ST / Mbed 2 deprecated HelloWorld_CCA01M1

Simple test application for the STMicroelectronics X-NUCLEO-CCA01M1 Sound Terminal Expansion Board, built against mbed classic.

Dependencies:   X_NUCLEO_CCA01M1 ST_Events-old mbed

Fork of HelloWorld_CCA01M1_mbedOS by ST

Playing audio with the X-NUCLEO-CCA01M1 Expansion Board

This application provides a simple example of usage of the X-NUCLEO-CCA01M1 Sound Terminal Expansion Board, built against mbed classic.

It shows how to play a 2-channel stereo signal stored in an array of PCM samples directly on the speakers connected to the expansion board.

It also allows to stop/play the audio by pressing the user button on the Nucleo board.


Platform compatibility

  • This board can be currently used with a Nucleo-F401RE board only and has been tested with the default configuration provided by this example.
  • Please note that the main application makes use of the "events" library, which is not included into the "mbed" library.
  • The application built against mbed OS 5.x can be found here.

Diff: main.cpp

Revision:
9:34ebb3f5a2ad
Parent:
7:94e3191477c5
--- a/main.cpp	Wed May 03 16:32:32 2017 +0000
+++ b/main.cpp	Mon May 15 15:51:10 2017 +0000
@@ -41,7 +41,6 @@
 
 /* mbed specific header files. */
 #include "mbed.h"
-#include "rtos.h"
 
 
 #if DEVICE_I2S
@@ -74,54 +73,10 @@
 /* Sound Terminal Component. */
 STA350BW *sound_terminal;
 
-/* Thread to manage I2S peripherals. */
-static rtos::Thread i2s_bh_daemon;
-
-/* Threads. */
-Thread *play_stop_thread;
-
-/* User button handling. */
-InterruptIn event(USER_BUTTON);
-
 
 /* Functions -----------------------------------------------------------------*/
 
 /**
- * @brief  User button handler function.
- * @param  None.
- * @retval None.
- */
-void pressed(void)
-{
-    /* Signal to play/stop handler thread. */
-    play_stop_thread->signal_set(PLAY_STOP_EVENT);
-}
-
-/**
- * @brief  Play/stop handler function.
- * @param  None.
- * @retval None.
- */
-void play_stop_handler(void)
-{
-    while (true)
-    {
-        static bool stop = true;
-
-        /* Waiting for play/stop events. */
-        play_stop_thread->signal_wait(PLAY_STOP_EVENT);
-
-        if (stop)
-            sound_terminal->stop();
-        else
-            sound_terminal->play((int16_t *) my_song, (uint16_t) sizeof(my_song), true);
-        printf("--> %s\r\n", stop ? "Stop." : "Playing...");
-
-        stop = !stop;
-    }
-}
-
-/**
  * @brief  Entry point function of mbedOS.
  * @param  None
  * @retval None
@@ -145,17 +100,6 @@
         exit(EXIT_FAILURE);
     }
 
-    /* Starting a thread to manage I2S peripherals. */
-    Callback<void()> i2s_bh_task(&I2S::i2s_bh_queue, &events::EventQueue::dispatch_forever);
-    i2s_bh_daemon.start(i2s_bh_task);
-
-    /* Scheduling the play/stop function. */
-    play_stop_thread = new Thread();
-    osStatus status = play_stop_thread->start(play_stop_handler);
-    if (status != osOK)
-        printf("Could not start the play/stop handler thread.\r\n");
-    event.fall(&pressed);
-
     /* Setting Sound Terminal Component's parameters. */
     sound_terminal->set_frequency(MY_SONG_AUDIO_FREQUENCY);
     sound_terminal->set_volume(STA350BW_CHANNEL_MASTER, 60);
@@ -169,6 +113,9 @@
     /* Printing to the console. */
     printf("--> Playing...\r\n");
     sound_terminal->play((int16_t *) my_song, (uint16_t) sizeof(my_song), true);
+
+    /* Dispatching forever the I2S queue. */
+    I2S::i2s_bh_queue.dispatch_forever();
 }
 
 #else // DEVICE_I2S