grovewfs: Initial implementation

This driver implements support for the Grove Water Flow sensor.  It
uses an integrated hall effect sensor, connected to a GPIO configured
as an interrupt, to compute water flow in LPM (Liters Per Minute).

Signed-off-by: Jon Trulson <jtrulson@ics.com>
Signed-off-by: Zion Orent <zorent@ics.com>
Signed-off-by: John Van Drasek <john.r.van.drasek@intel.com>

examples/c++/CMakeLists.txt

@@ -112,6 +112,7 @@ add_executable (tm1637-example tm1637.cxx)
 add_executable (zfm20-example zfm20.cxx)
 add_executable (zfm20-register-example zfm20-register.cxx)
 add_executable (uln200xa-example uln200xa.cxx)
+add_executable (grovewfs-example grovewfs.cxx)
 
 include_directories (${PROJECT_SOURCE_DIR}/src/hmc5883l)
 include_directories (${PROJECT_SOURCE_DIR}/src/grove)
@@ -202,6 +203,7 @@ include_directories (${PROJECT_SOURCE_DIR}/src/waterlevel)
 include_directories (${PROJECT_SOURCE_DIR}/src/tm1637)
 include_directories (${PROJECT_SOURCE_DIR}/src/zfm20)
 include_directories (${PROJECT_SOURCE_DIR}/src/uln200xa)
+include_directories (${PROJECT_SOURCE_DIR}/src/grovewfs)
 
 target_link_libraries (hmc5883l-example hmc5883l ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (groveled-example grove ${CMAKE_THREAD_LIBS_INIT})
@@ -315,3 +317,4 @@ target_link_libraries (tm1637-example tm1637 ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (zfm20-example zfm20 ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (zfm20-register-example zfm20 ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (uln200xa-example uln200xa ${CMAKE_THREAD_LIBS_INIT})
+target_link_libraries (grovewfs-example grovewfs ${CMAKE_THREAD_LIBS_INIT})

examples/c++/grovewfs.cxx

@@ -0,0 +1,78 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2014 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <unistd.h>
+#include <iostream>
+#include <signal.h>
+#include "grovewfs.h"
+
+using namespace std;
+
+int shouldRun = true;
+
+void sig_handler(int signo)
+{
+  if (signo == SIGINT)
+    shouldRun = false;
+}
+
+
+int main()
+{
+  signal(SIGINT, sig_handler);
+
+//! [Interesting]
+  // Instantiate a Grove Water Flow Sensor on digital pin D2
+  upm::GroveWFS* flow = new upm::GroveWFS(2);
+  
+  // set the flow counter to 0 and start counting
+  flow->clearFlowCounter();
+  flow->startFlowCounter();
+
+  while (shouldRun)
+    {
+      // we grab these (,illis and flowCount) just for display
+      // purposes in this example
+      uint32_t millis = flow->getMillis();
+      uint32_t flowCount = flow->flowCounter();
+
+      float fr = flow->flowRate();
+
+      // output milliseconds passed, flow count, and computed flow rate
+      cout << "Millis: " << millis << " Flow Count: " << flowCount;
+      cout << " Flow Rate: " << fr << " LPM" << endl;
+
+      // best to gather data for at least one second for reasonable
+      // results.
+      sleep(2);
+    }
+
+  flow->stopFlowCounter();
+//! [Interesting]
+
+  cout << "Exiting..." << endl;
+
+  delete flow;
+  return 0;
+}

examples/javascript/grovewfs.js

@@ -0,0 +1,69 @@
+/*jslint node:true, vars:true, bitwise:true, unparam:true */
+/*jshint unused:true */
+
+/*
+* Author: Zion Orent <zorent@ics.com>
+* Copyright (c) 2015 Intel Corporation.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+var waterFlow_lib = require('jsupm_grovewfs');
+
+// Instantiate a Grove Water Flow Sensor on digital pin D2
+var myWaterFlow_obj = new waterFlow_lib.GroveWFS(2);
+
+// set the flow counter to 0 and start counting
+myWaterFlow_obj.clearFlowCounter();
+myWaterFlow_obj.startFlowCounter();
+
+
+var millis, flowCount, fr;
+var myInterval = setInterval(function()
+{
+	// we grab these (millis and flowCount) just for display
+	// purposes in this example
+	millis = myWaterFlow_obj.getMillis();
+	flowCount = myWaterFlow_obj.flowCounter();
+
+	fr = myWaterFlow_obj.flowRate();
+
+	// output milliseconds passed, flow count, and computed flow rate
+	outputStr = "Millis: " + millis + " Flow Count: " + flowCount +
+	" Flow Rate: " + fr + " LPM";
+	console.log(outputStr);
+
+	// best to gather data for at least one second for reasonable
+	// results.
+}, 2000);
+
+
+// When exiting: clear interval and print message
+process.on('SIGINT', function()
+{
+	clearInterval(myInterval);
+	myWaterFlow_obj.stopFlowCounter();
+	myWaterFlow_obj = null
+	waterFlow_lib.cleanUp();
+	waterFlow_lib = null;
+
+	console.log("Exiting");
+	process.exit(0);
+});

