Demos/Device/LowLevel/CDC/CDC.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2009.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2009  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, and distribute this software
  13   and its documentation for any purpose and without fee is hereby
  14   granted, provided that the above copyright notice appear in all
  15   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 CDC demo. This file contains the main tasks of the demo and
  34  *  is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "CDC.h"
  38
  39 /* Globals: */
  40 /** Contains the current baud rate and other settings of the virtual serial port. While this demo does not use
  41  *  the physical USART and thus does not use these settings, they must still be retained and returned to the host
  42  *  upon request or the host will assume the device is non-functional.
  43  *
  44  *  These values are set by the host via a class-specific request, however they are not required to be used accurately.
  45  *  It is possible to completely ignore these value or use other settings as the host is completely unaware of the physical
  46  *  serial link characteristics and instead sends and receives data in endpoint streams.
  47  */
  48 CDC_Line_Coding_t LineEncoding = { .BaudRateBPS = 0,
  49                                    .CharFormat  = OneStopBit,
  50                                    .ParityType  = Parity_None,
  51                                    .DataBits    = 8            };
  52
  53 #if 0
  54 /* NOTE: Here you can set up a standard stream using the created virtual serial port, so that the standard stream functions in
  55  *       <stdio.h> can be used on the virtual serial port (e.g. fprintf(&USBSerial, "Test"); to print a string).
  56  */
  57
  58 static int CDC_putchar(char c, FILE *stream)
  59 {
  60         Endpoint_SelectEndpoint(CDC_TX_EPNUM);
  61
  62         if (!(LineEncoding.BaudRateBPS))
  63           return -1;
  64
  65         while (!(Endpoint_IsReadWriteAllowed()))
  66         {
  67                 if (USB_DeviceState != DEVICE_STATE_Configured)
  68                   return -1;
  69         }
  70
  71         Endpoint_Write_Byte(c);
  72         Endpoint_ClearIN();
  73
  74         return 0;
  75 }
  76
  77 static int CDC_getchar(FILE *stream)
  78 {
  79         int c;
  80
  81         if (!(LineEncoding.BaudRateBPS))
  82           return -1;
  83
  84         Endpoint_SelectEndpoint(CDC_RX_EPNUM);
  85
  86         for (;;)
  87         {
  88                 while (!(Endpoint_IsReadWriteAllowed()))
  89                 {
  90                         if (USB_DeviceState != DEVICE_STATE_Configured)
  91                           return -1;
  92                 }
  93
  94                 if (!(Endpoint_BytesInEndpoint()))
  95                 {
  96                         Endpoint_ClearOUT();
  97                 }
  98                 else
  99                 {
 100                         c = Endpoint_Read_Byte();
 101                         break;
 102                 }
 103         }
 104
 105         return c;
 106 }
 107
 108 static FILE USBSerial = FDEV_SETUP_STREAM(CDC_putchar, CDC_getchar, _FDEV_SETUP_RW);
 109 #endif
 110
 111 /** Main program entry point. This routine contains the overall program flow, including initial
 112  *  setup of all components and the main program loop.
 113  */
 114 int main(void)
 115 {
 116         SetupHardware();
 117
 118         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 119
 120         for (;;)
 121         {
 122                 CDC_Task();
 123                 USB_USBTask();
 124         }
 125 }
 126
 127 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 128 void SetupHardware(void)
 129 {
 130         /* Disable watchdog if enabled by bootloader/fuses */
 131         MCUSR &= ~(1 << WDRF);
 132         wdt_disable();
 133
 134         /* Disable clock division */
 135         clock_prescale_set(clock_div_1);
 136
 137         /* Hardware Initialization */
 138         Joystick_Init();
 139         LEDs_Init();
 140         USB_Init();
 141 }
 142
 143 /** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs and
 144  *  starts the library USB task to begin the enumeration and USB management process.
 145  */
 146 void EVENT_USB_Device_Connect(void)
 147 {
 148         /* Indicate USB enumerating */
 149         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 150 }
 151
 152 /** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
 153  *  the status LEDs and stops the USB management and CDC management tasks.
