Demos/Host/LowLevel/AudioOutputHost/AudioOutputHost.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2013.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2013  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaims all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  Main source file for the AudioOutputHost demo. This file contains the main tasks of
  34  *  the demo and is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "AudioOutputHost.h"
  38
  39 /** Main program entry point. This routine configures the hardware required by the application, then
  40  *  enters a loop to run the application tasks in sequence.
  41  */
  42 int main(void)
  43 {
  44         SetupHardware();
  45
  46         puts_P(PSTR(ESC_FG_CYAN "Audio Output Host Demo running.\r\n" ESC_FG_WHITE));
  47
  48         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  49         GlobalInterruptEnable();
  50
  51         for (;;)
  52         {
  53                 USB_USBTask();
  54         }
  55 }
  56
  57 /** Configures the board hardware and chip peripherals for the demo's functionality. */
  58 void SetupHardware(void)
  59 {
  60         /* Disable watchdog if enabled by bootloader/fuses */
  61         MCUSR &= ~(1 << WDRF);
  62         wdt_disable();
  63
  64         /* Disable clock division */
  65         clock_prescale_set(clock_div_1);
  66
  67         /* Hardware Initialization */
  68         Serial_Init(9600, false);
  69         Buttons_Init();
  70         ADC_Init(ADC_FREE_RUNNING | ADC_PRESCALE_32);
  71         ADC_SetupChannel(MIC_IN_ADC_CHANNEL);
  72         LEDs_Init();
  73         USB_Init();
  74
  75         /* Create a stdio stream for the serial port for stdin and stdout */
  76         Serial_CreateStream(NULL);
  77
  78         /* Start the ADC conversion in free running mode */
  79         ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | ADC_GET_CHANNEL_MASK(MIC_IN_ADC_CHANNEL));
  80 }
  81
  82 /** Event handler for the USB_DeviceAttached event. This indicates that a device has been attached to the host, and
  83  *  starts the library USB task to begin the enumeration and USB management process.
  84  */
  85 void EVENT_USB_Host_DeviceAttached(void)
  86 {
  87         puts_P(PSTR(ESC_FG_GREEN "Device Attached.\r\n" ESC_FG_WHITE));
  88         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
  89 }
  90
  91 /** Event handler for the USB_DeviceUnattached event. This indicates that a device has been removed from the host, and
  92  *  stops the library USB task management process.
  93  */
  94 void EVENT_USB_Host_DeviceUnattached(void)
  95 {
  96         puts_P(PSTR(ESC_FG_GREEN "Device Unattached.\r\n" ESC_FG_WHITE));
  97         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  98 }
  99
 100 /** Event handler for the USB_DeviceEnumerationComplete event. This indicates that a device has been successfully
 101  *  enumerated by the host and is now ready to be used by the application.
 102  */
 103 void EVENT_USB_Host_DeviceEnumerationComplete(void)
 104 {
 105         puts_P(PSTR("Getting Config Data.\r\n"));
 106
 107         uint8_t ErrorCode;
 108
 109         /* Get and process the configuration descriptor data */
 110         if ((ErrorCode = ProcessConfigurationDescriptor()) != SuccessfulConfigRead)
 111         {
 112                 if (ErrorCode == ControlError)
 113                   puts_P(PSTR(ESC_FG_RED "Control Error (Get Configuration).\r\n"));
 114                 else
 115                   puts_P(PSTR(ESC_FG_RED "Invalid Device.\r\n"));
 116
 117                 printf_P(PSTR(" -- Error Code: %d\r\n" ESC_FG_WHITE), ErrorCode);
 118
 119                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 120                 return;
 121         }
 122
 123         /* Set the device configuration to the first configuration (rarely do devices use multiple configurations) */
 124         if ((ErrorCode = USB_Host_SetDeviceConfiguration(1)) != HOST_SENDCONTROL_Successful)
 125         {
 126                 printf_P(PSTR(ESC_FG_RED "Control Error (Set Configuration).\r\n"
 127                                          " -- Error Code: %d\r\n" ESC_FG_WHITE), ErrorCode);
 128
 129                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 130                 return;
 131         }
 132
 133         if ((ErrorCode = USB_Host_SetInterfaceAltSetting(StreamingInterfaceIndex,
 134                                                          StreamingInterfaceAltSetting)) != HOST_SENDCONTROL_Successful)
 135         {
 136                 printf_P(PSTR(ESC_FG_RED "Could not set alternative streaming interface setting.\r\n"
 137                                          " -- Error Code: %d\r\n" ESC_FG_WHITE), ErrorCode);
 138
 139                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 140                 USB_Host_SetDeviceConfiguration(0);