examples/python/grovewfs.py

@@ -0,0 +1,64 @@
+#!/usr/bin/python
+# Author: Zion Orent <zorent@ics.com>
+# Copyright (c) 2015 Intel Corporation.
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import time, sys, signal, atexit
+import pyupm_grovewfs as upmGrovewfs
+
+# Instantiate a Grove Water Flow Sensor on digital pin D2
+myWaterFlow = upmGrovewfs.GroveWFS(2)
+
+
+## Exit handlers ##
+# This stops python from printing a stacktrace when you hit control-C
+def SIGINTHandler(signum, frame):
+	raise SystemExit
+
+# This function lets you run code on exit,
+# including functions from myWaterFlow
+def exitHandler():
+	myWaterFlow.stopFlowCounter()
+	print "Exiting"
+	sys.exit(0)
+
+# Register exit handlers
+atexit.register(exitHandler)
+signal.signal(signal.SIGINT, SIGINTHandler)
+
+
+# set the flow counter to 0 and start counting
+myWaterFlow.clearFlowCounter()
+myWaterFlow.startFlowCounter()
+
+while (1):
+	# we grab these (millis and flowCount) just for display
+	# purposes in this example
+	millis = myWaterFlow.getMillis()
+	flowCount = myWaterFlow.flowCounter()
+
+	fr = myWaterFlow.flowRate()
+
+	# output milliseconds passed, flow count, and computed flow rate
+	outputStr = "Millis: {0} Flow Count: {1} Flow Rate: {2} LPM".format(
+	millis, flowCount, fr)
+	print outputStr
+	time.sleep(2)

src/grovewfs/CMakeLists.txt

@@ -0,0 +1,5 @@
+set (libname "grovewfs")
+set (libdescription "upm grove water flow sensor module")
+set (module_src ${libname}.cxx)
+set (module_h ${libname}.h)
+upm_module_init()

src/grovewfs/grovewfs.cxx

@@ -0,0 +1,121 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <iostream>
+
+#include "grovewfs.h"
+
+using namespace upm;
+using namespace std;
+
+GroveWFS::GroveWFS(int pin)
+{
+  if ( !(m_gpio = mraa_gpio_init(pin)) )
+    {
+      cerr << __FUNCTION__ << ": mraa_gpio_init() failed" << endl;
+      return;
+    }
+
+  mraa_gpio_dir(m_gpio, MRAA_GPIO_IN);
+
+  initClock();
+  m_flowCounter = 0;
+  m_isrInstalled = false;
+}
+
+GroveWFS::~GroveWFS()
+{
+  if (m_isrInstalled)
+    stopFlowCounter();
+
+  mraa_gpio_close(m_gpio);
+}
+
+void GroveWFS::initClock()
+{
+  gettimeofday(&m_startTime, NULL);
+}
+
+uint32_t GroveWFS::getMillis()
+{
+  struct timeval elapsed, now;
+  uint32_t elapse;
+
+  // get current time
+  gettimeofday(&now, NULL);
+
+  // compute the delta since m_startTime
+  if( (elapsed.tv_usec = now.tv_usec - m_startTime.tv_usec) < 0 ) 
+    {
+      elapsed.tv_usec += 1000000;
+      elapsed.tv_sec = now.tv_sec - m_startTime.tv_sec - 1;
+    } 
+  else 
+    {
+      elapsed.tv_sec = now.tv_sec - m_startTime.tv_sec;
+    }
+
+  elapse = (uint32_t)((elapsed.tv_sec * 1000) + (elapsed.tv_usec / 1000));
+
+  // never return 0
+  if (elapse == 0)
+    elapse = 1;
+
+  return elapse;
+}
+
+void GroveWFS::startFlowCounter()
+{
+  initClock();
+  // install our interrupt handler
+  mraa_gpio_isr(m_gpio, MRAA_GPIO_EDGE_RISING, 
+                &flowISR, this);
+
+  m_isrInstalled = true;
+}
+
+void GroveWFS::stopFlowCounter()
+{
+  // remove the interrupt handler
+  mraa_gpio_isr_exit(m_gpio);
+
+  m_isrInstalled = false;
+}
+
+void GroveWFS::flowISR(void *ctx)
+{
+  upm::GroveWFS *This = (upm::GroveWFS *)ctx;
+  This->m_flowCounter++;
+}
+
+float GroveWFS::flowRate()
+{
+  uint32_t millis = getMillis();
+  uint32_t flow = flowCounter();
+  
+  // 7.5 comes from the seeedstudio page, see the confusing datasheet :)
+  float flowRate = (float(flow) * 7.5) / ((float(millis) / 1000.0) * 60.0);
+
+  return flowRate;
+}

