initial upload

examples/osd/arduino-climate/Adafruit_HTU21DF.cpp

@@ -0,0 +1,100 @@
+/*************************************************** 
+  This is a library for the HTU21DF Humidity & Temp Sensor
+
+  Designed specifically to work with the HTU21DF sensor from Adafruit
+  ----> https://www.adafruit.com/products/1899
+
+  These displays use I2C to communicate, 2 pins are required to  
+  interface
+  Adafruit invests time and resources providing this open source code, 
+  please support Adafruit and open-source hardware by purchasing 
+  products from Adafruit!
+
+  Written by Limor Fried/Ladyada for Adafruit Industries.  
+  BSD license, all text above must be included in any redistribution
+ ****************************************************/
+
+#include "Adafruit_HTU21DF.h"
+#if defined(__AVR__)
+#include <util/delay.h>
+#endif
+
+Adafruit_HTU21DF::Adafruit_HTU21DF() {
+}
+
+
+boolean Adafruit_HTU21DF::begin(void) {
+  Wire.begin();
+  
+  reset();
+
+  Wire.beginTransmission(HTU21DF_I2CADDR);
+  Wire.write(HTU21DF_READREG);
+  Wire.endTransmission();
+  Wire.requestFrom(HTU21DF_I2CADDR, 1);
+  return (Wire.read() == 0x2); // after reset should be 0x2
+}
+
+void Adafruit_HTU21DF::reset(void) {
+  Wire.beginTransmission(HTU21DF_I2CADDR);
+  Wire.write(HTU21DF_RESET);
+  Wire.endTransmission();
+  delay(15);
+}
+
+
+float Adafruit_HTU21DF::readTemperature(void) {
+  
+  // OK lets ready!
+  Wire.beginTransmission(HTU21DF_I2CADDR);
+  Wire.write(HTU21DF_READTEMP);
+  Wire.endTransmission();
+  
+  delay(60); // add delay between request and actual read!
+  
+  Wire.requestFrom(HTU21DF_I2CADDR, 3);
+  while (!Wire.available()) {}
+
+  uint16_t t = Wire.read();
+  t <<= 8;
+  t |= Wire.read();
+
+  uint8_t crc = Wire.read();
+
+  float temp = t;
+  temp *= 175.72;
+  temp /= 65536;
+  temp -= 46.85;
+
+  return temp;
+}
+  
+
+float Adafruit_HTU21DF::readHumidity(void) {
+  // OK lets ready!
+  Wire.beginTransmission(HTU21DF_I2CADDR);
+  Wire.write(HTU21DF_READHUM);
+  Wire.endTransmission();
+  
+  delay(50); // add delay between request and actual read!
+  
+  Wire.requestFrom(HTU21DF_I2CADDR, 3);
+  while (!Wire.available()) {}
+
+  uint16_t h = Wire.read();
+  h <<= 8;
+  h |= Wire.read();
+
+  uint8_t crc = Wire.read();
+
+  float hum = h;
+  hum *= 125;
+  hum /= 65536;
+  hum -= 6;
+
+  return hum;
+}
+
+
+
+/*********************************************************************/

examples/osd/arduino-climate/Adafruit_HTU21DF.h

@@ -0,0 +1,44 @@
+/*************************************************** 
+  This is a library for the HTU21D-F Humidity & Temp Sensor
+
+  Designed specifically to work with the HTU21D-F sensor from Adafruit
+  ----> https://www.adafruit.com/products/1899
+
+  These displays use I2C to communicate, 2 pins are required to  
+  interface
+  Adafruit invests time and resources providing this open source code, 
+  please support Adafruit and open-source hardware by purchasing 
+  products from Adafruit!
+
+  Written by Limor Fried/Ladyada for Adafruit Industries.  
+  BSD license, all text above must be included in any redistribution
+ ****************************************************/
+
+//#if (ARDUINO >= 100)
+ #include "Arduino.h"
+//#else
+// #include "WProgram.h"
+//#endif
+#include "Wire.h"
+
+#define HTU21DF_I2CADDR       0x40
+#define HTU21DF_READTEMP      0xE3
+#define HTU21DF_READHUM       0xE5
+#define HTU21DF_WRITEREG       0xE6
+#define HTU21DF_READREG       0xE7
+#define HTU21DF_RESET       0xFE
+
+
+
+class Adafruit_HTU21DF {
+ public:
+  Adafruit_HTU21DF();
+  boolean begin(void);
+  float readTemperature(void);
+  float readHumidity(void);
+  void reset(void);
+ private:
+  boolean readData(void);
+  float humidity, temp;
+};
+

