94 lines
2.5 KiB
C
94 lines
2.5 KiB
C
/*
|
|
ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.
|
|
|
|
This file is part of ChibiOS/RT.
|
|
|
|
ChibiOS/RT is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
ChibiOS/RT is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
/*
|
|
* Buzzer driver for Olimex LPC-P2148.
|
|
* Uses the timer 1 for wave generation and a Virtual Timer for the sound
|
|
* duration.
|
|
* The driver also generates an event when the sound is done and the buzzer
|
|
* goes silent.
|
|
*/
|
|
#include <ch.h>
|
|
|
|
#include "lpc214x.h"
|
|
#include "board.h"
|
|
#include "buzzer.h"
|
|
|
|
EventSource BuzzerSilentEventSource;
|
|
|
|
#define StartCounter(t) ((t)->TC_EMR = 0xF1, (t)->TC_TCR = 1)
|
|
#define StopCounter(t) ((t)->TC_EMR = 0, (t)->TC_TCR = 2)
|
|
|
|
void InitBuzzer(void) {
|
|
|
|
chEvtInit(&BuzzerSilentEventSource);
|
|
|
|
/*
|
|
* Switches P0.12 and P0.13 to MAT1.0 and MAT1.1 functions.
|
|
* Enables Timer1 clock.
|
|
*/
|
|
PINSEL0 &= 0xF0FFFFFF;
|
|
PINSEL0 |= 0x0A000000;
|
|
PCONP = (PCONP & PCALL) | PCTIM1;
|
|
|
|
/*
|
|
* Timer setup.
|
|
*/
|
|
TC *tc = T1Base;
|
|
StopCounter(tc);
|
|
tc->TC_CTCR = 0; // Clock source is PCLK.
|
|
tc->TC_PR = 0; // Prescaler disabled.
|
|
tc->TC_MCR = 2; // Clear TC on match MR0.
|
|
}
|
|
|
|
static void stop(void *p) {
|
|
TC *tc = T1Base;
|
|
|
|
StopCounter(tc);
|
|
chEvtBroadcastI(&BuzzerSilentEventSource);
|
|
}
|
|
|
|
void PlaySound(int freq, systime_t duration) {
|
|
static VirtualTimer bvt;
|
|
TC *tc = T1Base;
|
|
|
|
chSysLock();
|
|
|
|
if (chVTIsArmedI(&bvt)) { // If a sound is already being played
|
|
chVTResetI(&bvt); // then aborts it.
|
|
StopCounter(tc);
|
|
}
|
|
|
|
tc->TC_MR0 = tc->TC_MR1 = (PCLK / (freq * 2));
|
|
StartCounter(tc);
|
|
chVTSetI(&bvt, duration, stop, NULL);
|
|
|
|
chSysUnlock();
|
|
}
|
|
|
|
void PlaySoundWait(int freq, systime_t duration) {
|
|
TC *tc = T1Base;
|
|
|
|
StopCounter(tc);
|
|
tc->TC_MR0 = tc->TC_MR1 = (PCLK / (freq * 2));
|
|
StartCounter(tc);
|
|
chThdSleep(duration);
|
|
StopCounter(tc);
|
|
}
|