 141                 return;
 142         }
 143
 144         USB_ControlRequest = (USB_Request_Header_t)
 145                 {
 146                         .bmRequestType = (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_ENDPOINT),
 147                         .bRequest      = AUDIO_REQ_SetCurrent,
 148                         .wValue        = (AUDIO_EPCONTROL_SamplingFreq << 8),
 149                         .wIndex        = StreamingEndpointAddress,
 150                         .wLength       = sizeof(USB_Audio_SampleFreq_t),
 151                 };
 152
 153         USB_Audio_SampleFreq_t SampleRate = AUDIO_SAMPLE_FREQ(48000);
 154
 155         /* Select the control pipe for the request transfer */
 156         Pipe_SelectPipe(PIPE_CONTROLPIPE);
 157
 158         /* Set the sample rate on the streaming interface endpoint */
 159         if ((ErrorCode = USB_Host_SendControlRequest(&SampleRate)) != HOST_SENDCONTROL_Successful)
 160         {
 161                 printf_P(PSTR(ESC_FG_RED "Could not set requested Audio sample rate.\r\n"
 162                                          " -- Error Code: %d\r\n" ESC_FG_WHITE), ErrorCode);
 163
 164                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 165                 USB_Host_SetDeviceConfiguration(0);
 166                 return;
 167         }
 168
 169         /* Sample reload timer initialization */
 170         TIMSK0  = (1 << OCIE0A);
 171         OCR0A   = ((F_CPU / 8 / 48000) - 1);
 172         TCCR0A  = (1 << WGM01);  // CTC mode
 173         TCCR0B  = (1 << CS01);   // Fcpu/8 speed
 174
 175         puts_P(PSTR("Speaker Enumerated.\r\n"));
 176         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 177 }
 178
 179 /** Event handler for the USB_HostError event. This indicates that a hardware error occurred while in host mode. */
 180 void EVENT_USB_Host_HostError(const uint8_t ErrorCode)
 181 {
 182         USB_Disable();
 183
 184         printf_P(PSTR(ESC_FG_RED "Host Mode Error\r\n"
 185                                  " -- Error Code %d\r\n" ESC_FG_WHITE), ErrorCode);
 186
 187         LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 188         for(;;);
 189 }
 190
 191 /** Event handler for the USB_DeviceEnumerationFailed event. This indicates that a problem occurred while
 192  *  enumerating an attached USB device.
 193  */
 194 void EVENT_USB_Host_DeviceEnumerationFailed(const uint8_t ErrorCode,
 195                                             const uint8_t SubErrorCode)
 196 {
 197         printf_P(PSTR(ESC_FG_RED "Dev Enum Error\r\n"
 198                                  " -- Error Code %d\r\n"
 199                                  " -- Sub Error Code %d\r\n"
 200                                  " -- In State %d\r\n" ESC_FG_WHITE), ErrorCode, SubErrorCode, USB_HostState);
 201
 202         LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 203 }
 204
 205 /** ISR to handle the reloading of the endpoint with the next sample. */
 206 ISR(TIMER0_COMPA_vect, ISR_BLOCK)
 207 {
 208         uint8_t PrevPipe = Pipe_GetCurrentPipe();
 209
 210         Pipe_SelectPipe(AUDIO_DATA_OUT_PIPE);
 211         Pipe_Unfreeze();
 212
 213         /* Check if the current pipe can be written to (device ready for more data) */
 214         if (Pipe_IsOUTReady())
 215         {
 216                 int16_t AudioSample;
 217
 218                 #if defined(USE_TEST_TONE)
 219                         static uint8_t SquareWaveSampleCount;
 220                         static int16_t CurrentWaveValue;
 221
 222                         /* In test tone mode, generate a square wave at 1/256 of the sample rate */
 223                         if (SquareWaveSampleCount++ == 0xFF)
 224                           CurrentWaveValue ^= 0x8000;
 225
 226                         /* Only generate audio if the board button is being pressed */
 227                         AudioSample = (Buttons_GetStatus() & BUTTONS_BUTTON1) ? CurrentWaveValue : 0;
 228                 #else
 229                         /* Audio sample is ADC value scaled to fit the entire range */
 230                         AudioSample = ((SAMPLE_MAX_RANGE / ADC_MAX_RANGE) * ADC_GetResult());
 231
 232                         #if defined(MICROPHONE_BIASED_TO_HALF_RAIL)
 233                         /* Microphone is biased to half rail voltage, subtract the bias from the sample value */
 234                         AudioSample -= (SAMPLE_MAX_RANGE / 2);
 235                         #endif
 236                 #endif
 237
 238                 Pipe_Write_16_LE(AudioSample);
 239                 Pipe_Write_16_LE(AudioSample);
 240
 241                 if (!(Pipe_IsReadWriteAllowed()))
 242                   Pipe_ClearOUT();
 243         }
 244
 245         Pipe_Freeze();
 246         Pipe_SelectPipe(PrevPipe);
 247 }
 248