Samuel Mokrani / Mbed 2 deprecated USBAudioPlayback

USBAudio example: playback

Dependencies:   mbed USBDevice

main.cpp@2:6d4dcaa2c065, 2013-03-01 (annotated)

Committer:
samux
Date:
Fri Mar 01 13:22:17 2013 +0000
Revision:
2:6d4dcaa2c065
Parent:
0:eb53799c0b97 
use latest USBDevice lib (FRDM-KL25Z support)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
samux 0:eb53799c0b97 1 // Playback example with the USBAUDIO library
samux 0:eb53799c0b97 2
samux 0:eb53799c0b97 3 #include "mbed.h"
samux 0:eb53799c0b97 4 #include "USBAudio.h"
samux 0:eb53799c0b97 5
samux 0:eb53799c0b97 6 // frequency: 48 kHz
samux 0:eb53799c0b97 7 #define FREQ_SPK 48000
samux 0:eb53799c0b97 8 #define FREQ_MIC 48000
samux 0:eb53799c0b97 9
samux 0:eb53799c0b97 10 // 2channels: stereo
samux 0:eb53799c0b97 11 #define NB_CHA_SPK 2
samux 0:eb53799c0b97 12 #define NB_CHA_MIC 2
samux 0:eb53799c0b97 13
samux 0:eb53799c0b97 14 // length computed: each ms, we receive 48 * 16bits ->48 * 2 bytes. as there are two channels, the length will be 48 * 2 * 2
samux 0:eb53799c0b97 15 #define LENGTH_AUDIO_PACKET_SPK (FREQ_SPK / 500) * NB_CHA_SPK
samux 0:eb53799c0b97 16 #define LENGTH_AUDIO_PACKET_MIC (FREQ_MIC / 500) * NB_CHA_MIC
samux 0:eb53799c0b97 17
samux 0:eb53799c0b97 18 // USBAudio object
samux 0:eb53799c0b97 19 USBAudio audio(FREQ_SPK, NB_CHA_SPK, FREQ_MIC, NB_CHA_MIC, 0xab45, 0x0378);
samux 0:eb53799c0b97 20
samux 0:eb53799c0b97 21 int main() {
samux 0:eb53799c0b97 22 // buffer of int
samux 0:eb53799c0b97 23 int buf_in[LENGTH_AUDIO_PACKET_SPK/sizeof(int)];
samux 0:eb53799c0b97 24 int buf_out[LENGTH_AUDIO_PACKET_MIC/sizeof(int)];
samux 0:eb53799c0b97 25 int * stream_out = buf_in;
samux 0:eb53799c0b97 26 int * stream_in = buf_out;
samux 0:eb53799c0b97 27 int * tmp = NULL;
samux 0:eb53799c0b97 28
samux 0:eb53799c0b97 29 while (1) {
samux 0:eb53799c0b97 30 // read and write one audio packet each frame
samux 0:eb53799c0b97 31 audio.readWrite((uint8_t *)stream_in, (uint8_t *)stream_out);
samux 0:eb53799c0b97 32
samux 0:eb53799c0b97 33 // swap the buffers
samux 0:eb53799c0b97 34 tmp = stream_in;
samux 0:eb53799c0b97 35 stream_in = stream_out;
samux 0:eb53799c0b97 36 stream_out = tmp;
samux 0:eb53799c0b97 37 }
samux 0:eb53799c0b97 38 }
samux 0:eb53799c0b97 39
samux 0:eb53799c0b97 40