blob: e18891032ae8ad9fea3edaf964cee78fcbc86336 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
|
// Playback example with the USBAUDIO library
#include "mbed.h"
#include "USBAudio.h"
// frequency: 48 kHz
#define FREQ_SPK 48000
#define FREQ_MIC 48000
// 2channels: stereo
#define NB_CHA_SPK 2
#define NB_CHA_MIC 2
// length computed: each ms, we receive 48 * 16bits ->48 * 2 bytes. as there are two channels, the length will be 48 * 2 * 2
#define LENGTH_AUDIO_PACKET_SPK (FREQ_SPK / 500) * NB_CHA_SPK
#define LENGTH_AUDIO_PACKET_MIC (FREQ_MIC / 500) * NB_CHA_MIC
// USBAudio object
USBAudio audio(FREQ_SPK, NB_CHA_SPK, FREQ_MIC, NB_CHA_MIC, 0xab45, 0x0378);
int main() {
// buffer of int
int buf_in[LENGTH_AUDIO_PACKET_SPK/sizeof(int)];
int buf_out[LENGTH_AUDIO_PACKET_MIC/sizeof(int)];
int * stream_out = buf_in;
int * stream_in = buf_out;
int * tmp = NULL;
while (1) {
// read and write one audio packet each frame
audio.readWrite((uint8_t *)stream_in, (uint8_t *)stream_out);
// swap the buffers
tmp = stream_in;
stream_in = stream_out;
stream_out = tmp;
}
}
|
