diff options
Diffstat (limited to 'Demos/Device/LowLevel/AudioInput/AudioInput.c')
-rw-r--r-- | Demos/Device/LowLevel/AudioInput/AudioInput.c | 376 |
1 files changed, 188 insertions, 188 deletions
diff --git a/Demos/Device/LowLevel/AudioInput/AudioInput.c b/Demos/Device/LowLevel/AudioInput/AudioInput.c index aa8967cd0..6655a27ee 100644 --- a/Demos/Device/LowLevel/AudioInput/AudioInput.c +++ b/Demos/Device/LowLevel/AudioInput/AudioInput.c @@ -1,188 +1,188 @@ -/*
- LUFA Library
- Copyright (C) Dean Camera, 2010.
-
- dean [at] fourwalledcubicle [dot] com
- www.fourwalledcubicle.com
-*/
-
-/*
- Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com)
-
- 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
- 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
- software without specific, written prior permission.
-
- The author disclaim all warranties with regard to this
- software, including all implied warranties of merchantability
- and fitness. In no event shall the author be liable for any
- special, indirect or consequential damages or any damages
- whatsoever resulting from loss of use, data or profits, whether
- in an action of contract, negligence or other tortious action,
- arising out of or in connection with the use or performance of
- this software.
-*/
-
-/** \file
- *
- * Main source file for the Audio Input demo. This file contains the main tasks of the demo and
- * is responsible for the initial application hardware configuration.
- */
-
-#include "AudioInput.h"
-
-/** Flag to indicate if the streaming audio alternative interface has been selected by the host. */
-bool StreamingAudioInterfaceSelected = false;
-
-/** Main program entry point. This routine contains the overall program flow, including initial
- * setup of all components and the main program loop.
- */
-int main(void)
-{
- SetupHardware();
-
- LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
- sei();
-
- for (;;)
- {
- USB_Audio_Task();
- USB_USBTask();
- }
-}
-
-/** Configures the board hardware and chip peripherals for the demo's functionality. */
-void SetupHardware(void)
-{
- /* Disable watchdog if enabled by bootloader/fuses */
- MCUSR &= ~(1 << WDRF);
- wdt_disable();
-
- /* Disable clock division */
- clock_prescale_set(clock_div_1);
-
- /* Hardware Initialization */
- LEDs_Init();
- ADC_Init(ADC_FREE_RUNNING | ADC_PRESCALE_32);
- ADC_SetupChannel(MIC_IN_ADC_CHANNEL);
- USB_Init();
-
- /* Start the ADC conversion in free running mode */
- ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | MIC_IN_ADC_MUX_MASK);
-}
-
-/** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs, and
- * configures the sample update and PWM timers.
- */
-void EVENT_USB_Device_Connect(void)
-{
- /* Indicate USB enumerating */
- LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
-
- /* Sample reload timer initialization */
- OCR0A = (F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1;
- TCCR0A = (1 << WGM01); // CTC mode
- TCCR0B = (1 << CS01); // Fcpu/8 speed
-}
-
-/** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
- * the status LEDs, disables the sample update and PWM output timers and stops the USB and Audio management tasks.
- */
-void EVENT_USB_Device_Disconnect(void)
-{
- /* Stop the sample reload timer */
- TCCR0B = 0;
-
- /* Indicate streaming audio interface not selected */
- StreamingAudioInterfaceSelected = false;
-
- /* Indicate USB not ready */
- LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
-}
-
-/** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
- * of the USB device after enumeration - the device endpoints are configured.
- */
-void EVENT_USB_Device_ConfigurationChanged(void)
-{
- /* Indicate USB connected and ready */
- LEDs_SetAllLEDs(LEDMASK_USB_READY);
-
- /* Setup audio stream endpoint */
- if (!(Endpoint_ConfigureEndpoint(AUDIO_STREAM_EPNUM, EP_TYPE_ISOCHRONOUS,
- ENDPOINT_DIR_IN, AUDIO_STREAM_EPSIZE,
- ENDPOINT_BANK_DOUBLE)))
- {
- LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
- }
-}
-
-/** Event handler for the USB_UnhandledControlRequest event. This is used to catch standard and class specific
- * control requests that are not handled internally by the USB library (including the Audio class-specific
- * requests) so that they can be handled appropriately for the application.
