/*
LUFA Library
Copyright (C) Dean Camera, 2010.
-
+
dean [at] fourwalledcubicle [dot] com
- www.fourwalledcubicle.com
+ www.lufa-lib.org
*/
/*
Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com)
- Permission to use, copy, modify, distribute, and sell this
+ Permission to use, copy, modify, distribute, and sell this
software and its documentation for any purpose is hereby granted
- without fee, provided that the above copyright notice appear in
+ without fee, provided that the above copyright notice appear in
all copies and that both that the copyright notice and this
- permission notice and warranty disclaimer appear in supporting
- documentation, and that the name of the author not be used in
- advertising or publicity pertaining to distribution of the
+ permission notice and warranty disclaimer appear in supporting
+ documentation, and that the name of the author not be used in
+ advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
The author disclaim all warranties with regard to this
LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
sei();
-
+
for (;;)
{
- ProcessNextSample();
-
Audio_Device_USBTask(&Speaker_Audio_Interface);
USB_USBTask();
}
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 */
- 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 */
- 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 */
- 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));
-#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));
-#elif defined(AUDIO_OUT_PORTC)
+ #elif defined(AUDIO_OUT_PORTC)
/* Load the 8-bit mixed sample into PORTC */
PORTC = MixedSample_8Bit;
-#endif
+ #endif
uint8_t LEDMask = LEDS_NO_LEDS;
LEDs_SetAllLEDs(LEDMask);
}
+
+ Endpoint_SelectEndpoint(PrevEndpoint);
}
/** Event handler for the library USB Connection event. */
void EVENT_USB_Device_Connect(void)
{
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
-#if defined(AUDIO_OUT_MONO)
+ #if defined(AUDIO_OUT_MONO)
/* 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));
-#elif defined(AUDIO_OUT_PORTC)
+ #elif defined(AUDIO_OUT_PORTC)
/* 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, Fcpu speed
-#endif
+ TCCR3B = ((1 << WGM32) | (1 << CS30)); // Fast 8-Bit PWM, F_CPU speed
+ #endif
}
/** Event handler for the library USB Disconnection event. */
/* 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;
-#endif
+ #endif
-#if defined(AUDIO_OUT_MONO)
+ #if defined(AUDIO_OUT_MONO)
/* 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 */
- DDRC &= ~((1 << 6) | (1 << 5));
-#elif defined(AUDIO_OUT_PORTC)
+ DDRC &= ~((1 << 6) | (1 << 5));
+ #elif defined(AUDIO_OUT_PORTC)
/* Set PORTC low */
- PORTC = 0x00;
-#endif
+ PORTC = 0x00;
+ #endif
}
/** Event handler for the library USB Configuration Changed event. */
void EVENT_USB_Device_ConfigurationChanged(void)
{
- LEDs_SetAllLEDs(LEDMASK_USB_READY);
-
- if (!(Audio_Device_ConfigureEndpoints(&Speaker_Audio_Interface)))
- LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
+ bool ConfigSuccess = true;
+
+ ConfigSuccess &= Audio_Device_ConfigureEndpoints(&Speaker_Audio_Interface);
+
+ 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);
}
+
projects / pub / USBasp.git / blobdiff