1+
2+ #pragma once
3+
4+ #include " AudioConfig.h"
5+ #if defined(IS_MBED) && defined(USE_I2S_ANALOG)
6+
7+ #
if __has_include && !__has_include(<Arduino_AdvancedAnalog.h>)
8+ #error "Please install the Arduino_AdvancedAnalog library"
9+ #else
10+
11+ #include < Arduino_AdvancedAnalog.h>
12+ // #include <pins_arduino.h>
13+
14+ namespace audio_tools {
15+
16+ /* *
17+ * @brief Please use AnalogAudioStream: A ADC and DAC API for the Arduino Giga.
18+ * @ingroup platform
19+ * @author Phil Schatzmann
20+ * @copyright GPLv3
21+ */
22+
23+ class AnalogDriverMBED : public AnalogDriverBase {
24+ public:
25+ // / Default constructor
26+ AnalogDriverMBED () = default ;
27+
28+ // / Destructor
29+ virtual ~AnalogDriverMBED () { end (); }
30+
31+ // / starts the DAC
32+ bool begin (AnalogConfig cfg) {
33+ TRACEI ();
34+ if (cfg.bits_per_sample != 16 ) {
35+ LOGE (" Only 16 bits_per_sample supported"
36+ return false ;
37+ }
38+ if (cfg.channels > 2 ) {
39+ LOGE (" max channels: 2"
40+ return false ;
41+ }
42+ if (cfg.channels <= 0 ) {
43+ LOGE (" no channels"
44+ return false ;
45+ }
46+ info = cfg;
47+ int n_samples = cfg.buffer_size / (cfg.bits_per_sample / 8 );
48+ ring_buffer.resize (n_samples);
49+ switch (info.channels ) {
50+ case 1 :
51+ dac1.begin (AN_RESOLUTION_12, info.sample_rate , n_samples,
52+ cfg.buffer_count );
53+ break ;
54+ case 2 :
55+ dac1.begin (AN_RESOLUTION_12, info.sample_rate , n_samples / 2 ,
56+ cfg.buffer_count );
57+ dac2.begin (AN_RESOLUTION_12, info.sample_rate , n_samples / 2 ,
58+ cfg.buffer_count );
59+ break ;
60+ }
61+ return true ;
62+ }
63+
64+ // / stops the I2S and unistalls the driver
65+ void end () override {
66+ active = false ;
67+ dac1.stop ();
68+ dac2.stop ();
69+ adc1.stop ();
70+ adc2.stop ();
71+ }
72+
73+ int availableForWrite () {
74+ return dac1.available () ? info.buffer_size : 0 ;
75+ }
76+
77+ // / writes the data to the I2S interface
78+ size_t write (const uint8_t *src, size_t size_bytes) override {
79+ TRACED ();
80+ if (!dac1.available ())
81+ return 0 ;
82+
83+ // collect data in ringbuffer
84+ size_t result = 0 ;
85+ int sample_count = size_bytes / 2 ;
86+ Sample *data = (Sample *)src;
87+ for (int j = 0 ; j < sample_count; j++) {
88+ ring_buffer.write (data[j]);
89+ // process ringbuffer when it is full
90+ if (ring_buffer.isFull ()) {
91+ result += writeBuffer ();
92+ }
93+ }
94+ return result;
95+ }
96+
97+ void flush () {
98+ const int size = info.buffer_size ;
99+ const uint8_t data[size] = {0 };
100+ write (data, size);
101+ ring_buffer.reset ();
102+ }
103+
104+ size_t readBytes (uint8_t *dest, size_t size_bytes) override {
105+ TRACED ();
106+ size_t result = 0 ;
107+ int16_t *data = (int16_t *)dest;
108+ size_t samples = size_bytes / 2 ;
109+ switch (info.channels ) {
110+ case 1 :
111+ for (int j = 0 ; j < samples; j++) {
112+ data[j] = adc1.read ();
113+ result += 2 ;
114+ }
115+ break ;
116+ case 2 :
117+ for (int j = 0 ; j < samples; j += 2 ) {
118+ data[j] = adc1.read ();
119+ data[j + 1 ] = adc2.read ();
120+ result += 4 ;
121+ }
122+ break ;
123+ }
124+ return result;
125+ }
126+
127+ virtual int available () override { return info.buffer_size ; }
128+
129+ protected:
130+ RingBuffer<Sample> ring_buffer{0 };
131+ AnalogConfig info;
132+ AdvancedDAC dac1{PIN_DAC_1};
133+ AdvancedDAC dac2{PIN_DAC_2};
134+ AdvancedADC adc1{PIN_ADC_START};
135+ AdvancedADC adc2{PIN_ADC_START + 1 };
136+ bool active = false ;
137+
138+ // / The ringbuffer is used to make sure that we can write full SampleBuffers
139+ size_t writeBuffer () {
140+ size_t result = 0 ;
141+ switch (info.channels ) {
142+ case 1 : {
143+ SampleBuffer buf = dac1.dequeue ();
144+ for (size_t i = 0 ; i < buf.size (); i++) {
145+ buf[i] = ring_buffer.read ();
146+ result += 2 ;
147+ }
148+ dac1.write (buf);
149+ } break ;
150+ case 2 : {
151+ SampleBuffer buf1 = dac1.dequeue ();
152+ SampleBuffer buf2 = dac2.dequeue ();
153+ for (size_t i = 0 ; i < buf1.size (); i += 2 ) {
154+ buf1[i] = ring_buffer.read ();
155+ buf2[i] = ring_buffer.read ();
156+ result += 4 ;
157+ }
158+ dac1.write (buf1);
159+ dac2.write (buf2);
160+ } break ;
161+ }
162+ assert (ring_buffer.isEmpty ());
163+ return result;
164+ }
165+ };
166+
167+ // / @brief AnalogAudioStream
168+ using AnalogDriver = AnalogDriverMBED;
169+
170+ } // namespace audio_tools
171+
172+ #endif // __has_include
173+ #endif // USE_I2S_ANALOG
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