examples/osd/arduino-climate/Makefile

@@ -0,0 +1,63 @@
+# Set this to the name of your sketch (without extension .pde)
+SKETCH=sketch
+EXE=arduino-example
+
+all: $(EXE)
+
+CONTIKI=../../../../osd-contiki
+
+# Contiki IPv6 configuration
+CONTIKI_WITH_IPV6 = 1
+
+CFLAGS += -DPROJECT_CONF_H=\"project-conf.h\"
+LFLAGS += -lm
+
+PROJECT_SOURCEFILES += ${SKETCH}.cpp Adafruit_HTU21DF.cpp
+
+# automatically build RESTful resources
+REST_RESOURCES_DIR = ./resources
+REST_RESOURCES_DIR_COMMON = $(CONTIKI)/examples/osd/resources-common
+REST_RESOURCES_FILES= $(notdir \
+    $(shell find $(REST_RESOURCES_DIR) -name '*.c') \
+    $(shell find $(REST_RESOURCES_DIR_COMMON) -name '*.c') \
+    )
+
+PROJECTDIRS += $(REST_RESOURCES_DIR) $(REST_RESOURCES_DIR_COMMON)
+PROJECT_SOURCEFILES += $(REST_RESOURCES_FILES)
+# variable for Makefile.include
+ifneq ($(TARGET), minimal-net)
+CFLAGS += -DUIP_CONF_IPV6_RPL=1
+else
+# minimal-net does not support RPL under Linux and is mostly used to test CoAP only
+${info INFO: compiling without RPL}
+CFLAGS += -DUIP_CONF_IPV6_RPL=0
+CFLAGS += -DHARD_CODED_ADDRESS=\"fdfd::10\"
+${info INFO: compiling with large buffers}
+CFLAGS += -DUIP_CONF_BUFFER_SIZE=2048
+CFLAGS += -DREST_MAX_CHUNK_SIZE=1024
+CFLAGS += -DCOAP_MAX_HEADER_SIZE=640
+endif
+
+# linker optimizations
+SMALL=1
+
+
+# REST Engine shall use Erbium CoAP implementation
+APPS += er-coap
+APPS += rest-engine
+APPS += arduino
+
+include $(CONTIKI)/Makefile.include
+include $(CONTIKI)/apps/arduino/Makefile.include
+
+$(CONTIKI)/tools/tunslip6:      $(CONTIKI)/tools/tunslip6.c
+	(cd $(CONTIKI)/tools && $(MAKE) tunslip6)
+
+connect-router: $(CONTIKI)/tools/tunslip6
+	sudo $(CONTIKI)/tools/tunslip6 aaaa::1/64
+
+connect-router-cooja:   $(CONTIKI)/tools/tunslip6
+	sudo $(CONTIKI)/tools/tunslip6 -a 127.0.0.1 aaaa::1/64
+
+connect-minimal:
+	sudo ip address add fdfd::1/64 dev tap0

examples/osd/arduino-climate/README.md

@@ -0,0 +1,11 @@
+Arduino compatibility example
+=============================
+
+This example shows that it is now possible to re-use arduino sketches in
+Contiki. This example documents the necessary magic. Arduino specifies
+two routines, `setup` and `loop`. Before `setup` is called, the
+framework initializes hardware. In original Arduino, all this is done in
+a `main` function (in C). For contiki we define a process that does the
+same.
+
+See the documentation file in apps/contiki-compat/README.md

