\r
/** \file\r
*\r
- * Main source file for the Audio Output demo. This file contains the main tasks of the demo and\r
- * is responsible for the initial application hardware configuration.\r
+ * Main source file for the AudioOutput demo. This file contains the main tasks of\r
+ * the demo and is responsible for the initial application hardware configuration.\r
*/\r
- \r
+\r
#include "AudioOutput.h"\r
\r
-/* Scheduler Task List */\r
-TASK_LIST\r
-{\r
- { .Task = USB_USBTask , .TaskStatus = TASK_STOP },\r
- { .Task = USB_Audio_Task , .TaskStatus = TASK_STOP },\r
-};\r
+/** LUFA Audio Class driver interface configuration and state information. This structure is\r
+ * passed to all Audio Class driver functions, so that multiple instances of the same class\r
+ * within a device can be differentiated from one another.\r
+ */\r
+USB_ClassInfo_Audio_t Speaker_Audio_Interface =\r
+ {\r
+ .StreamingInterfaceNumber = 1,\r
\r
+ .DataOUTEndpointNumber = AUDIO_STREAM_EPNUM,\r
+ .DataOUTEndpointSize = AUDIO_STREAM_EPSIZE,\r
+ };\r
\r
-/** Main program entry point. This routine configures the hardware required by the application, then\r
- * starts the scheduler to run the application tasks.\r
+/** Main program entry point. This routine contains the overall program flow, including initial\r
+ * setup of all components and the main program loop.\r
*/\r
int main(void)\r
{\r
+ SetupHardware();\r
+\r
+ LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);\r
+ \r
+ for (;;)\r
+ {\r
+ if (Speaker_Audio_Interface.InterfaceEnabled)\r
+ ProcessNextSample();\r
+\r
+ USB_Audio_USBTask(&Speaker_Audio_Interface);\r
+ USB_USBTask();\r
+ }\r
+}\r
+\r
+/** Configures the board hardware and chip peripherals for the demo's functionality. */\r
+void SetupHardware(void)\r
+{\r
/* Disable watchdog if enabled by bootloader/fuses */\r
MCUSR &= ~(1 << WDRF);\r
wdt_disable();\r
\r
/* Hardware Initialization */\r
LEDs_Init();\r
- \r
- /* Indicate USB not ready */\r
- UpdateStatus(Status_USBNotReady);\r
- \r
- /* Initialize Scheduler so that it can be used */\r
- Scheduler_Init();\r
-\r
- /* Initialize USB Subsystem */\r
USB_Init();\r
-\r
- /* Scheduling - routine never returns, so put this last in the main function */\r
- Scheduler_Start();\r
}\r
\r
-/** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs, and\r
- * configures the sample update and PWM timers.\r
+/** Processes the next audio sample by reading the last ADC conversion and writing it to the audio\r
+ * interface, each time the sample reload timer period elapses to give a constant sample rate.\r
*/\r
-EVENT_HANDLER(USB_Connect)\r
+void ProcessNextSample(void)\r
{\r
- /* Start USB management task */\r
- Scheduler_SetTaskMode(USB_USBTask, TASK_RUN);\r
+ if ((TIFR0 & (1 << OCF0A)) && USB_Audio_IsSampleReceived(&Speaker_Audio_Interface))\r
+ {\r
+ /* Clear the sample reload timer */\r
+ TIFR0 |= (1 << OCF0A);\r
+\r
+ /* Retrieve the signed 16-bit left and right audio samples */\r
+ int16_t LeftSample_16Bit = (int16_t)USB_Audio_ReadSample16();\r
+ int16_t RightSample_16Bit = (int16_t)USB_Audio_ReadSample16();\r
\r
- /* Indicate USB enumerating */\r
- UpdateStatus(Status_USBEnumerating);\r
+ /* Massage signed 16-bit left and right audio samples into signed 8-bit */\r
+ int8_t LeftSample_8Bit = (LeftSample_16Bit >> 8);\r
+ int8_t RightSample_8Bit = (RightSample_16Bit >> 8);\r
+ \r
+ /* Mix the two channels together to produce a mono, 8-bit sample */\r
+ int8_t MixedSample_8Bit = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);\r
+\r
+#if defined(AUDIO_OUT_MONO)\r
+ /* Load the sample into the PWM timer channel */\r
+ OCRxA = ((uint8_t)MixedSample_8Bit ^ (1 << 7));\r
+#elif defined(AUDIO_OUT_STEREO)\r
+ /* Load the dual 8-bit samples into the PWM timer channels */\r
+ OCRxA = ((uint8_t)LeftSample_8Bit ^ (1 << 7));\r
