getTemperature(T);
+      if (status != 0)
+      {
+        // Print out the measurement:
+        printf("temperature: %02d degC\n",T);
+        
+        // Start a pressure measurement:
+        // The parameter is the oversampling setting, from 0 to 3 (highest res, longest wait).
+        // If request is successful, the number of ms to wait is returned.
+        // If request is unsuccessful, 0 is returned.
+
+        status = pressure.startPressure(3);
+        if (status != 0)
+        {
+          // Wait for the measurement to complete:
+          _delay_ms(status);
+
+          // Retrieve the completed pressure measurement:
+          // Note that the measurement is stored in the variable P.
+          // Note also that the function requires the previous temperature measurement (T).
+          // (If temperature is stable, you can do one temperature measurement for a number of pressure measurements.)
+          // Function returns 1 if successful, 0 if failure.
+
+          status = pressure.getPressure(P,T);
+          if (status != 0)
+          {
+            // Print out the measurement:
+            printf("absolute pressure: %02d mb, %02d inHg\n", P, P*0.0295333727);
+
+            // The pressure sensor returns abolute pressure, which varies with altitude.
+            // To remove the effects of altitude, use the sealevel function and your current altitude.
+            // This number is commonly used in weather reports.
+            // Parameters: P = absolute pressure in mb, ALTITUDE = current altitude in m.
+            // Result: p0 = sea-level compensated pressure in mb
+
+            p0 = pressure.sealevel(P,ALTITUDE); // we're at 1655 meters (Boulder, CO)
+            printf("relative (sea-level) pressure: %02d mb, %0d2 inHg", p0, p0*0.0295333727);
+
+            // On the other hand, if you want to determine your altitude from the pressure reading,
+            // use the altitude function along with a baseline pressure (sea-level or other).
+            // Parameters: P = absolute pressure in mb, p0 = baseline pressure in mb.
+            // Result: a = altitude in m.
+
+            a = pressure.altitude(P,p0);
+            printf("computed altitude: %dm\n",a);
+          }
+          else printf("error retrieving pressure measurement\n");
+        }
+        else printf("error starting pressure measurement\n");
+      }
+      else printf("error retrieving temperature measurement\n");
+    }
+    else printf("error starting temperature measurement\n");
+
+    _delay_ms(5000);  // Pause for 5 seconds.
+
+  }
+}