 154  */
 155 void EVENT_USB_Device_Disconnect(void)
 156 {
 157         /* Indicate USB not ready */
 158         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 159 }
 160
 161 /** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
 162  *  of the USB device after enumeration - the device endpoints are configured and the CDC management task started.
 163  */
 164 void EVENT_USB_Device_ConfigurationChanged(void)
 165 {
 166         /* Indicate USB connected and ready */
 167         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 168
 169         /* Setup CDC Notification, Rx and Tx Endpoints */
 170         if (!(Endpoint_ConfigureEndpoint(CDC_NOTIFICATION_EPNUM, EP_TYPE_INTERRUPT,
 171                                              ENDPOINT_DIR_IN, CDC_NOTIFICATION_EPSIZE,
 172                                          ENDPOINT_BANK_SINGLE)))
 173         {
 174                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 175         }
 176
 177         if (!(Endpoint_ConfigureEndpoint(CDC_TX_EPNUM, EP_TYPE_BULK,
 178                                              ENDPOINT_DIR_IN, CDC_TXRX_EPSIZE,
 179                                          ENDPOINT_BANK_SINGLE)))
 180         {
 181                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 182         }
 183
 184         if (!(Endpoint_ConfigureEndpoint(CDC_RX_EPNUM, EP_TYPE_BULK,
 185                                              ENDPOINT_DIR_OUT, CDC_TXRX_EPSIZE,
 186                                          ENDPOINT_BANK_SINGLE)))
 187         {
 188                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 189         }
 190
 191         /* Reset line encoding baud rate so that the host knows to send new values */
 192         LineEncoding.BaudRateBPS = 0;
 193 }
 194
 195 /** Event handler for the USB_UnhandledControlRequest event. This is used to catch standard and class specific
 196  *  control requests that are not handled internally by the USB library (including the CDC control commands,
 197  *  which are all issued via the control endpoint), so that they can be handled appropriately for the application.
 198  */
 199 void EVENT_USB_Device_UnhandledControlRequest(void)
 200 {
 201         /* Process CDC specific control requests */
 202         switch (USB_ControlRequest.bRequest)
 203         {
 204                 case REQ_GetLineEncoding:
 205                         if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
 206                         {
 207                                 /* Acknowledge the SETUP packet, ready for data transfer */
 208                                 Endpoint_ClearSETUP();
 209
 210                                 /* Write the line coding data to the control endpoint */
 211                                 Endpoint_Write_Control_Stream_LE(&LineEncoding, sizeof(CDC_Line_Coding_t));
 212
 213                                 /* Finalize the stream transfer to send the last packet or clear the host abort */
 214                                 Endpoint_ClearOUT();
 215                         }
 216
 217                         break;
 218                 case REQ_SetLineEncoding:
 219                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 220                         {
 221                                 /* Acknowledge the SETUP packet, ready for data transfer */
 222                                 Endpoint_ClearSETUP();
 223
 224                                 /* Read the line coding data in from the host into the global struct */
 225                                 Endpoint_Read_Control_Stream_LE(&LineEncoding, sizeof(CDC_Line_Coding_t));
 226
 227                                 /* Finalize the stream transfer to clear the last packet from the host */
 228                                 Endpoint_ClearIN();
 229                         }
 230
 231                         break;
 232                 case REQ_SetControlLineState:
 233                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 234                         {
 235                                 /* Acknowledge the SETUP packet, ready for data transfer */
 236                                 Endpoint_ClearSETUP();
 237
 238                                 /* NOTE: Here you can read in the line state mask from the host, to get the current state of the output handshake
 239                                          lines. The mask is read in from the wValue parameter in USB_ControlRequest, and can be masked against the
 240                                                  CONTROL_LINE_OUT_* masks to determine the RTS and DTR line states using the following code:
 241                                 */
 242
 243                                 Endpoint_ClearStatusStage();
 244                         }