+ OCRxB = ((uint8_t)RightSample_8Bit ^ (1 << 7));\r
+#elif defined(AUDIO_OUT_PORTC)\r
+ PORTC = MixedSample_8Bit;\r
+#else\r
+ uint8_t LEDMask = LEDS_NO_LEDS;\r
+\r
+ /* Make mixed sample value positive (absolute) */\r
+ if (MixedSample_8Bit < 0)\r
+ MixedSample_8Bit = -MixedSample_8Bit;\r
+\r
+ if (MixedSample_8Bit > ((128 / 8) * 1))\r
+ LEDMask |= LEDS_LED1;\r
+ \r
+ if (MixedSample_8Bit > ((128 / 8) * 2))\r
+ LEDMask |= LEDS_LED2;\r
+ \r
+ if (MixedSample_8Bit > ((128 / 8) * 3))\r
+ LEDMask |= LEDS_LED3;\r
+\r
+ if (MixedSample_8Bit > ((128 / 8) * 4))\r
+ LEDMask |= LEDS_LED4;\r
+\r
+ LEDs_SetAllLEDs(LEDMask);\r
+#endif\r
+ }\r
+}\r
+\r
+/** Event handler for the library USB Connection event. */\r
+void EVENT_USB_Connect(void)\r
+{\r
+ LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);\r
\r
/* Sample reload timer initialization */\r
OCR0A = (F_CPU / AUDIO_SAMPLE_FREQUENCY) - 1;\r
TCCR0A = (1 << WGM01); // CTC mode\r
TCCR0B = (1 << CS00); // Fcpu speed\r
- \r
+\r
#if defined(AUDIO_OUT_MONO)\r
/* Set speaker as output */\r
DDRC |= (1 << 6);\r
#endif \r
}\r
\r
-/** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via\r
- * the status LEDs, disables the sample update and PWM output timers and stops the USB and Audio management tasks.\r
- */\r
-EVENT_HANDLER(USB_Disconnect)\r
+/** Event handler for the library USB Disconnection event. */\r
+void EVENT_USB_Disconnect(void)\r
{\r
- /* Stop the timers */\r
+ LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);\r
+\r
+ /* Stop the sample reload timer */\r
TCCR0B = 0;\r
+\r
#if (defined(AUDIO_OUT_MONO) || defined(AUDIO_OUT_STEREO))\r
+ /* Stop the PWM generation timer */\r
TCCRxB = 0;\r
#endif \r
\r
/* Set PORTC low */\r
PORTC = 0x00;\r
#endif\r
-\r
- /* Stop running audio and USB management tasks */\r
- Scheduler_SetTaskMode(USB_Audio_Task, TASK_STOP);\r
- Scheduler_SetTaskMode(USB_USBTask, TASK_STOP);\r
-\r
- /* Indicate USB not ready */\r
- UpdateStatus(Status_USBNotReady);\r
-}\r
-\r
-/** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration\r
- * of the USB device after enumeration - the device endpoints are configured.\r
- */\r
-EVENT_HANDLER(USB_ConfigurationChanged)\r
-{\r
- /* Setup audio stream endpoint */\r
- Endpoint_ConfigureEndpoint(AUDIO_STREAM_EPNUM, EP_TYPE_ISOCHRONOUS,\r
- ENDPOINT_DIR_OUT, AUDIO_STREAM_EPSIZE,\r
- ENDPOINT_BANK_DOUBLE);\r
-\r
- /* Indicate USB connected and ready */\r
- UpdateStatus(Status_USBReady);\r
}\r
\r
-/** Event handler for the USB_UnhandledControlPacket event. This is used to catch standard and class specific\r
- * control requests that are not handled internally by the USB library (including the Audio class-specific\r
- * requests) so that they can be handled appropriately for the application.\r
- */\r
-EVENT_HANDLER(USB_UnhandledControlPacket)\r
-{\r
- /* Process General and Audio specific control requests */\r
- switch (USB_ControlRequest.bRequest)\r
- {\r
- case REQ_SetInterface:\r
- /* Set Interface is not handled by the library, as its function is application-specific */\r
- if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_STANDARD | REQREC_INTERFACE))\r
- {\r
- Endpoint_ClearSETUP();\r
- \r
- /* Check if the host is enabling the audio interface (setting AlternateSetting to 1) */\r
- if (USB_ControlRequest.wValue)\r
- {\r
- /* Start audio task */\r
- Scheduler_SetTaskMode(USB_Audio_Task, TASK_RUN);\r
- }\r
- else\r
- {\r
- /* Stop audio task */\r
- Scheduler_SetTaskMode(USB_Audio_Task, TASK_STOP); \r
- }\r
- \r
- /* Acknowledge status stage */\r
- while (!(Endpoint_IsINReady()));\r
- Endpoint_ClearIN();\r
- }\r
-\r
- break;\r
- }\r
-}\r
-\r
-/** Function to manage status updates to the user. This is done via LEDs on the given board, if available, but may be changed to\r
- * log to a serial port, or anything else that is suitable for status updates.\r
