boop/boop/infrared/pwm.c
2017-07-16 20:42:08 +02:00

82 lines
1.8 KiB
C

/*
pwm.c - pwm control
Copyright (C) 2017 <telekatz@gmx.de>
This program 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.
This program 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/>.
*/
#include "global.h"
#include "lpc2220.h"
#include "irq.h"
void PWM_init(void)
{
//Set pin P0.21 IR_OUT as PWM
PINSEL1 &= ~(3 << (10)); // IO
PINSEL1 |= (1 << (10)); // PWM5
PWMTC = 0; //Timer Counter
PWMPR = 0; //Prescale Register
PWMPC = 0; //Prescale Counter
PWMMR0 = 416; // pwm rate
PWMMR2 = 0x00; // pwm value sound
PWMMR5 = 0x00; // pwm value IR
PWMLER = 0x26; //Latch Enable
PWMMCR = 0x03; //Match Control
PWMPCR |= (1<<13) | (1<<10);
PWMTCR = 0x03;
PWMTCR = 0x09;
/* PWMTC = 0;
PWMPR = 7;
PWMMR0 = 0x1E6; // pwm rate
PWMMR2 = 0x00; // pwm value
PWMLER = 0x05;
PWMPCR = (1<<10);
*/
//VICVectAddr0 = (unsigned long)&(soundIRQ);
//VICVectCntl0 = VIC_SLOT_EN | INT_SRC_PWM;
VICIntSelect |= INT_PWM;
VICIntEnable = INT_PWM;
}
void PWM_set_frequency(unsigned long f)
{
if(f<5000) {
PWMPR = 7;
PWMMR0 = 1875000 / f;
} else {
PWMPR = 0;
PWMMR0 = 15000000 / f;
}
PWMLER |= 0x01; //Latch Enable
if(f < 32000) {
PWMMCR = 0x03;
} else {
PWMMCR = 0x02;
}
}
void PWM_set_IR_duty_cycle(unsigned char d) {
PWMMR5 = (PWMMR0 * d) / 100;
PWMLER |= 0x20;
}