Revision 0:0012aa4908fa, committed 2015-06-07

Comitter:

jyrodriguezg

Date:

Sun Jun 07 04:34:47 2015 +0000

Commit message:

Librer?a keypad

Changed in this revision

diff -r 000000000000 -r 0012aa4908fa FPointer.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/FPointer.h	Sun Jun 07 04:34:47 2015 +0000
@@ -0,0 +1,163 @@
+/*
+    Copyright (c) 2011 Andy Kirkham
+ 
+    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 AJK_FPOINTER_H
+#define AJK_FPOINTER_H
+
+namespace AjK {
+
+class FPointerDummy;
+
+/** FPointer - Adds callbacks that take and return a 32bit uint32_t data type.
+ *
+ * The Mbed library supplies a callback using the FunctionPointer object as 
+ * defined in FunctionPointer.h  However, this callback system does not allow
+ * the caller to pass a value to the callback. Likewise, the callback itself
+ * cannot return a value.
+ *
+ * FPointer operates in the same way but allows the callback function to be
+ * passed one arg, a uint32_t value. Additionally, the callback can return
+ * a single uint32_t value. The reason for using uint32_t is that the Mbed
+ * and the microcontroller (LPC1768) have a natural data size of 32bits and
+ * this means we can use the uint32_t as a pointer. See example1.h for more
+ * information. This example passes an "int" by passing a pointer to that
+ * int as a 32bit value. Using this technique you can pass any value you like.
+ * All you have to do is pass a pointer to your value cast to (uint32_t). Your
+ * callback can the deference it to get the original value.
+ *
+ * example2.h shows how to do the same thing but demostrates how to specify
+ * the callback into a class object/method.
+ *
+ * Finally, example3.h shows how to pass multiple values. In this example we
+ * define a data structure and in the callback we pass a pointer to that
+ * data structure thus allowing the callback to again get the values.
+ *
+ * Note, when passing pointers to variables to the callback, if the callback
+ * function/method changes that variable's value then it will also change the
+ * value the caller sees. If C pointers are new to you, you are strongly
+ * advised to read up on the subject. It's pointers that often get beginners
+ * into trouble when mis-used.
+ *
+ * @see example1.h
+ * @see example2.h
+ * @see example3.h
+ * @see http://mbed.org/handbook/C-Data-Types
+ * @see http://mbed.org/projects/libraries/svn/mbed/trunk/FunctionPointer.h
+ */
+class FPointer {
+
+protected:
+
+    //! C callback function pointer.
+    uint32_t (*c_callback)(uint32_t); 
+    
+    //! C++ callback object/method pointer (the object part).
+    FPointerDummy  *obj_callback;
+    
+    //! C++ callback object/method pointer (the method part).
+    uint32_t (FPointerDummy::*method_callback)(uint32_t);
+
+public:
+    
+    /** Constructor
+     */
+    FPointer() {
+        c_callback      = NULL;
+        obj_callback    = NULL;
+        method_callback = NULL;
+    }
+    
+    /** attach - Overloaded attachment function.
+     *
+     * Attach a C type function pointer as the callback.
+     *
+     * Note, the callback function prototype must be:-
+     * @code
+     * uint32_t myCallbackFunction(uint32_t);
+     * @endcode
+     * @param A C function pointer to call.
+     */
+    void attach(uint32_t (*function)(uint32_t) = 0) { c_callback = function; }
+    
+    /** attach - Overloaded attachment function.
+     *
+     * Attach a C++ type object/method pointer as the callback.
+     *
+     * Note, the callback method prototype must be:-
+     * @code
+     *     public:
+     *         uint32_t myCallbackFunction(uint32_t);
+     * @endcode
+     * @param A C++ object pointer.
+     * @param A C++ method within the object to call.
+     */
+    template<class T> 
+    void attach(T* item, uint32_t (T::*method)(uint32_t)) { 
+        obj_callback    = (FPointerDummy *)item; 
+        method_callback = (uint32_t (FPointerDummy::*)(uint32_t))method; 
+    }
+
+    /** call - Overloaded callback initiator.
+     *
+     * call the callback function.
+     *
+     * @param uint32_t The value to pass to the callback.
+     * @return uint32_t The value the callback returns.
+     */
+    uint32_t call(uint32_t arg) {
+        if (c_callback != NULL) {
+            return (*c_callback)(arg);
+        }
+        else {
+            if (obj_callback  != NULL && method_callback != NULL) {
+                return (obj_callback->*method_callback)(arg);
+            }
+        }
+        return (uint32_t)NULL;
+    }
+    
+    /** call - Overloaded callback initiator.
+     *
+     * Call the callback function without passing an argument.
+     * The callback itself is passed NULL. Note, the callback
+     * prototype should still be <b>uint32_t callback(uint32_t)</b>.
+     *
+     * @return uint32_t The value the callback returns.
+     */
+    uint32_t call(void) {
+        if (c_callback != NULL) {
+            return (*c_callback)((uint32_t)NULL);
+        }
+        else {
+            if (obj_callback  != NULL && method_callback != NULL) {
+                return (obj_callback->*method_callback)((uint32_t)NULL);
+            }
+        }
+        return (uint32_t)NULL;
+    }    
+};
+
+}; // namespace AjK ends
+
+using namespace AjK;
+
+#endif

