Demos/Host/LowLevel/AudioOutputHost/AudioOutputHost.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2011.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2011  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 disclaim 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         sei();
  50
  51         for (;;)
  52         {
  53                 Audio_Task();
  54                 USB_USBTask();
  55         }
  56 }
  57
  58 /** Configures the board hardware and chip peripherals for the demo's functionality. */
  59 void SetupHardware(void)
  60 {
  61         /* Disable watchdog if enabled by bootloader/fuses */
  62         MCUSR &= ~(1 << WDRF);
  63         wdt_disable();
  64
  65         /* Disable clock division */
  66         clock_prescale_set(clock_div_1);
  67
  68         /* Hardware Initialization */
  69         Serial_Init(9600, false);
  70         Buttons_Init();
  71         LEDs_Init();
  72         USB_Init();
  73
  74         /* Create a stdio stream for the serial port for stdin and stdout */
  75         Serial_CreateStream(NULL);
  76 }
  77
  78 /** Event handler for the USB_DeviceAttached event. This indicates that a device has been attached to the host, and
  79  *  starts the library USB task to begin the enumeration and USB management process.
  80  */
  81 void EVENT_USB_Host_DeviceAttached(void)
  82 {
  83         puts_P(PSTR(ESC_FG_GREEN "Device Attached.\r\n" ESC_FG_WHITE));
  84         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
  85 }
  86
  87 /** Event handler for the USB_DeviceUnattached event. This indicates that a device has been removed from the host, and
  88  *  stops the library USB task management process.
  89  */
  90 void EVENT_USB_Host_DeviceUnattached(void)
  91 {
  92         puts_P(PSTR(ESC_FG_GREEN "Device Unattached.\r\n" ESC_FG_WHITE));
  93         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  94 }
  95
  96 /** Event handler for the USB_DeviceEnumerationComplete event. This indicates that a device has been successfully
  97  *  enumerated by the host and is now ready to be used by the application.
  98  */
  99 void EVENT_USB_Host_DeviceEnumerationComplete(void)
 100 {
 101         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 102 }
 103
 104 /** Event handler for the USB_HostError event. This indicates that a hardware error occurred while in host mode. */
 105 void EVENT_USB_Host_HostError(const uint8_t ErrorCode)
 106 {
 107         USB_Disable();
 108
 109         printf_P(PSTR(ESC_FG_RED "Host Mode Error\r\n"
 110                                  " -- Error Code %d\r\n" ESC_FG_WHITE), ErrorCode);
 111
 112         LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 113         for(;;);
 114 }
 115
 116 /** Event handler for the USB_DeviceEnumerationFailed event. This indicates that a problem occurred while
 117  *  enumerating an attached USB device.
 118  */
 119 void EVENT_USB_Host_DeviceEnumerationFailed(const uint8_t ErrorCode,
 120                                             const uint8_t SubErrorCode)
 121 {
 122         printf_P(PSTR(ESC_FG_RED "Dev Enum Error\r\n"
 123                                  " -- Error Code %d\r\n"
 124                                  " -- Sub Error Code %d\r\n"
 125                                  " -- In State %d\r\n" ESC_FG_WHITE), ErrorCode, SubErrorCode, USB_HostState);
 126
 127         LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 128 }
 129
 130 void Audio_Task(void)
 131 {
 132         uint8_t ErrorCode;
 133
 134         switch (USB_HostState)
 135         {
 136                 case HOST_STATE_Addressed:
 137                         puts_P(PSTR("Getting Config Data.\r\n"));
 138
 139                         /* Get and process the configuration descriptor data */
 140                         if ((ErrorCode = ProcessConfigurationDescriptor()) != SuccessfulConfigRead)
 141                         {
 142                                 if (ErrorCode == ControlError)
 143                                   puts_P(PSTR(ESC_FG_RED "Control Error (Get Configuration).\r\n"));
 144                                 else
 145                                   puts_P(PSTR(ESC_FG_RED "Invalid Device.\r\n"));
 146
 147                                 printf_P(PSTR(" -- Error Code: %d\r\n" ESC_FG_WHITE), ErrorCode);
 148
 149                                 /* Indicate error status */
 150                                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 151
 152                                 /* Wait until USB device disconnected */
 153                                 USB_HostState = HOST_STATE_WaitForDeviceRemoval;
 154                                 break;
 155                         }
 156
 157                         /* Set the device configuration to the first configuration (rarely do devices use multiple configurations) */
 158                         if ((ErrorCode = USB_Host_SetDeviceConfiguration(1)) != HOST_SENDCONTROL_Successful)
