Changed AudioInput and AudioOutput demos to reload the next sample via an interrupt...

[pub/USBasp.git] / Demos / Device / LowLevel / AudioInput / AudioInput.c

diff --git a/Demos/Device/LowLevel/AudioInput/AudioInput.c b/Demos/Device/LowLevel/AudioInput/AudioInput.c
index 8e2d974..9257806 100644 (file)
--- a/Demos/Device/LowLevel/AudioInput/AudioInput.c
+++ b/Demos/Device/LowLevel/AudioInput/AudioInput.c
@@ -51,7 +51,6 @@ int main(void)
 
        for (;;)
        {
-               USB_Audio_Task();
                USB_USBTask();
        }
 }
@@ -86,6 +85,7 @@ void EVENT_USB_Device_Connect(void)
        LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 
        /* Sample reload timer initialization */
+       TIMSK0  = (1 << OCIE0A);
        OCR0A   = (F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1;
        TCCR0A  = (1 << WGM01);  // CTC mode
        TCCR0B  = (1 << CS01);   // Fcpu/8 speed
@@ -145,26 +145,17 @@ void EVENT_USB_Device_UnhandledControlRequest(void)
        }
 }
 
-/** Task to manage the Audio interface, reading in ADC samples from the microphone, and them to the host. */
-void USB_Audio_Task(void)
+/** ISR to handle the reloading of the data endpoint with the next sample. */
+ISR(TIMER0_COMPA_vect, ISR_BLOCK)
 {
-       /* Device must be connected and configured for the task to run */
-       if (USB_DeviceState != DEVICE_STATE_Configured)
-         return;
-
-       /* Check to see if the streaming interface is selected, if not the host is not receiving audio */
-       if (!(StreamingAudioInterfaceSelected))
-         return;
+       uint8_t PrevEndpoint = Endpoint_GetCurrentEndpoint();
 
        /* Select the audio stream endpoint */
        Endpoint_SelectEndpoint(AUDIO_STREAM_EPNUM);
 
-       /* Check if the current endpoint can be written to and that the next sample should be stored */
-       if (Endpoint_IsINReady() && (TIFR0 & (1 << OCF0A)))
+       /* Check if the current endpoint can be written to and that the audio interface is enabled */
+       if (Endpoint_IsINReady() && StreamingAudioInterfaceSelected)
        {
-               /* Clear the sample reload timer */
-               TIFR0 |= (1 << OCF0A);
-
                int16_t AudioSample;
 
                #if defined(USE_TEST_TONE)
@@ -197,5 +188,7 @@ void USB_Audio_Task(void)
                        Endpoint_ClearIN();
                }
        }
+
+       Endpoint_SelectEndpoint(PrevEndpoint);
 }