Files
CE2812-Workspace/labW6barnestr/Src/piezoSpeaker.c
2022-02-04 10:14:45 -06:00

110 lines
2.4 KiB
C

/**
* @file piezoSpeaker.c
* @author Trevor Barnes
* @brief Provides functionality for initializing, playing notes, and playing songs on the piezo speaker.
* @version 0.1
* @date 2022-01-12
*
* @copyright Copyright (c) 2022
*
*/
#include <stdio.h>
#include <inttypes.h>
#include "piezoSpeaker.h"
#include "delay.h"
volatile RCC* const rcc = 0x40023800;
volatile GPIO* const gpiob = 0x40020400;
volatile TIM* const tim3 = 0x40000400;
volatile SYSCFG* const syscfg = 0x40013800;
volatile EXTI* const exti4 = 0x40013C00;
void piezo_init(){
// GPIOB/Timer3 enable in RCC
(*rcc).AHB1ENR |= (1<<GPIOBEN);
(*rcc).APB1ENR |= (1<<TIM3_EN);
// Set to "alternate function" mode
(*gpiob).MODER = ((*gpiob).MODER&~(0b11<<8)) | (PB4_AF_V<<8);
// Set AF to low
(*gpiob).AFRL |= (1<<AFRL_TIM3_CH1_EN);
// Set to output capture
(*tim3).CCMR1 |= OC1M_PWM2;
(*tim3).CCMR1 |= (1<<OC1PE);
(*tim3).CCER |= CCER_CC1E;
// Enable Preload
(*tim3).CR1 |= (1<<CR_ARPE_EN);
}
void play_note(Note noteToPlay) {
(*tim3).PSC = 15;
// Pitch divisor to scale with timer
(*tim3).ARR = (pitchDivisor)/(noteToPlay.noteFrequency);
// Volume (Smaller dividend = louder sound)
unsigned int freq = (noteToPlay.noteFrequency/10);
// Clear CCR
(*tim3).CCR1 = ((*tim3).CCR1&~(0xFFFF));
(*tim3).CCR1 = freq;
// Set EGR
(*tim3).EGR |= EGR_UG;
// Playing note
// Enables timer
(*tim3).CR1 |= 1;
// Delay for duration of note
delay_1ms(noteToPlay.noteDuration);
// Disables timer
(*tim3).CR1 &= ~1;
}
void play_song(Note *songToPlay){
int i = 0;
// Iterate through song and play each note till "END" value
while(songToPlay[i].noteFrequency != END) {
play_note(songToPlay[i]);
i++;
}
}
void play_note_br(Note noteToplay) {
}
void TIM3_IRQHandler(void) {
(*tim3).PSC = 15;
// Pitch divisor to scale with timer
(*tim3).ARR = (pitchDivisor)/(noteToPlay.noteFrequency);
// Volume (Smaller dividend = louder sound)
unsigned int freq = (noteToPlay.noteFrequency/10);
// Clear CCR
(*tim3).CCR1 = ((*tim3).CCR1&~(0xFFFF));
(*tim3).CCR1 = freq;
// Set EGR
(*tim3).EGR |= EGR_UG;
// Playing note
// Enables timer
(*tim3).CR1 |= 1;
// Delay for duration of note
// This is gonna have to change
delay_1ms(noteToPlay.noteDuration);
// Disables timer
(*tim3).CR1 &= ~1;
}
void play_song_br(Note *songToPlay) {
// PB4 Connected to EXTI4
(*syscfg).EXTICR2 &= ~(0xF);
(*syscfg).EXTICR2 &= ~(0x1);
}