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aprs_pico_send1kHz() -> aprs_pico_send_sine_wave(); renamings

main
eleccoder 2022-12-21 18:13:43 +01:00
rodzic 4a97c15181
commit 525671c31e
1 zmienionych plików z 26 dodań i 23 usunięć
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49
src/aprs_pico.c
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@ -108,7 +108,7 @@ static void aprs_pico_initClock(unsigned int sample_freq_in_hz)
* \param[in] pcm_data The PCM audio samples to be rendered
* \param[in] num_samples The number of PCM audio samples to be rendered
* \param[in] volume The volume level of the generated AFSK signal (0 ... 256)
* \param[in] is_loop_forever If 'true', the rendering of the audio samples will be continuously repeated
* \param[in] is_loop_forever If 'true', rendering of the audio samples will be continuously repeated
*/
static void aprs_pico_renderAudioSamples(audio_buffer_pool_t* audio_buffer_pool, const int16_t* pcm_data,
unsigned int num_samples, uint16_t volume, bool is_loop_forever)
@ -116,24 +116,25 @@ static void aprs_pico_renderAudioSamples(audio_buffer_pool_t* audio_buffer_pool,
assert(audio_buffer_pool != NULL);
assert(pcm_data != NULL);
unsigned int pos = 0u;
bool is_keep_going = true;
unsigned int idx_src = 0u;
bool is_keep_going = true;
// Write the PCM sample data into the audio buffer(s) while applying the 'volume' value
while (is_keep_going)
{
audio_buffer_t* buffer = take_audio_buffer(audio_buffer_pool, true);
int16_t* samples = (int16_t*)buffer->buffer->bytes;
audio_buffer_t* audio_buffer = take_audio_buffer(audio_buffer_pool, true);
int16_t* audio_buffer_pcm_data = (int16_t*)audio_buffer->buffer->bytes;
for (unsigned int i = 0u; i < buffer->max_sample_count; i++)
for (unsigned int idx_dst = 0u; idx_dst < audio_buffer->max_sample_count; idx_dst++)
{
samples[i] = ((int32_t)volume * (int32_t)pcm_data[pos]) >> 8u;
pos++;
audio_buffer_pcm_data[idx_dst] = ((int32_t)volume * (int32_t)pcm_data[idx_src]) >> 8u;
idx_src++;
if (pos == num_samples)
if (idx_src == num_samples)
{
if (is_loop_forever)
{
pos = 0u;
idx_src = 0u;
}
else
{
@ -143,8 +144,8 @@ static void aprs_pico_renderAudioSamples(audio_buffer_pool_t* audio_buffer_pool,
}
}
buffer->sample_count = buffer->max_sample_count;
give_audio_buffer(audio_buffer_pool, buffer);
audio_buffer->sample_count = audio_buffer->max_sample_count;
give_audio_buffer(audio_buffer_pool, audio_buffer);
}
}
@ -176,34 +177,36 @@ audio_buffer_pool_t* aprs_pico_init()
// See the header file for documentation
void aprs_pico_send1kHz(audio_buffer_pool_t* audio_buffer_pool, uint16_t volume)
void aprs_pico_send_sine_wave(audio_buffer_pool_t* audio_buffer_pool, unsigned int freq_in_hz, uint16_t volume)
{
assert(audio_buffer_pool != NULL);
// WARNING: ATTOW, the pico audio PWM lib worked only @ 22050 Hz sampling frequency and 48 MHz system clock
// This is documented here: https://github.com/raspberrypi/pico-extras
unsigned int sample_freq_in_hz = APRS_PICO__PICO_EXTRA_AUDIO_PWM_LIB_FIXED_SAMPLE_FREQ_IN_HZ;
const unsigned int SAMPLE_FREQ_IN_HZ = APRS_PICO__PICO_EXTRA_AUDIO_PWM_LIB_FIXED_SAMPLE_FREQ_IN_HZ;
const unsigned int num_samples_per_period = SAMPLE_FREQ_IN_HZ / freq_in_hz;
aprs_pico_initClock(sample_freq_in_hz);
typedef int16_t wave_table_value_t;
const wave_table_value_t WAVE_TABLE_VALUE_MAX = INT16_MAX;
const unsigned int TONE_FREQ_IN_HZ = 1000u;
const unsigned int num_samples = sample_freq_in_hz / TONE_FREQ_IN_HZ;
int16_t* sine_wave_table = malloc(num_samples * sizeof(int16_t));
aprs_pico_initClock(SAMPLE_FREQ_IN_HZ);
if (!sine_wave_table)
wave_table_value_t* sine_period_wave_table = malloc(num_samples_per_period * sizeof(wave_table_value_t));
if (sine_period_wave_table == NULL)
{
panic("Out of memory: malloc() failed.\n");
}
for (unsigned int i = 0u; i < num_samples; i++)
for (unsigned int i = 0u; i < num_samples_per_period; i++)
{
sine_wave_table[i] = (int16_t)(32767.0f * sinf(2.0f * (float)M_PI * (float)i / (float)num_samples));
sine_period_wave_table[i] = (wave_table_value_t)((float)WAVE_TABLE_VALUE_MAX * sinf(2.0f * (float)M_PI * (float)i / (float)num_samples_per_period));
}
aprs_pico_renderAudioSamples(audio_buffer_pool, sine_wave_table, num_samples, volume, true);
aprs_pico_renderAudioSamples(audio_buffer_pool, sine_period_wave_table, num_samples_per_period, volume, true);
free(sine_wave_table);
free(sine_period_wave_table);
}