src/grovewfs/grovewfs.h

@@ -0,0 +1,137 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#pragma once
+
+#include <string>
+#include <stdint.h>
+#include <sys/time.h>
+#include <mraa/gpio.h>
+
+namespace upm {
+
+  /**
+   * @brief UPM module for the Grove Water Flow sensor
+   * @defgroup grovewfs libupm-grovewfs
+   * @ingroup seeed gpio liquid
+   */
+
+  /**
+   * @sensor grovewfs
+   * @comname Grove Water Flow Sensor
+   * @type liquid
+   * @man seeed
+   * @con gpio
+
+   * @brief C++ API for the Grove Water Flow Sensor
+   *
+   * This sensor is used to measure water flow, in LPM (Liters Per
+   * Minute).  It incorporates a Hall Effect Sensor.  The UPM module
+   * defines an interrupt routine to be triggered on each low pulse,
+   * keeping count.  This device requires a 10K pullup resistor for
+   * the signal line (yellow wire).  There is a schematic diagram on
+   * the seeedstudio site (3/2015):
+   * http://www.seeedstudio.com/wiki/index.php?title=G1/2_Water_Flow_sensor
+   *
+   * However, be careful in wiring this up - the schematic appears to
+   * have a bug in it: the lower left connection of the signal line
+   * (yellow) to Vcc (red) should not be there.  The sensor may work
+   * with this connection, but probably not for very long.
+   *
+   *
+   * @snippet grovewfs.cxx Interesting
+   */
+  class GroveWFS {
+  public:
+    /**
+     * GroveWFS constructor
+     *
+     * @param pin digital pin to use
+     */
+    GroveWFS(int pin);
+    /**
+     * GroveWFS Destructor
+     */
+    ~GroveWFS();
+    /**
+     * Return the number of milliseconds elapsed since initClock()
+     * was last called.
+     *
+     * @return elapsed milliseconds
+     */
+    uint32_t getMillis();
+
+    /**
+     * Reset the Clock
+     *
+     */
+    void initClock();
+
+    /**
+     * Reset the flow counter to 0.  The flow Counter should be
+     * stopped via stopFlowCounter() prior to calling this function.
+     *
+     */
+    void clearFlowCounter() { m_flowCounter = 0; };
+
+    /**
+     * Start the flow counter
+     *
+     */
+    void startFlowCounter();
+
+    /**
+     * Stop the flow counter
+     *
+     */
+    void stopFlowCounter();
+
+    /**
+     * Get the flow Counter
+     *
+     * @return the flow counter
+     */
+    uint32_t flowCounter() { return m_flowCounter; };
+
+    /**
+     * Flow Interrupt Service Routine
+     *
+     */
+    static void flowISR(void *ctx);
+
+    /**
+     * Compute the flow rate in liters per minute (LPM)
+     *
+     * @return the computed flow rate
+     */
+    float flowRate();
+
+  private:
+    volatile uint32_t m_flowCounter;
+    struct timeval m_startTime;
+    mraa_gpio_context m_gpio;
+    bool m_isrInstalled;
+  };
+}
+
+

src/grovewfs/jsupm_grovewfs.i

@@ -0,0 +1,8 @@
+%module jsupm_grovewfs
+%include "../upm.i"
+
+%{
+    #include "grovewfs.h"
+%}
+
+%include "grovewfs.h"

src/grovewfs/pyupm_grovewfs.i

@@ -0,0 +1,9 @@
+%module pyupm_grovewfs
+%include "../upm.i"
+
+%feature("autodoc", "3");
+
+%include "grovewfs.h"
+%{
+    #include "grovewfs.h"
+%}