 245
 246                         break;
 247         }
 248 }
 249
 250 /** Function to manage CDC data transmission and reception to and from the host. */
 251 void CDC_Task(void)
 252 {
 253         char*       ReportString    = NULL;
 254         uint8_t     JoyStatus_LCL   = Joystick_GetStatus();
 255         static bool ActionSent      = false;
 256         char*       JoystickStrings[] =
 257                                         {
 258                                                 "Joystick Up\r\n",
 259                                                 "Joystick Down\r\n",
 260                                                 "Joystick Left\r\n",
 261                                                 "Joystick Right\r\n",
 262                                                 "Joystick Pressed\r\n",
 263                                         };
 264
 265         /* Device must be connected and configured for the task to run */
 266         if (USB_DeviceState != DEVICE_STATE_Configured)
 267           return;
 268
 269 #if 0
 270         /* NOTE: Here you can use the notification endpoint to send back line state changes to the host, for the special RS-232
 271          *       handshake signal lines (and some error states), via the CONTROL_LINE_IN_* masks and the following code:
 272          */
 273         USB_Notification_Header_t Notification = (USB_Notification_Header_t)
 274                 {
 275                         .NotificationType = (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE),
 276                         .Notification     = NOTIF_SerialState,
 277                         .wValue           = 0,
 278                         .wIndex           = 0,
 279                         .wLength          = sizeof(uint16_t),
 280                 };
 281
 282         uint16_t LineStateMask;
 283
 284         // Set LineStateMask here to a mask of CONTROL_LINE_IN_* masks to set the input handshake line states to send to the host
 285
 286         Endpoint_SelectEndpoint(CDC_NOTIFICATION_EPNUM);
 287         Endpoint_Write_Stream_LE(&Notification, sizeof(Notification));
 288         Endpoint_Write_Stream_LE(&LineStateMask, sizeof(LineStateMask));
 289         Endpoint_ClearIN();
 290 #endif
 291
 292         /* Determine if a joystick action has occurred */
 293         if (JoyStatus_LCL & JOY_UP)
 294           ReportString = JoystickStrings[0];
 295         else if (JoyStatus_LCL & JOY_DOWN)
 296           ReportString = JoystickStrings[1];
 297         else if (JoyStatus_LCL & JOY_LEFT)
 298           ReportString = JoystickStrings[2];
 299         else if (JoyStatus_LCL & JOY_RIGHT)
 300           ReportString = JoystickStrings[3];
 301         else if (JoyStatus_LCL & JOY_PRESS)
 302           ReportString = JoystickStrings[4];
 303
 304         /* Flag management - Only allow one string to be sent per action */
 305         if (ReportString == NULL)
 306         {
 307                 ActionSent = false;
 308         }
 309         else if ((ActionSent == false) && LineEncoding.BaudRateBPS)
 310         {
 311                 ActionSent = true;
 312
 313                 /* Select the Serial Tx Endpoint */
 314                 Endpoint_SelectEndpoint(CDC_TX_EPNUM);
 315
 316                 /* Write the String to the Endpoint */
 317                 Endpoint_Write_Stream_LE(ReportString, strlen(ReportString));
 318
 319                 /* Remember if the packet to send completely fills the endpoint */
 320                 bool IsFull = (Endpoint_BytesInEndpoint() == CDC_TXRX_EPSIZE);
 321
 322                 /* Finalize the stream transfer to send the last packet */
 323                 Endpoint_ClearIN();
 324
 325                 /* If the last packet filled the endpoint, send an empty packet to release the buffer on
 326                  * the receiver (otherwise all data will be cached until a non-full packet is received) */
 327                 if (IsFull)
 328                 {
 329                         /* Wait until the endpoint is ready for another packet */
 330                         while (!(Endpoint_IsINReady()))
 331                         {
 332                                 if (USB_DeviceState == DEVICE_STATE_Unattached)
 333                                   return;
 334                         }
 335
 336                         /* Send an empty packet to ensure that the host does not buffer data sent to it */
 337                         Endpoint_ClearIN();
 338                 }
 339         }
 340
 341         /* Select the Serial Rx Endpoint */
 342         Endpoint_SelectEndpoint(CDC_RX_EPNUM);
 343
 344         /* Throw away any received data from the host */
 345         if (Endpoint_IsOUTReceived())
 346           Endpoint_ClearOUT();
 347 }