 159                         {
 160                                 printf_P(PSTR(ESC_FG_RED "Control Error (Set Configuration).\r\n"
 161                                                          " -- Error Code: %d\r\n" ESC_FG_WHITE), ErrorCode);
 162
 163                                 /* Indicate error status */
 164                                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 165
 166                                 /* Wait until USB device disconnected */
 167                                 USB_HostState = HOST_STATE_WaitForDeviceRemoval;
 168                                 break;
 169                         }
 170
 171                         if ((ErrorCode = USB_Host_SetInterfaceAltSetting(StreamingInterfaceIndex,
 172                                                                          StreamingInterfaceAltSetting)) != HOST_SENDCONTROL_Successful)
 173                         {
 174                                 printf_P(PSTR(ESC_FG_RED "Could not set alternative streaming interface setting.\r\n"
 175                                                          " -- Error Code: %d\r\n" ESC_FG_WHITE), ErrorCode);
 176
 177                                 /* Indicate error status */
 178                                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 179
 180                                 /* Wait until USB device disconnected */
 181                                 USB_HostState = HOST_STATE_WaitForDeviceRemoval;
 182                                 break;
 183                         }
 184
 185                         USB_ControlRequest = (USB_Request_Header_t)
 186                                 {
 187                                         .bmRequestType = (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_ENDPOINT),
 188                                         .bRequest      = AUDIO_REQ_SetCurrent,
 189                                         .wValue        = (AUDIO_EPCONTROL_SamplingFreq << 8),
 190                                         .wIndex        = StreamingEndpointAddress,
 191                                         .wLength       = sizeof(USB_Audio_SampleFreq_t),
 192                                 };
 193
 194                         USB_Audio_SampleFreq_t SampleRate = AUDIO_SAMPLE_FREQ(48000);
 195
 196                         /* Select the control pipe for the request transfer */
 197                         Pipe_SelectPipe(PIPE_CONTROLPIPE);
 198
 199                         /* Set the sample rate on the streaming interface endpoint */
 200                         if ((ErrorCode = USB_Host_SendControlRequest(&SampleRate)) != HOST_SENDCONTROL_Successful)
 201                         {
 202                                 /* Indicate error status */
 203                                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 204
 205                                 /* Wait until USB device disconnected */
 206                                 USB_HostState = HOST_STATE_WaitForDeviceRemoval;
 207                                 break;
 208                         }
 209
 210                         /* Sample reload timer initialization */
 211                         TIMSK0  = (1 << OCIE0A);
 212                         OCR0A   = ((F_CPU / 8 / 48000) - 1);
 213                         TCCR0A  = (1 << WGM01);  // CTC mode
 214                         TCCR0B  = (1 << CS01);   // Fcpu/8 speed
 215
 216                         puts_P(PSTR("Speaker Enumerated.\r\n"));
 217
 218                         USB_HostState = HOST_STATE_Configured;
 219                         break;
 220                 case HOST_STATE_Configured:
 221                         /* Do nothing - audio stream is handled by the timer interrupt routine */
 222                         break;
 223         }
 224 }
 225
 226 /** ISR to handle the reloading of the endpoint with the next sample. */
 227 ISR(TIMER0_COMPA_vect, ISR_BLOCK)
 228 {
 229         uint8_t PrevPipe = Pipe_GetCurrentPipe();
 230
 231         Pipe_SelectPipe(AUDIO_DATA_OUT_PIPE);
 232         Pipe_Unfreeze();
 233
 234         /* Check if the current pipe can be written to (device ready for more data) */
 235         if (Pipe_IsOUTReady())
 236         {
 237                 static uint8_t SquareWaveSampleCount;
 238                 static int16_t CurrentWaveValue;
 239
 240                 if (SquareWaveSampleCount++ == 0xFF)
 241                   CurrentWaveValue ^= 0x8000;
 242
 243                 /* Only generate audio if the board button is being pressed */
 244                 int16_t Sample_16Bit = (Buttons_GetStatus() & BUTTONS_BUTTON1) ? CurrentWaveValue : 0;
 245
 246                 Pipe_Write_16_LE(Sample_16Bit);
 247                 Pipe_Write_16_LE(Sample_16Bit);
 248
 249                 if (!(Pipe_IsReadWriteAllowed()))
 250                   Pipe_ClearOUT();
 251         }
 252
 253         Pipe_Freeze();
 254         Pipe_SelectPipe(PrevPipe);
 255 }