WindVaneReadC gives instantaneous compass heading reading from the wind vane.

diff --git a/tos/platforms/tmirws/sensors/WindVaneReadC.nc b/tos/platforms/tmirws/sensors/WindVaneReadC.nc
new file mode 100644 (file)
index 0000000..3b46734
--- /dev/null
+++ b/tos/platforms/tmirws/sensors/WindVaneReadC.nc
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2008, Titanium Mirror, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * - Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ * - 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.
+ * - Neither the name of Titanium Mirror, Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT
+ * OWNER 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.
+ */
+ 
+/**
+ * Take an instantaneous reading of the wind vane position, in degrees.
+ * 
+ * @author R. Steve McKown <smckown@gmail.com>
+ */
+ 
+configuration WindVaneReadC {
+  provides interface Read<uint16_t>;
+}
+implementation {
+  components WindVaneReadP;
+  Read = WindVaneReadP;
+
+  components new MultiSampleC(uint16_t, 4);
+  WindVaneReadP.Count -> MultiSampleC;
+  WindVaneReadP.SubRead -> MultiSampleC;
+
+  components WindVaneAdcP;
+  MultiSampleC.AdcConfigure -> WindVaneAdcP;
+
+  components HalWindVaneC;
+  WindVaneReadP.WPower -> HalWindVaneC.WPower;
+  WindVaneReadP.WDead -> HalWindVaneC.WDead;
+
+  components new StateC();
+  WindVaneReadP.State -> StateC;
+}

diff --git a/tos/platforms/tmirws/sensors/WindVaneReadP.nc b/tos/platforms/tmirws/sensors/WindVaneReadP.nc
new file mode 100644 (file)
index 0000000..2076e23
--- /dev/null
+++ b/tos/platforms/tmirws/sensors/WindVaneReadP.nc
@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2008, Titanium Mirror, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * - Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ * - 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.
+ * - Neither the name of Titanium Mirror, Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT
+ * OWNER 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.
+ */
+ 
+/**
+ * Take an instantaneous reading of the wind vane position.
+ * 
+ * @author R. Steve McKown <smckown@gmail.com>
+ */
+ 
+module WindVaneReadP @safe()
+{
+  provides interface Read<uint16_t>;
+  uses {
+    interface Get<uint16_t> as Count;
+    interface Read<uint16_t> as SubRead;
+    interface GeneralIO as WPower;
+    interface GeneralIO as WDead;
+    interface State;
+  }
+}
+implementation
+{
+  enum {
+    S_IDLE = 0,
+    S_READ,
+    S_CHECK,
+    S_OUTPUT,
+
+    /* The wind vane has a dead zone where it returns an ADC value that also
+     * represents another angular location.  Therefore, we implement special
+     * dead zone checking over a certain range of return values from the
+     * wind vane.
+     *
+     * Note: the wind vane's dead zone is probably 5-10 degrees.  We would be
+     * more accurate if we took the ADC range over 350 or 355 degrees, then
+     * added 1/2 of the dead zone as an offset.  However, without this logic,
+     * the wind vane appears more than accurate enough.  It is less accurate
+     * within the dead zone, of course, but would be even if we did implement
+     * the extra logic.
+     */
+    DEAD_BEGIN = 6000,         /* 4 12-bit ADC readings; about 120 degrees */
+    DEAD_END = 9000,           /* About 198 degrees */
+    DEAD_THRESH = 14472,       /* > when checking means in dead zone */
+  };
+
+  char m_msg[80];
+
+  command error_t Read.read()
+  {
+    if (!(call State.isIdle()))
+      return EBUSY;
+
+    call WPower.set();
+    if (call SubRead.read() == SUCCESS) {
+      call State.forceState(S_READ);
+      return SUCCESS;
+    } else {
+      call WPower.clr();
+      return FAIL;
+    }
+  }
+
+  void signalReadDone(error_t error, uint16_t value)
+  {
+    call WDead.makeInput();
+    call WPower.clr();
+
+    /* Value is the sum of multiple 12-bit ADC acquisitions, per the attached
+     * MultiSampleC component.  Convert the value to degrees.  Note, the values
+     * 360 and 0 (zero) represent the same angular position.  We don't do a
+     * modulus operation here because we fully expect the client will do
+     * additional processing that will likely involve a modulus function anyway.
+     */
+    value = (uint16_t)(((uint32_t)(value / call Count.get()) * 360 + 2047) /
+       4096);
+
+    call State.toIdle();
+    signal Read.readDone(error, value);
+  }
+
+  event void SubRead.readDone(error_t error, uint16_t result)
+  {
+    static uint16_t m_value;
+
+    if (error != SUCCESS) {
+      signalReadDone(error, 0);
+      return;
+    }
+
+    switch (call State.getState()) {
+      case S_READ:
+       if (result < DEAD_BEGIN || result > DEAD_END)
+         signalReadDone(SUCCESS, result);
+       else {
+         m_value = result;
+         call WDead.makeOutput();
+         if (call SubRead.read() == SUCCESS)
+           call State.forceState(S_CHECK);
+         else
+           signalReadDone(FAIL, 0);
+       }
+       break;
+      case S_CHECK:
+       signalReadDone(SUCCESS, (result > DEAD_THRESH) ? 0 : m_value);
+       break;
+    }
+  } 
+}