examples/osd/arduino-climate/arduino-example.c

@@ -0,0 +1,2 @@
+#include <arduino-process.h>
+AUTOSTART_PROCESSES(&arduino_sketch);

examples/osd/arduino-climate/arduino-merkurbaord.geany

@@ -0,0 +1,53 @@
+[file_prefs]
+final_new_line=true
+ensure_convert_new_lines=false
+strip_trailing_spaces=false
+replace_tabs=false
+
+[indentation]
+indent_width=4
+indent_type=1
+indent_hard_tab_width=8
+detect_indent=false
+detect_indent_width=false
+indent_mode=2
+
+[project]
+name=arduino-merkurbaord
+base_path=/home/harald/install/osd-contiki/examples/osd/arduino-climate/
+description=
+file_patterns=
+
+[long line marker]
+long_line_behaviour=1
+long_line_column=72
+
+[files]
+current_page=0
+FILE_NAME_0=0;C++;0;EUTF-8;1;1;0;%2Fhome%2Fharald%2Finstall%2Fosd-contiki%2Fexamples%2Fosd%2Farduino-merkurboard%2Fsketch.pde;0;4
+
+[VTE]
+last_dir=/home/harald
+
+[build-menu]
+NF_00_LB=_Make
+NF_00_CM=make TARGET=osd-merkur-256
+NF_00_WD=
+NF_01_LB=Make flash
+NF_01_CM=make TARGET=osd-merkur-256 flash
+NF_01_WD=
+NF_03_LB=Make Clean
+NF_03_CM=make clean TARGET=osd-merkur-256
+NF_03_WD=
+C++FT_00_LB=_Kompilieren
+C++FT_00_CM=make TARGET=osd-merkur-256
+C++FT_00_WD=
+C++FT_01_LB=_Erstellen
+C++FT_01_CM=make TARGET=osd-merkur-256 flash
+C++FT_01_WD=
+filetypes=C++;
+
+[editor]
+line_wrapping=false
+line_break_column=72
+auto_continue_multiline=true

examples/osd/arduino-climate/flash.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+make TARGET=osd-merkur-128 flash

examples/osd/arduino-climate/project-conf.h

@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2010, Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *
+ */
+
+#ifndef PROJECT_RPL_WEB_CONF_H_
+#define PROJECT_RPL_WEB_CONF_H_
+
+#define PLATFORM_HAS_LEDS    1
+//#define PLATFORM_HAS_BUTTON  1
+#define PLATFORM_HAS_BATTERY 1
+
+#define SICSLOWPAN_CONF_FRAG	1
+
+#define LOOP_INTERVAL		(30 * CLOCK_SECOND)
+
+/* Save energy */
+//#define RDC_CONF_PT_YIELD_OFF
+
+/* For Debug: Dont allow MCU sleeping between channel checks */
+//#undef RDC_CONF_MCU_SLEEP
+//#define RDC_CONF_MCU_SLEEP       0
+
+/* Disabling RDC for demo purposes. Core updates often require more memory. */
+/* For projects, optimize memory and enable RDC again. */
+// #undef NETSTACK_CONF_RDC
+//#define NETSTACK_CONF_RDC     nullrdc_driver
+
+/* Increase rpl-border-router IP-buffer when using more than 64. */
+#undef REST_MAX_CHUNK_SIZE
+#define REST_MAX_CHUNK_SIZE    64
+
+/* Estimate your header size, especially when using Proxy-Uri. */
+/*
+#undef COAP_MAX_HEADER_SIZE
+#define COAP_MAX_HEADER_SIZE    70
+*/
+
+/* The IP buffer size must fit all other hops, in particular the border router. */
+
+#undef UIP_CONF_BUFFER_SIZE
+#define UIP_CONF_BUFFER_SIZE    256
+
+
+/* Multiplies with chunk size, be aware of memory constraints. */
+#undef COAP_MAX_OPEN_TRANSACTIONS
+#define COAP_MAX_OPEN_TRANSACTIONS   4
+
+/* Must be <= open transaction number, default is COAP_MAX_OPEN_TRANSACTIONS-1. */
+/*
+#undef COAP_MAX_OBSERVERS
+#define COAP_MAX_OBSERVERS      2
+*/
+
+/* Filtering .well-known/core per query can be disabled to save space. */
+/*
+#undef COAP_LINK_FORMAT_FILTERING
+#define COAP_LINK_FORMAT_FILTERING      0
+*/
+
+/* Save some memory for the sky platform. */
+/*
+#undef NBR_TABLE_CONF_MAX_NEIGHBORS
+#define NBR_TABLE_CONF_MAX_NEIGHBORS     10
+#undef UIP_CONF_MAX_ROUTES
+#define UIP_CONF_MAX_ROUTES   10
+*/
+
+/* Reduce 802.15.4 frame queue to save RAM. */
+/*
+#undef QUEUEBUF_CONF_NUM
+#define QUEUEBUF_CONF_NUM       4
+*/
+
+/*
+#undef SICSLOWPAN_CONF_FRAG
+#define SICSLOWPAN_CONF_FRAG	1
+*/
+
+#endif /* PROJECT_RPL_WEB_CONF_H_ */

