Diff: example3a.cpp

Revision:

18:21ef26402365

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/example3a.cpp	Thu Apr 21 09:20:41 2011 +0000
@@ -0,0 +1,83 @@
+/*
+    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.
+    
+    @file          example3.cpp 
+    @purpose       Demos a simple filter.
+    @version       see ChangeLog.c
+    @author        Andy Kirkham
+*/
+
+/*
+    This example shows how to use the new callback system. In the old system
+    Mbed's FunctionPointer[1] type was used to store abd make calls to callbacks.
+    However, that limits the callback function prototype to void func(void);
+    which means we cannot pass parameters.
+    
+    This latest version of MODSERIAL now uses its own callback object. This allows
+    the passing of a pointer to a class that holds information about the MODSERIAL
+    object making the callback. As of version 1.18 one critcal piece of information
+    is passed, a pointer to the MODSERIAL object. This allows callbacks to use the
+    MODSERIAL functions and data.
+        
+    Additionally, since MODSERIAL and the callback parameter class MODSERIAL_IRQ_INFO
+    are friends, MODSERIAL_IRQ_INFO can access the protected functions of MODSERIAL.
+    This is used to ensure functions that can only be called during a callback
+    can be invoked from a callback. 
+    
+    [1] http://mbed.org/projects/libraries/svn/mbed/trunk/FunctionPointer.h    
+*/
+
+#ifdef COMPILE_EXAMPLE3_CODE_MODSERIAL
+
+#include "mbed.h"
+#include "MODSERIAL.h"
+
+DigitalOut led1(LED1);
+
+MODSERIAL pc(USBTX, USBRX);
+
+// The following callback is defined in example3b.cpp
+//! @see example3b.cpp
+void rxCallback(MODSERIAL_IRQ_INFO *info);
+
+int main() {
+    
+    int life_counter = 0;
+    
+    pc.baud(115200);
+    
+    pc.attach(&rxCallback, MODSERIAL::RxIrq);
+
+    while(1) {
+        // Echo back any chars we get except 'A' which is filtered by the rxCallback.
+        if (pc.readable()) {
+            pc.putc(pc.getc());
+        }
+        
+        // Toggle LED1 every so often to show we are alive.
+        if (life_counter++ == 1000000) {
+            life_counter = 0;
+            led1 = !led1;
+        }
+    }
+}
+
+#endif