1+ #include "dtmf_dolphin_audio.h"
2+
3+ DTMFDolphinAudio * current_player ;
4+
5+ static void dtmf_dolphin_audio_dma_isr (void * ctx ) {
6+ FuriMessageQueue * event_queue = ctx ;
7+
8+ if (LL_DMA_IsActiveFlag_HT1 (DMA1 )) {
9+ LL_DMA_ClearFlag_HT1 (DMA1 );
10+
11+ DTMFDolphinCustomEvent event = {.type = DTMFDolphinEventDMAHalfTransfer };
12+ furi_message_queue_put (event_queue , & event , 0 );
13+ }
14+
15+ if (LL_DMA_IsActiveFlag_TC1 (DMA1 )) {
16+ LL_DMA_ClearFlag_TC1 (DMA1 );
17+
18+ DTMFDolphinCustomEvent event = {.type = DTMFDolphinEventDMAFullTransfer };
19+ furi_message_queue_put (event_queue , & event , 0 );
20+ }
21+ }
22+
23+ void dtmf_dolphin_audio_clear_samples (DTMFDolphinAudio * player ) {
24+ for (size_t i = 0 ; i < player -> buffer_length ; i ++ ) {
25+ player -> sample_buffer [i ] = 0 ;
26+ }
27+ }
28+
29+ DTMFDolphinOsc * dtmf_dolphin_osc_alloc () {
30+ DTMFDolphinOsc * osc = { 0 };
31+ osc -> cached_freq = 0 ;
32+ osc -> offset = 0 ;
33+ osc -> period = 0 ;
34+ return osc ;
35+ }
36+
37+ DTMFDolphinAudio * dtmf_dolphin_audio_alloc () {
38+ DTMFDolphinAudio player ;
39+ player .buffer_length = SAMPLE_BUFFER_LENGTH ;
40+ player .half_buffer_length = SAMPLE_BUFFER_LENGTH / 2 ;
41+ player .buffer_buffer = malloc (sizeof (uint8_t ) * player .buffer_length );
42+ player .sample_buffer = malloc (sizeof (uint16_t ) * player .buffer_length );
43+ player .osc1 = dtmf_dolphin_osc_alloc ();
44+ player .osc2 = dtmf_dolphin_osc_alloc ();
45+ player .playing = false;
46+ player .volume = 2.0f ;
47+ player .queue = furi_message_queue_alloc (10 , sizeof (DTMFDolphinCustomEvent ));
48+ dtmf_dolphin_audio_clear_samples (& player );
49+
50+ return false;
51+ }
52+
53+ size_t calc_waveform_period (float freq ) {
54+ if (!freq ) {
55+ return 0 ;
56+ }
57+ // DMA Rate constant, thanks to Dr_Zlo
58+ float dma_rate = CPU_CLOCK_FREQ \
59+ / 2 \
60+ / DTMF_DOLPHIN_HAL_DMA_PRESCALER \
61+ / (DTMF_DOLPHIN_HAL_DMA_AUTORELOAD + 1 );
62+
63+ return (uint16_t ) (dma_rate / freq );
64+ }
65+
66+ float sample_frame (DTMFDolphinOsc * osc , float freq ) {
67+ float frame = 0.0 ;
68+
69+ if (freq != osc -> cached_freq || !osc -> period ) {
70+ osc -> cached_freq = freq ;
71+ osc -> period = calc_waveform_period (freq );
72+ osc -> offset = 0 ;
73+ }
74+ if (osc -> period ) {
75+ frame = tanhf (sin (osc -> offset * PERIOD_2_PI / osc -> period ) + 1 );
76+ osc -> offset = (osc -> offset + 1 ) % osc -> period ;
77+ }
78+
79+ return frame ;
80+ }
81+
82+ void dtmf_dolphin_audio_free (DTMFDolphinAudio * player ) {
83+ furi_message_queue_free (player -> queue );
84+ dtmf_dolphin_osc_free (player -> osc1 );
85+ dtmf_dolphin_osc_free (player -> osc2 );
86+ free (player -> buffer_buffer );
87+ free (player -> sample_buffer );
88+ }
89+
90+ void dtmf_dolphin_osc_free (DTMFDolphinOsc * osc ) {
91+ UNUSED (osc );
92+ // Nothing to free now, but keeping this here in case I reimplement caching
93+ }
94+
95+ bool generate_waveform (DTMFDolphinAudio * player , float freq1 , float freq2 , uint16_t buffer_index ) {
96+ uint16_t * sample_buffer_start = & player -> sample_buffer [buffer_index ];
97+
98+ for (size_t i = 0 ; i < player -> half_buffer_length ; i ++ ) {
99+ float data = (sample_frame (player -> osc1 , freq1 ) / 2 ) + (sample_frame (player -> osc2 , freq2 ) / 2 );
100+ data *= player -> volume ;
101+ data *= UINT8_MAX / 2 ; // scale -128..127
102+ data += UINT8_MAX / 2 ; // to unsigned
103+
104+ if (data < 0 ) {
105+ data = 0 ;
106+ }
107+
108+ if (data > 255 ) {
109+ data = 255 ;
110+ }
111+
112+ player -> buffer_buffer [i ] = data ;
113+ sample_buffer_start [i ] = data ;
114+ }
115+
116+ return true;
117+ }
118+
119+ bool dtmf_dolphin_audio_play_tones (float freq1 , float freq2 ) {
120+ current_player = dtmf_dolphin_audio_alloc ();
121+
122+ generate_waveform (current_player , freq1 , freq2 , 0 );
123+ generate_waveform (current_player , freq1 , freq2 , current_player -> half_buffer_length );
124+
125+ dtmf_dolphin_speaker_init ();
126+ dtmf_dolphin_dma_init ((uint32_t )current_player -> sample_buffer , current_player -> buffer_length );
127+
128+ furi_hal_interrupt_set_isr (FuriHalInterruptIdDma1Ch1 , dtmf_dolphin_audio_dma_isr , current_player -> queue );
129+
130+ dtmf_dolphin_dma_start ();
131+ dtmf_dolphin_speaker_start ();
132+
133+ return true;
134+ }
135+
136+ bool dtmf_dolphin_audio_stop_tones () {
137+ current_player -> playing = false;
138+
139+ dtmf_dolphin_speaker_stop ();
140+ dtmf_dolphin_dma_stop ();
141+
142+ furi_hal_interrupt_set_isr (FuriHalInterruptIdDma1Ch1 , NULL , NULL );
143+
144+ dtmf_dolphin_audio_free (current_player );
145+
146+ return true;
147+ }
148+
149+ bool dtmf_dolphin_audio_handle_tick () {
150+ DTMFDolphinCustomEvent event ;
151+
152+ if (furi_message_queue_get (current_player -> queue , & event , FuriWaitForever ) == FuriStatusOk ) {
153+ if (event .type == DTMFDolphinEventDMAHalfTransfer ) {
154+ generate_waveform (
155+ current_player ,
156+ (double ) current_player -> osc1 -> cached_freq ,
157+ (double ) current_player -> osc2 -> cached_freq ,
158+ 0 );
159+ return true;
160+ } else if (event .type == DTMFDolphinEventDMAFullTransfer ) {
161+ generate_waveform (
162+ current_player ,
163+ (double ) current_player -> osc1 -> cached_freq ,
164+ (double ) current_player -> osc2 -> cached_freq ,
165+ current_player -> half_buffer_length );
166+ return true;
167+ }
168+ }
169+ return false;
170+ }
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