- *\r
- * \param CurrentStatus Current status of the system, from the AudioOutput_StatusCodes_t enum\r
- */\r
-void UpdateStatus(uint8_t CurrentStatus)\r
+/** Event handler for the library USB Configuration Changed event. */\r
+void EVENT_USB_ConfigurationChanged(void)\r
{\r
- uint8_t LEDMask = LEDS_NO_LEDS;\r
+ LEDs_SetAllLEDs(LEDMASK_USB_READY);\r
\r
- /* Set the LED mask to the appropriate LED mask based on the given status code */\r
- switch (CurrentStatus)\r
- {\r
- case Status_USBNotReady:\r
- LEDMask = (LEDS_LED1);\r
- break;\r
- case Status_USBEnumerating:\r
- LEDMask = (LEDS_LED1 | LEDS_LED2);\r
- break;\r
- case Status_USBReady:\r
- LEDMask = (LEDS_LED2 | LEDS_LED4);\r
- break;\r
- }\r
- \r
- /* Set the board LEDs to the new LED mask */\r
- LEDs_SetAllLEDs(LEDMask);\r
+ if (!(USB_Audio_ConfigureEndpoints(&Speaker_Audio_Interface)))\r
+ LEDs_SetAllLEDs(LEDMASK_USB_ERROR);\r
}\r
\r
-/** Task to manage the Audio interface, reading in audio samples from the host, and outputting them to the speakers/LEDs as\r
- * desired.\r
- */\r
-TASK(USB_Audio_Task)\r
+/** Event handler for the library USB Unhandled Control Packet event. */\r
+void EVENT_USB_UnhandledControlPacket(void)\r
{\r
- /* Select the audio stream endpoint */\r
- Endpoint_SelectEndpoint(AUDIO_STREAM_EPNUM);\r
- \r
- /* Check if the current endpoint can be read from (contains a packet) and that the next sample should be read */\r
- if (Endpoint_IsOUTReceived() && (TIFR0 & (1 << OCF0A)))\r
- {\r
- /* Clear the sample reload timer */\r
- TIFR0 |= (1 << OCF0A);\r
-\r
- /* Retrieve the signed 16-bit left and right audio samples */\r
- int16_t LeftSample_16Bit = (int16_t)Endpoint_Read_Word_LE();\r
- int16_t RightSample_16Bit = (int16_t)Endpoint_Read_Word_LE();\r
-\r
- /* Check to see if the bank is now empty */\r
- if (!(Endpoint_IsReadWriteAllowed()))\r
- {\r
- /* Acknowledge the packet, clear the bank ready for the next packet */\r
- Endpoint_ClearOUT();\r
- }\r
-\r
- /* Massage signed 16-bit left and right audio samples into signed 8-bit */\r
- int8_t LeftSample_8Bit = (LeftSample_16Bit >> 8);\r
- int8_t RightSample_8Bit = (RightSample_16Bit >> 8);\r
- \r
-#if defined(AUDIO_OUT_MONO)\r
- /* Mix the two channels together to produce a mono, 8-bit sample */\r
- int8_t MixedSample_8Bit = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);\r
-\r
- /* Load the sample into the PWM timer channel */\r
- OCRxA = ((uint8_t)MixedSample_8Bit ^ (1 << 7));\r
-#elif defined(AUDIO_OUT_STEREO)\r
- /* Load the dual 8-bit samples into the PWM timer channels */\r
- OCRxA = ((uint8_t)LeftSample_8Bit ^ (1 << 7));\r
- OCRxB = ((uint8_t)RightSample_8Bit ^ (1 << 7));\r
-#elif defined(AUDIO_OUT_PORTC)\r
- /* Mix the two channels together to produce a mono, 8-bit sample */\r
- int8_t MixedSample_8Bit = (((int16_t)LeftSample_8Bit + (int16_t)RightSample_8Bit) >> 1);\r
-\r
- PORTC = MixedSample_8Bit;\r
-#else\r
- uint8_t LEDMask = LEDS_NO_LEDS;\r
-\r
- /* Make left channel positive (absolute) */\r
- if (LeftSample_8Bit < 0)\r
- LeftSample_8Bit = -LeftSample_8Bit;\r
-\r
- /* Make right channel positive (absolute) */\r
- if (RightSample_8Bit < 0)\r
- RightSample_8Bit = -RightSample_8Bit;\r
-\r
- /* Set first LED based on sample value */\r
- if (LeftSample_8Bit < ((128 / 8) * 1))\r
- LEDMask |= LEDS_LED2;\r
- else if (LeftSample_8Bit < ((128 / 8) * 3))\r
- LEDMask |= (LEDS_LED1 | LEDS_LED2);\r
- else\r
- LEDMask |= LEDS_LED1;\r
-\r
- /* Set second LED based on sample value */\r
- if (RightSample_8Bit < ((128 / 8) * 1))\r
- LEDMask |= LEDS_LED4;\r
- else if (RightSample_8Bit < ((128 / 8) * 3))\r
- LEDMask |= (LEDS_LED3 | LEDS_LED4);\r
- else\r
- LEDMask |= LEDS_LED3;\r
- \r
- LEDs_SetAllLEDs(LEDMask);\r
-#endif\r
- }\r
+ USB_Audio_ProcessControlPacket(&Speaker_Audio_Interface);\r
}\r