mbed

Revision 0:7d2088337345, committed 12 Dec 2010

Comitter:

Ali Saidi

Date:

Sun Dec 12 05:36:26 2010 +0000

Child:

1:208b4f080b2f

Commit message:

Initial revision

Changed in this revision

TxIR.cpp	Show annotated file Show diff for this revision Revisions of this file
TxIR.hpp	Show annotated file Show diff for this revision Revisions of this file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TxIR.cpp	Sun Dec 12 05:36:26 2010 +0000
@@ -0,0 +1,78 @@
+
+/******************************************************************************
+ * Low level infrared transmission
+ * This library provides a low level interface to send IR commands. in principle
+ * other higher level IR type remotes could be build on top of this. I wrote
+ * this code to send IR commands to a Nikon camera, which it works rather well
+ * for. 
+ *
+ * Copyright (C) 2010 Ali Saidi
+ * 
+ * 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 "TxIR.hpp"
+ 
+
+void
+TxIR::doAction()
+{
+    if (pos >= len) {
+        delete [] data;
+        _inUse = false;
+        txPin.write(0);
+        return;
+    }
+        
+    delay.attach_us(this, &TxIR::doAction, data[pos++]);
+    if (high)
+        txPin.write(0);
+    else
+        txPin.write(0.5);
+   high = !high;
+}
+
+bool
+TxIR::txSeq(unsigned freq, unsigned _len, const unsigned *_data) 
+{
+    // @todo a lock or semaphore should be used here
+    if (inUse())
+        return false;
+    _inUse = true;
+    
+    // keep a copy of the data, so it can't change
+    len = _len;
+    data = new unsigned[len];
+    memcpy(data, _data, len * sizeof(unsigned));
+    pos = 0;
+    
+    // setup the PWM
+    txPin.write(0.0);
+    txPin.period_us(freq);
+    
+    // Get the interrupt ready
+    delay.detach();
+    high = true;
+    delay.attach_us(this, &TxIR::doAction, data[pos++]);
+    
+    // Begin
+    txPin.write(0.5);
+    
+    return true;
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TxIR.hpp	Sun Dec 12 05:36:26 2010 +0000
@@ -0,0 +1,87 @@
+
+/******************************************************************************
+ * Low level infrared transmission
+ * This library provides a low level interface to send IR commands. in principle
+ * other higher level IR type remotes could be build on top of this. I wrote
+ * this code to send IR commands to a Nikon camera, which it works rather well
+ * for. 
+ *
+ * Copyright (C) 2010 Ali Saidi
+ * 
+ * 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.
+ */
+ 
+ #ifndef __TXIR_HPP__
+ #define __TXIR_HPP__
+ 
+ #include <mbed.h>
+ 
+ class TxIR {
+    private:
+        /** Function that does the work */
+        void doAction();
+        
+        /** A timeout that is used to do the next action, so we don't spin
+          * for the entire IR sequence
+          */
+        Timeout delay;
+        
+        /** If the stack is currently busy transmitting something */
+        bool _inUse;
+        
+        /** A local copy of the data so the caller can muck with their own */
+        unsigned *data;
+        
+        /** length of the array */
+        unsigned len;
+        
+        /** Current location in the array */
+        unsigned pos;
+        
+        /** The pin used to send the IR commands */
+        PwmOut txPin;
+        
+        /** If we're currenting sending data or waiting */
+        bool high;
+        
+    public:
+        /** Initialize the TxIR library
+         * @param pin a pin on the mbed that is PWM capable
+         */
+        TxIR(PinName pin)
+            : _inUse(false), txPin(pin)
+        {}
+        
+        /** If something is currently being sent 
+          * @return is something being tranmitted currently 
+          * @todo is there a lock library available, this certainly isn't safe
+          */
+        bool inUse() { return _inUse; }
+        
+        /** Transmit an IR sequence
+          * @param freq the modulation frequency in us normally ~40kHz -> 26us
+          * @param len the number of modulation changes to send (length of data) 
+          * @param data an array of on/off times in us that will be transmitted
+          * @return transmission has begun
+          */
+        bool txSeq(unsigned freq, unsigned len, const unsigned *data);
+};
+
+#endif // __TXIR_HPP__
+          
\ No newline at end of file