Publishing (forking) it from Deurklink to Allseas-PHALCON-system.
Fork of MODSERIAL by
Diff: example3b.cpp
- Revision:
- 18:21ef26402365
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/example3b.cpp Thu Apr 21 09:20:41 2011 +0000 @@ -0,0 +1,78 @@ +/* + 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 example3b.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" + +void rxCallback(MODSERIAL_IRQ_INFO *info) { + + // Get the pointer to our MODSERIAL object that invoked this callback. + MODSERIAL *pc = info->serial; + + // info->serial points at the MODSERIAL instance so we can use it to call + // any of the public MODSERIAL functions that are normally available. So + // there's now no need to use the global version (pc in our case) inside + // callback functions. + char c = pc->rxGetLastChar(); // Where local pc variable is a pointer to the global MODSERIAL pc object. + + // The following is rather daft but demos the point. + // Don't allow the letter "A" go into the RX buffer. + // Basically acts as a filter to remove the letter "A" + // if it goes into the RX buffer. + if (c == 'A') { + // Note, we call the MODSERIAL_IRQ_INFO::rxDiscardLastChar() public function which + // is permitted access to the protected version of MODSERIAL::rxDiscardLastChar() + // within MODSERIAL (because they are friends). This ensures rxDiscardLastChar() + // can only be called within an rxCallback function. + info->rxDiscardLastChar(); + } +} + +#endif