diff -r 000000000000 -r 0012aa4908fa keypad.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/keypad.cpp	Sun Jun 07 04:34:47 2015 +0000
@@ -0,0 +1,115 @@
+#include "keypad.h"
+
+Keypad::Keypad(PinName row3, PinName row2, PinName row1, PinName row0,
+               PinName col3, PinName col2, PinName col1, PinName col0,
+               int debounce_ms):
+    _row0(row0), _row1(row1), _row2(row2), _row3(row3),
+    _cols(col0, col1, col2, col3)
+{
+    _debounce = debounce_ms;
+    _rows[0] = &_row0;
+    _rows[1] = &_row1;
+    _rows[2] = &_row2;
+    _rows[3] = &_row3;
+    for (int r = 0; r < row_count; r++)
+        _rows[r]->mode(PullUp);
+   // _cols.mode(OpenDrain);
+    _cols.output();
+}
+
+void Keypad::_setupFallTrigger(void)
+{
+    for (int r = 0; r < row_count; r++)
+        _rows[r]->fall(this, &Keypad::_callback);
+}
+
+void Keypad::Start(void)
+{
+    /* make the columns zero so they can pull rows down */
+    _cols = 0x00;
+}
+
+void Keypad::Stop(void)
+{
+    /* make the columns one so they cannot pull any rows down anymore */
+    _cols = ~0x00;
+}
+
+void Keypad::CallAfterInput(uint32_t (*fptr)(uint32_t index))
+{
+    _input.attach(fptr);
+    _setupFallTrigger();
+}
+
+int Keypad::DebouncedScan()
+{
+    /* debounce */
+    wait_ms(_debounce);
+
+    return Scan();
+}
+
+int Keypad::Scan()
+{
+    /* lookup row */
+    int r = -1;
+    for (r = 0; r < row_count; r++) {
+        if (*_rows[r] == 0)
+            break;
+    }
+
+    /* if we didn't find a valid row, return */
+    if (!(0 <= r && r < row_count))
+        return -1;
+
+    /* scan columns to find out which one pulls down the row */
+    int c = -1;
+    for (c = 0; c < col_count; c++) {
+        _cols = ~(1 << c);
+        if (*_rows[r] == 0)
+            break;
+    }
+
+    /* re-energize all columns */
+    Start();
+
+    /* if we didn't find a valid column, return */
+    if (!(0 <= c && c < col_count))
+        return -1;
+
+    return r * col_count + c;
+}
+
+int Keypad::DebouncedScanMultiple()
+{
+    /* debounce */
+    wait_ms(_debounce);
+
+    return ScanMultiple();
+}
+
+int Keypad::ScanMultiple()
+{
+    int res = 0;
+    for (int c = 0; c < col_count; c++) {
+        _cols = ~(1 << c);
+        for (int r = 0; r < row_count; r++) {
+            if (*_rows[r] == 0) {
+                res |= 1 << (r * col_count + c);
+            }
+        }
+    }
+
+    return res;
+}
+
+void Keypad::_callback()
+{
+    /* lookup */
+    int position = DebouncedScan();
+
+    /* call back a valid position */
+    if (position >= 0)
+        _input.call(position);
+}
+