- */
-void EVENT_USB_Device_UnhandledControlRequest(void)
-{
- /* Process General and Audio specific control requests */
- switch (USB_ControlRequest.bRequest)
- {
- case REQ_SetInterface:
- /* Set Interface is not handled by the library, as its function is application-specific */
- if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_STANDARD | REQREC_INTERFACE))
- {
- Endpoint_ClearSETUP();
-
- /* Check if the host is enabling the audio interface (setting AlternateSetting to 1) */
- StreamingAudioInterfaceSelected = ((USB_ControlRequest.wValue) != 0);
-
- Endpoint_ClearStatusStage();
- }
-
- break;
- }
-}
-
-/** Task to manage the Audio interface, reading in ADC samples from the microphone, and them to the host. */
-void USB_Audio_Task(void)
-{
- /* 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;
-
- /* 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)))
- {
- /* Clear the sample reload timer */
- TIFR0 |= (1 << OCF0A);
-
- /* Audio sample is ADC value scaled to fit the entire range */
- int16_t AudioSample = ((SAMPLE_MAX_RANGE / ADC_MAX_RANGE) * ADC_GetResult());
-
- #if defined(MICROPHONE_BIASED_TO_HALF_RAIL)
- /* Microphone is biased to half rail voltage, subtract the bias from the sample value */
- AudioSample -= (SAMPLE_MAX_RANGE / 2);
- #endif
-
- /* Write the sample to the buffer */
- Endpoint_Write_Word_LE(AudioSample);
-
- /* Check to see if the bank is now full */
- if (!(Endpoint_IsReadWriteAllowed()))
- {
- /* Send the full packet to the host */
- Endpoint_ClearIN();
- }
- }
-}
+/* + LUFA Library + Copyright (C) Dean Camera, 2010. + + dean [at] fourwalledcubicle [dot] com + www.fourwalledcubicle.com +*/ + +/* + Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com) + + 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 + 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 + software without specific, written prior permission. + + The author disclaim all warranties with regard to this + software, including all implied warranties of merchantability + and fitness. In no event shall the author be liable for any + special, indirect or consequential damages or any damages + whatsoever resulting from loss of use, data or profits, whether + in an action of contract, negligence or other tortious action, + arising out of or in connection with the use or performance of + this software. +*/ + +/** \file + * + * Main source file for the Audio Input demo. This file contains the main tasks of the demo and + * is responsible for the initial application hardware configuration. + */ + +#include "AudioInput.h" + +/** Flag to indicate if the streaming audio alternative interface has been selected by the host. */ +bool StreamingAudioInterfaceSelected = false; + +/** Main program entry point. This routine contains the overall program flow, including initial + * setup of all components and the main program loop. + */ +int main(void) +{ + SetupHardware(); + + LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY); + sei(); + + for (;;) + { + USB_Audio_Task(); + USB_USBTask(); + } +} + +/** Configures the board hardware and chip peripherals for the demo's functionality. */ +void SetupHardware(void) +{ + /* Disable watchdog if enabled by bootloader/fuses */ + MCUSR &= ~(1 << WDRF); + wdt_disable(); + + /* Disable clock division */ + clock_prescale_set(clock_div_1); + + /* Hardware Initialization */ + LEDs_Init(); + ADC_Init(ADC_FREE_RUNNING | ADC_PRESCALE_32); + ADC_SetupChannel(MIC_IN_ADC_CHANNEL); + USB_Init(); + + /* Start the ADC conversion in free running mode */ + ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | MIC_IN_ADC_MUX_MASK); +} + +/** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs, and + * configures the sample update and PWM timers. + */ +void EVENT_USB_Device_Connect(void) +{ + /* Indicate USB enumerating */ + LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING); + + /* Sample reload timer initialization */ + OCR0A = (F_CPU / 8 / AUDIO_SAMPLE_FREQUENCY) - 1; + TCCR0A = (1 << WGM01); // CTC mode + TCCR0B = (1 << CS01); // Fcpu/8 speed +} + +/** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via + * the status LEDs, disables the sample update and PWM output timers and stops the USB and Audio management tasks. + */ +void EVENT_USB_Device_Disconnect(void) +{ + /* Stop the sample reload timer */ + TCCR0B = 0; + + /* Indicate streaming audio interface not selected */ + StreamingAudioInterfaceSelected = false; + + /* Indicate USB not ready */ + LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY); +} + +/** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration + * of the USB device after enumeration - the device endpoints are configured. + */ +void EVENT_USB_Device_ConfigurationChanged(void) +{ + /* Indicate USB connected and ready */ + LEDs_SetAllLEDs(LEDMASK_USB_READY); + + /* Setup audio stream endpoint */ + if (!(Endpoint_ConfigureEndpoint(AUDIO_STREAM_EPNUM, EP_TYPE_ISOCHRONOUS, + ENDPOINT_DIR_IN, AUDIO_STREAM_EPSIZE, + ENDPOINT_BANK_DOUBLE))) + { + LEDs_SetAllLEDs(LEDMASK_USB_ERROR); + } +} + +/** Event handler for the USB_UnhandledControlRequest event. This is used to catch standard and class specific + * control requests that are not handled internally by the USB library (including the Audio class-specific + * requests) so that they can be handled appropriately for the application. + */ +void EVENT_USB_Device_UnhandledControlRequest(void) +{ + /* Process General and Audio specific control requests */ + switch (USB_ControlRequest.bRequest) + { + case REQ_SetInterface: + /* Set Interface is not handled by the library, as its function is application-specific */ + if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_STANDARD | REQREC_INTERFACE)) + { + Endpoint_ClearSETUP(); + + /* Check if the host is enabling the audio interface (setting AlternateSetting to 1) */ + StreamingAudioInterfaceSelected = ((USB_ControlRequest.wValue) != 0); + + Endpoint_ClearStatusStage(); + } + + break; + } +} + +/** Task to manage the Audio interface, reading in ADC samples from the microphone, and them to the host. */ +void USB_Audio_Task(void) +{ + /* 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; + + /* 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))) + { + /* Clear the sample reload timer */ + TIFR0 |= (1 << OCF0A); + + /* Audio sample is ADC value scaled to fit the entire range */ + int16_t AudioSample = ((SAMPLE_MAX_RANGE / ADC_MAX_RANGE) * ADC_GetResult()); + + #if defined(MICROPHONE_BIASED_TO_HALF_RAIL) + /* Microphone is biased to half rail voltage, subtract the bias from the sample value */ + AudioSample -= (SAMPLE_MAX_RANGE / 2); + #endif + + /* Write the sample to the buffer */ + Endpoint_Write_Word_LE(AudioSample); + + /* Check to see if the bank is now full */ + if (!(Endpoint_IsReadWriteAllowed())) + { + /* Send the full packet to the host */ + Endpoint_ClearIN(); + } + } +} |