examples/osd/arduino-climate/resources/res-htu21dhum.c

@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2013, Institute for Pervasive Computing, ETH Zurich
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file is part of the Contiki operating system.
+ */
+
+/**
+ * \file
+ *      Moisture resource
+ * \author
+ *      Harald Pichler <harald@the-develop.net>
+ */
+
+#include "contiki.h"
+
+#include <string.h>
+#include "rest-engine.h"
+#include "Arduino.h"
+
+static void res_get_handler(void *request, void *response, uint8_t *buffer, uint16_t preferred_size, int32_t *offset);
+
+/* A simple getter example. Returns the reading from the sensor with a simple etag */
+RESOURCE(res_htu21dhum,
+         "title=\"Moisture status\";rt=\"Moisture\"",
+         res_get_handler,
+         NULL,
+         NULL,
+         NULL);
+
+extern  char htu21d_hum_s[8];
+
+
+static void
+res_get_handler(void *request, void *response, uint8_t *buffer, uint16_t preferred_size, int32_t *offset)
+{
+  
+  unsigned int accept = -1;
+  REST.get_header_accept(request, &accept);
+
+  if(accept == -1 || accept == REST.type.TEXT_PLAIN) {
+    REST.set_header_content_type(response, REST.type.TEXT_PLAIN);
+    snprintf((char *)buffer, REST_MAX_CHUNK_SIZE, "%s", htu21d_hum_s);
+
+    REST.set_response_payload(response, buffer, strlen((char *)buffer));
+  } else if(accept == REST.type.APPLICATION_JSON) {
+    REST.set_header_content_type(response, REST.type.APPLICATION_JSON);
+    snprintf((char *)buffer, REST_MAX_CHUNK_SIZE, "{'moisture':%s}", htu21d_hum_s);
+
+    REST.set_response_payload(response, buffer, strlen((char *)buffer));
+  } else {
+    REST.set_response_status(response, REST.status.NOT_ACCEPTABLE);
+    const char *msg = "Supporting content-types text/plain and application/json";
+    REST.set_response_payload(response, msg, strlen(msg));
+  }
+}

