Documentation improvements - put driver example code into its own section, fix incorr...

[pub/USBasp.git] / Demos / Device / ClassDriver / AudioOutput / AudioOutput.c

diff --git a/Demos/Device/ClassDriver/AudioOutput/AudioOutput.c b/Demos/Device/ClassDriver/AudioOutput/AudioOutput.c
index 33b52a1..4650cd8 100644 (file)
--- a/Demos/Device/ClassDriver/AudioOutput/AudioOutput.c
+++ b/Demos/Device/ClassDriver/AudioOutput/AudioOutput.c
@@ -3,7 +3,7 @@
      Copyright (C) Dean Camera, 2010.
 
   dean [at] fourwalledcubicle [dot] com
      Copyright (C) Dean Camera, 2010.
 
   dean [at] fourwalledcubicle [dot] com

-      www.fourwalledcubicle.com
+           www.lufa-lib.org

 */
 
 /*
 */
 
 /*


@@ -63,8 +63,6 @@ int main(void)
 
        for (;;)
        {
 
        for (;;)
        {

-               ProcessNextSample();
-

                Audio_Device_USBTask(&Speaker_Audio_Interface);
                USB_USBTask();
        }
                Audio_Device_USBTask(&Speaker_Audio_Interface);
                USB_USBTask();
        }


@@ -85,35 +83,31 @@ void SetupHardware(void)
        USB_Init();
 }
 
        USB_Init();
 }
 

-/** Processes the next audio sample by reading the last ADC conversion and writing it to the audio
- *  interface, each time the sample reload timer period elapses to give a constant sample rate.
- */
-void ProcessNextSample(void)
+/** ISR to handle the reloading of the PWM timer with the next sample. */
+ISR(TIMER0_COMPA_vect, ISR_BLOCK)

 {
 {

-       /* Check if the sample reload timer period has elapsed, and that the USB bus is ready for a new sample */
-       if ((TIFR0 & (1 << OCF0A)) && Audio_Device_IsSampleReceived(&Speaker_Audio_Interface))
-       {
-               /* Clear the sample reload timer compare flag, ready for the next interval */
-               TIFR0 |= (1 << OCF0A);
+       uint8_t PrevEndpoint = Endpoint_GetCurrentEndpoint();

 
 

+       if (Audio_Device_IsSampleReceived(&Speaker_Audio_Interface))
+       {

                /* Retrieve the signed 16-bit left and right audio samples, convert to 8-bit */
                /* Retrieve the signed 16-bit left and right audio samples, convert to 8-bit */

-               int8_t  LeftSample_8Bit   = (Audio_Device_ReadSample16(&Speaker_Audio_Interface) >> 8);
-               int8_t  RightSample_8Bit  = (Audio_Device_ReadSample16(&Speaker_Audio_Interface) >> 8);
+               int8_t LeftSample_8Bit  = (Audio_Device_ReadSample16(&Speaker_Audio_Interface) >> 8);
+               int8_t RightSample_8Bit = (Audio_Device_ReadSample16(&Speaker_Audio_Interface) >> 8);

 
                /* Mix the two channels together to produce a mono, 8-bit sample */
 
                /* Mix the two channels together to produce a mono, 8-bit sample */

-               int8_t  MixedSample_8Bit  = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);
+               int8_t MixedSample_8Bit = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);

 
 

-#if defined(AUDIO_OUT_MONO)
+               #if defined(AUDIO_OUT_MONO)

                /* Load the sample into the PWM timer channel */
                OCR3A = (MixedSample_8Bit ^ (1 << 7));
                /* Load the sample into the PWM timer channel */
                OCR3A = (MixedSample_8Bit ^ (1 << 7));

-#elif defined(AUDIO_OUT_STEREO)
+               #elif defined(AUDIO_OUT_STEREO)

                /* Load the dual 8-bit samples into the PWM timer channels */
                OCR3A = (LeftSample_8Bit  ^ (1 << 7));
                OCR3B = (RightSample_8Bit ^ (1 << 7));
                /* Load the dual 8-bit samples into the PWM timer channels */
                OCR3A = (LeftSample_8Bit  ^ (1 << 7));
                OCR3B = (RightSample_8Bit ^ (1 << 7));

-#elif defined(AUDIO_OUT_PORTC)
+               #elif defined(AUDIO_OUT_PORTC)

                /* Load the 8-bit mixed sample into PORTC */
                PORTC = MixedSample_8Bit;
                /* Load the 8-bit mixed sample into PORTC */
                PORTC = MixedSample_8Bit;

-#endif
+               #endif

 
                uint8_t LEDMask = LEDS_NO_LEDS;
 
 
                uint8_t LEDMask = LEDS_NO_LEDS;
 


@@ -129,6 +123,8 @@ void ProcessNextSample(void)
 
