TickerRSys.cpp

00001 /*
00002     Copyright (c) 2011 Andy Kirkham
00003  
00004     Permission is hereby granted, free of charge, to any person obtaining a copy
00005     of this software and associated documentation files (the "Software"), to deal
00006     in the Software without restriction, including without limitation the rights
00007     to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008     copies of the Software, and to permit persons to whom the Software is
00009     furnished to do so, subject to the following conditions:
00010  
00011     The above copyright notice and this permission notice shall be included in
00012     all copies or substantial portions of the Software.
00013  
00014     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015     IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016     FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017     AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018     LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019     OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00020     THE SOFTWARE.
00021 */
00022 
00023 // Mimic Mbed's Ticker class but using RIT
00024 // (note, only goes to milliseconds level not microseconds!)
00025 
00026 #include "TickersSys.h"
00027 
00028 namespace AjK {
00029 
00030 // Create a Ticker1 controller.
00031 TickerRSys _tickerRSys;
00032 
00033 // Nice and simple ISR, just call the class standard handler.
00034 extern "C" void RIT_IRQHandler(void) __irq 
00035 {
00036     _tickerRSys.isr();    
00037 }
00038 
00039 TickerRSys::TickerRSys(void)
00040 {    
00041     LPC_SC->PCONP |= (1UL << 16);   // RIT On
00042     
00043     switch ((LPC_SC->PCLKSEL1 >> 26) & 0x3) {
00044         case 0: LPC_RIT->RICOMPVAL = (96000000L / 4 / 1000); break; /* CCLK / 4 */
00045         case 1: LPC_RIT->RICOMPVAL = (96000000L / 1 / 1000); break; /* CCLK / 1 */
00046         case 2: LPC_RIT->RICOMPVAL = (96000000L / 2 / 1000); break; /* CCLK / 2 */
00047         case 3: LPC_RIT->RICOMPVAL = (96000000L / 8 / 1000); break; /* CCLK / 8 */
00048     }
00049     
00050     NVIC_EnableIRQ(RIT_IRQn);
00051     LPC_RIT->RICTRL     = 0x0000000A;
00052 }
00053 
00054 void 
00055 TickerRSys::addTicker(Ticker4 *t)
00056 {
00057     tickers.push_back(t);   
00058 }
00059 
00060 void 
00061 TickerRSys::delTicker(Ticker4 *t)
00062 {
00063     for (list<Ticker4 *>::iterator itor = tickers.begin(); itor !=  tickers.end(); ++itor) {
00064         if ((*itor) == t) {
00065             itor = tickers.erase(itor);
00066             return;
00067         }
00068     }
00069 }
00070 
00071 void 
00072 TickerRSys::isr(void)
00073 {
00074     LPC_RIT->RICTRL |= 0x1; /* Dismiss the IRQ. */
00075     
00076     if (tickers.empty()) return;
00077     
00078     for (list<Ticker4 *>::iterator itor = tickers.begin(); itor !=  tickers.end(); ++itor) {
00079         (*itor)->tick();
00080     }
00081     
00082 }    
00083 }; // namespace AjK ends.