examples/osd/arduino-climate/resources/res-htu21dtemp.c

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2013, Institute for Pervasive Computing, ETH Zurich
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * This file is part of the Contiki operating system.
+ */
+
+/**
+ * \file
+ *      Moisture resource
+ * \author
+ *      Harald Pichler <harald@the-develop.net>
+ */
+
+#include "contiki.h"
+
+#include <string.h>
+#include "rest-engine.h"
+#include "Arduino.h"
+
+static void res_get_handler(void *request, void *response, uint8_t *buffer, uint16_t preferred_size, int32_t *offset);
+
+/* A simple getter example. Returns the reading from the sensor with a simple etag */
+RESOURCE(res_htu21dtemp,
+         "title=\"Temperature status\";rt=\"Temperatur\"",
+         res_get_handler,
+         NULL,
+         NULL,
+         NULL);
+
+extern  char htu21d_temp_s[8];
+
+static void
+res_get_handler(void *request, void *response, uint8_t *buffer, uint16_t preferred_size, int32_t *offset)
+{
+  
+  unsigned int accept = -1;
+  REST.get_header_accept(request, &accept);
+
+  if(accept == -1 || accept == REST.type.TEXT_PLAIN) {
+    REST.set_header_content_type(response, REST.type.TEXT_PLAIN);
+    snprintf((char *)buffer, REST_MAX_CHUNK_SIZE, "%s", htu21d_temp_s);
+
+    REST.set_response_payload(response, buffer, strlen((char *)buffer));
+  } else if(accept == REST.type.APPLICATION_JSON) {
+    REST.set_header_content_type(response, REST.type.APPLICATION_JSON);
+    snprintf((char *)buffer, REST_MAX_CHUNK_SIZE, "{'temperature':%s}", htu21d_temp_s);
+
+    REST.set_response_payload(response, buffer, strlen((char *)buffer));
+  } else {
+    REST.set_response_status(response, REST.status.NOT_ACCEPTABLE);
+    const char *msg = "Supporting content-types text/plain and application/json";
+    REST.set_response_payload(response, msg, strlen(msg));
+  }
+}

examples/osd/arduino-climate/run.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+# For the ages-old bootloader (before 2014) you want to use
+# BOOTLOADER_GET_MAC=0x0001f3a0 as parameter to make below.
+make clean TARGET=osd-merkur-128
+make TARGET=osd-merkur-128

examples/osd/arduino-climate/sketch.pde

@@ -0,0 +1,62 @@
+/*
+ * Sample arduino sketch using contiki features.
+ * We turn the LED off 
+ * We allow read the moisture sensor
+ * Unfortunately sleeping for long times in loop() isn't currently
+ * possible, something turns off the CPU (including PWM outputs) if a
+ * Proto-Thread is taking too long. We need to find out how to sleep in
+ * a Contiki-compatible way.
+ * Note that for a normal arduino sketch you won't have to include any
+ * of the contiki-specific files here, the sketch should just work.
+ */
+
+#include <Wire.h>
+#include "Adafruit_HTU21DF.h"
+
+extern "C" {
+#include "arduino-process.h"
+#include "rest-engine.h"
+
+Adafruit_HTU21DF htu = Adafruit_HTU21DF();
+
+extern resource_t res_htu21dtemp, res_htu21dhum, res_battery;
+float htu21d_hum;
+float htu21d_temp;
+char  htu21d_hum_s[8];
+char  htu21d_temp_s[8];
+
+#define LED_PIN 4
+}
+
+void setup (void)
+{
+    // switch off the led
+    pinMode(LED_PIN, OUTPUT);
+    digitalWrite(LED_PIN, HIGH);
+    // htu21d sensor
+    if (!htu.begin()) {
+      printf("Couldn't find sensor!");
+    }
+    // init coap resourcen
+    rest_init_engine ();
+#pragma GCC diagnostic ignored "-Wwrite-strings"
+    rest_activate_resource (&res_htu21dtemp, "s/temp");
+    rest_activate_resource (&res_htu21dhum, "s/hum");
+    rest_activate_resource (&res_battery, "s/battery");
+#pragma GCC diagnostic pop    
+    mcu_sleep_set(128); // Power consumtion 278uA; average over 20 minutes
+}
+
+// at project-conf.h
+// LOOP_INTERVAL		(30 * CLOCK_SECOND)
+void loop (void)
+{
+    htu21d_temp = htu.readTemperature();
+    htu21d_hum = htu.readHumidity();
+    dtostrf(htu21d_temp , 0, 2, htu21d_temp_s );   
+    dtostrf(htu21d_hum , 0, 2, htu21d_hum_s );
+      
+//  debug only   
+//  printf("Temp: '%s'",htu21d_temp_s);
+//  printf("\t\tHum: '%s'\n",htu21d_hum_s);
+}