                LEDs_SetAllLEDs(LEDMask);
        }
 
                LEDs_SetAllLEDs(LEDMask);
        }

+       
+       Endpoint_SelectEndpoint(PrevEndpoint);  

 }
 
 /** Event handler for the library USB Connection event. */
 }
 
 /** Event handler for the library USB Connection event. */


@@ -137,27 +133,28 @@ void EVENT_USB_Device_Connect(void)
        LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 
        /* Sample reload timer initialization */
        LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 
        /* Sample reload timer initialization */

-       OCR0A   = (F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1;
+       TIMSK0  = (1 << OCIE0A);
+       OCR0A   = ((F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1);

        TCCR0A  = (1 << WGM01);  // CTC mode
        TCCR0B  = (1 << CS01);   // Fcpu/8 speed
 
        TCCR0A  = (1 << WGM01);  // CTC mode
        TCCR0B  = (1 << CS01);   // Fcpu/8 speed
 

-#if defined(AUDIO_OUT_MONO)
+       #if defined(AUDIO_OUT_MONO)

        /* Set speaker as output */
        DDRC   |= (1 << 6);
        /* Set speaker as output */
        DDRC   |= (1 << 6);

-#elif defined(AUDIO_OUT_STEREO)
+       #elif defined(AUDIO_OUT_STEREO)

        /* Set speakers as outputs */
        DDRC   |= ((1 << 6) | (1 << 5));
        /* Set speakers as outputs */
        DDRC   |= ((1 << 6) | (1 << 5));

-#elif defined(AUDIO_OUT_PORTC)
+       #elif defined(AUDIO_OUT_PORTC)

        /* Set PORTC as outputs */
        DDRC   |= 0xFF;
        /* Set PORTC as outputs */
        DDRC   |= 0xFF;

-#endif
+       #endif

 
 

-#if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))
+       #if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))

        /* PWM speaker timer initialization */
        TCCR3A  = ((1 << WGM30) | (1 << COM3A1) | (1 << COM3A0)
                | (1 << COM3B1) | (1 << COM3B0)); // Set on match, clear on TOP
        TCCR3B  = ((1 << WGM32) | (1 << CS30));  // Fast 8-Bit PWM, F_CPU speed
        /* PWM speaker timer initialization */
        TCCR3A  = ((1 << WGM30) | (1 << COM3A1) | (1 << COM3A0)
                | (1 << COM3B1) | (1 << COM3B0)); // Set on match, clear on TOP
        TCCR3B  = ((1 << WGM32) | (1 << CS30));  // Fast 8-Bit PWM, F_CPU speed

-#endif
+       #endif

 }
 
 /** Event handler for the library USB Disconnection event. */
 }
 
 /** Event handler for the library USB Disconnection event. */


@@ -168,21 +165,21 @@ void EVENT_USB_Device_Disconnect(void)
        /* Stop the sample reload timer */
        TCCR0B = 0;
 
        /* Stop the sample reload timer */
        TCCR0B = 0;
 

-#if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))
+       #if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))

        /* Stop the PWM generation timer */
        TCCR3B = 0;
        /* Stop the PWM generation timer */
        TCCR3B = 0;

-#endif
+       #endif

 
 

-#if defined(AUDIO_OUT_MONO)
+       #if defined(AUDIO_OUT_MONO)

        /* Set speaker as input to reduce current draw */
        /* Set speaker as input to reduce current draw */

-       DDRC   &= ~(1 << 6);
-#elif defined(AUDIO_OUT_STEREO)
+       DDRC  &= ~(1 << 6);
+       #elif defined(AUDIO_OUT_STEREO)

        /* Set speakers as inputs to reduce current draw */
        /* Set speakers as inputs to reduce current draw */

-       DDRC   &= ~((1 << 6) | (1 << 5));
-#elif defined(AUDIO_OUT_PORTC)
+       DDRC  &= ~((1 << 6) | (1 << 5));
+       #elif defined(AUDIO_OUT_PORTC)

        /* Set PORTC low */
        /* Set PORTC low */

-       PORTC  = 0x00;
-#endif
+       PORTC = 0x00;
+       #endif

 }
 
 /** Event handler for the library USB Configuration Changed event. */
 }
 
 /** Event handler for the library USB Configuration Changed event. */


@@ -195,8 +192,8 @@ void EVENT_USB_Device_ConfigurationChanged(void)
        LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
 }
 
        LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
 }
 

-/** Event handler for the library USB Unhandled Control Request event. */
-void EVENT_USB_Device_UnhandledControlRequest(void)
+/** Event handler for the library USB Control Request reception event. */
+void EVENT_USB_Device_ControlRequest(void)

 {
        Audio_Device_ProcessControlRequest(&Speaker_Audio_Interface);
 }
 {
        Audio_Device_ProcessControlRequest(&Speaker_Audio_Interface);
 }