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Adjust sound volume with select+up/down & add DMG color palette

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This commit is contained in:
Vincent Mistler
2022-12-17 16:37:47 +01:00
parent 0226b24c7b
commit 4a0516a7ae
5 changed files with 166 additions and 62 deletions
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ext/i2s/i2s.c
+64 -9
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@@ -24,6 +24,9 @@
#include "i2s.h"
/**
* return the default i2s context used to store information about the setup
*/
i2s_config_t i2s_get_default_config(void) {
i2s_config_t i2s_config = {
.sample_freq = 44100,
@@ -35,11 +38,16 @@ i2s_config_t i2s_get_default_config(void) {
.dma_channel = 0,
.dma_buf = NULL,
.dma_trans_count = 0,
.volume = 0,
};
return i2s_config;
}
/**
* Initialize the I2S driver. Must be called before calling i2s_write or i2s_dma_write
* i2s_config: I2S context obtained by i2s_get_default_config()
*/
void i2s_init(i2s_config_t *i2s_config) {
uint8_t func=GPIO_FUNC_PIO0; // TODO: GPIO_FUNC_PIO0 for pio0 or GPIO_FUNC_PIO1 for pio1
gpio_set_function(i2s_config->data_pin, GPIO_FUNC_PIO0);
@@ -52,17 +60,17 @@ void i2s_init(i2s_config_t *i2s_config) {
audio_i2s_program_init(i2s_config->pio, i2s_config->sm , offset, i2s_config->data_pin , i2s_config->clock_pin_base);
// Set PIO clock
/* Set PIO clock */
uint32_t system_clock_frequency = clock_get_hz(clk_sys);
uint32_t divider = system_clock_frequency * 4 / i2s_config->sample_freq; // avoid arithmetic overflow
pio_sm_set_clkdiv_int_frac(i2s_config->pio, i2s_config->sm , divider >> 8u, divider & 0xffu);
pio_sm_set_enabled(i2s_config->pio, i2s_config->sm, false);
// Allocate memory for the DMA buffer
/* Allocate memory for the DMA buffer */
i2s_config->dma_buf=malloc(i2s_config->dma_trans_count*sizeof(uint32_t));
// Direct Memory Access setup
/* Direct Memory Access setup */
i2s_config->dma_channel = dma_claim_unused_channel(true);
dma_channel_config dma_config = dma_channel_get_default_config(i2s_config->dma_channel);
@@ -81,20 +89,67 @@ void i2s_init(i2s_config_t *i2s_config) {
pio_sm_set_enabled(i2s_config->pio, i2s_config->sm , true);
}
/**
* Write samples to I2S directly and wait for completion (blocking)
* i2s_config: I2S context obtained by i2s_get_default_config()
* sample: pointer to an array of len x 32 bits samples
* Each 32 bits sample contains 2x16 bits samples,
* one for the left channel and one for the right channel
* len: length of sample in 32 bits words
*/
void i2s_write(const i2s_config_t *i2s_config,const int16_t *samples,const size_t len) {
for(size_t i=0;i<len;i++) {
for(size_t i=0;i<len;i+=2) {
pio_sm_put_blocking(i2s_config->pio, i2s_config->sm, (uint32_t)samples[i]);
}
}
// Write samples to DMA buffer and initiate DMA transfer (non blocking)
/**
* Write samples to DMA buffer and initiate DMA transfer (non blocking)
* i2s_config: I2S context obtained by i2s_get_default_config()
* sample: pointer to an array of dma_trans_count x 32 bits samples
*/
void i2s_dma_write(i2s_config_t *i2s_config,const int16_t *samples) {
// Wait the completion of the previous DMA transfer
/* Wait the completion of the previous DMA transfer */
dma_channel_wait_for_finish_blocking(i2s_config->dma_channel);
// Copy samples into the DMA buffer
memcpy(i2s_config->dma_buf,samples,i2s_config->dma_trans_count*sizeof(int32_t));
// Initiate the DMA transfer
/* Copy samples into the DMA buffer */
if(i2s_config->volume==0) {
memcpy(i2s_config->dma_buf,samples,i2s_config->dma_trans_count*sizeof(int32_t));
} else {
for(uint16_t i=0;i<i2s_config->dma_trans_count*2;i++) {
i2s_config->dma_buf[i] = samples[i]>>i2s_config->volume;
}
}
/* Initiate the DMA transfer */
dma_channel_transfer_from_buffer_now(i2s_config->dma_channel,
i2s_config->dma_buf,
i2s_config->dma_trans_count);
}
/**
* Adjust the output volume
* i2s_config: I2S context obtained by i2s_get_default_config()
* volume: desired volume between 0 (highest. volume) and 16 (lowest volume)
*/
void i2s_volume(i2s_config_t *i2s_config,uint8_t volume) {
if(volume>16) volume=16;
i2s_config->volume=volume;
}
/**
* Increases the output volume
*/
void i2s_increase_volume(i2s_config_t *i2s_config) {
if(i2s_config->volume>0) {
i2s_config->volume--;
}
}
/**
* Decreases the output volume
*/
void i2s_decrease_volume(i2s_config_t *i2s_config) {
if(i2s_config->volume<16) {
i2s_config->volume++;
}
}