diff -r 000000000000 -r 0012aa4908fa keypad.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/keypad.h	Sun Jun 07 04:34:47 2015 +0000
@@ -0,0 +1,127 @@
+/* mbed Keypad library, using user-defined interrupt callback
+ * Copyright (c) 2012 Yoong Hor Meng
+ *
+ * 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 KEYPAD_H
+#define KEYPAD_H
+
+#include "mbed.h"
+#include "FPointer.h"
+
+/**
+ * An interrupt-based interface to 4x4 keypad.
+ *
+ * On each key pressed on a keypad, the index of the key is passed to a
+ * user-defined function. User is free to define what to be done with the
+ * input.
+ *
+ * This library makes use of
+ * @see http://mbed.org/cookbook/FPointer by Andy Kirkham
+ *
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "keypad.h"
+ *
+ * // Define your own keypad values
+ * char Keytable[] = { '1', '2', '3', 'A',
+ *                     '4', '5', '6', 'B',
+ *                     '7', '8', '9', 'C',
+ *                     '*', '0', '#', 'D'
+ *                   };
+ *
+ * uint32_t cbAfterInput(uint32_t index) {
+ *     printf("Index:%d => Key:%c\n", key, Keytable[index]);
+ *     return 0;
+ * }
+ *
+ * int main() {
+ *     Keypad keypad(p25, p26, p27, p28, p21, p22, p23, p24);
+ *     keypad.CallAfterInput(&cbAfterInput);
+ *     keypad.Start();
+ *
+ *     while (1) {
+ *         wait_ms(100);
+ *     }
+ * }
+ * @endcode
+ */
+class Keypad
+{
+public:
+    /** Create a Keypad interface
+     *
+     *  @param row<3..0>     Row data lines
+     *  @param col<3..0>     Column data lines
+     *  @param debounce_ms   Debounce in ms (Default to 20ms)
+     */
+    Keypad(PinName row3, PinName row2, PinName row1, PinName row0,
+           PinName col3, PinName col2, PinName col1, PinName col0,
+           int debounce_ms = 20);
+
+    /** Start the keypad interrupt routines
+     */
+    void Start(void);
+
+    /** Stop the keypad interrupt routines
+     */
+    void Stop(void);
+
+    /** Scan the keyboard for a debounced pressed key
+     */
+    int DebouncedScan(void);
+
+    /** Scan the keyboard for a pressed key
+     */
+    int Scan(void);
+
+    /** Scan the keyboard for multiple debounced pressed keys
+     */
+    int DebouncedScanMultiple(void);
+
+    /** Scan the keyboard for multiple pressed keys
+     */
+    int ScanMultiple(void);
+
+    /** User-defined function that to be called when a key is pressed
+     *  @param fptr           A function pointer takes a uint32_t and
+     *                        returns uint32_t
+     */
+    void CallAfterInput(uint32_t (*fptr)(uint32_t));
+
+protected:
+    static const int row_count = 4;
+    static const int col_count = 4;
+
+    InterruptIn      _row0;
+    InterruptIn      _row1;
+    InterruptIn      _row2;
+    InterruptIn      _row3;
+    InterruptIn      *_rows[row_count];
+    BusInOut         _cols;  // BusOut doesn't support mode() yet; need open drain to prevent short circuits...
+    int              _debounce;
+    FPointer         _input; // Called after each input
+
+    void _callback();
+    void _setupFallTrigger(void);
+};
+
+#endif // KEYPAD_H