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 LineCoding = { .BaudRateBPS = 9600,
  49                                  .CharFormat  = OneStopBit,
  50                                  .ParityType  = Parity_None,
  51                                  .DataBits    = 8            };
  52
  53 /** Indicates if the host has set the device line encoding. Until the line encoding is set by the host, the device should
  54  *  not attempt to send any bytes.
  55  */
  56 bool LineEncodingSet = false;
  57
  58
  59 #if 0
  60 /* NOTE: Here you can set up a standard stream using the created virtual serial port, so that the standard stream functions in
  61  *       <stdio.h> can be used on the virtual serial port (e.g. fprintf(&USBSerial, "Test"); to print a string).
  62  */
  63
  64 static int CDC_putchar(char c, FILE *stream)
  65 {
  66         Endpoint_SelectEndpoint(CDC_TX_EPNUM);
  67
  68         if (!(LineEncodingSet))
  69           return -1;
  70
  71         while (!(Endpoint_IsReadWriteAllowed()))
  72         {
  73                 if (USB_DeviceState != DEVICE_STATE_Configured)
  74                   return -1;
  75         }
  76
  77         Endpoint_Write_Byte(c);
  78         Endpoint_ClearIN();
  79
  80         return 0;
  81 }
  82
  83 static int CDC_getchar(FILE *stream)
  84 {
  85         int c;
  86
  87         if (!(LineEncodingSet))
  88           return -1;
  89
  90         Endpoint_SelectEndpoint(CDC_RX_EPNUM);
  91
  92         for (;;)
  93         {
  94                 while (!(Endpoint_IsReadWriteAllowed()))
  95                 {
  96                         if (USB_DeviceState != DEVICE_STATE_Configured)
  97                           return -1;
  98                 }
  99
 100                 if (!(Endpoint_BytesInEndpoint()))
 101                 {
 102                         Endpoint_ClearOUT();
 103                 }
 104                 else
 105                 {
 106                         c = Endpoint_Read_Byte();
 107                         break;
 108                 }
 109         }
 110
 111         return c;
 112 }
 113
 114 static FILE USBSerial = FDEV_SETUP_STREAM(CDC_putchar, CDC_getchar, _FDEV_SETUP_RW);
 115 #endif
 116
 117 /** Main program entry point. This routine contains the overall program flow, including initial
 118  *  setup of all components and the main program loop.
 119  */
 120 int main(void)
 121 {
 122         SetupHardware();
 123
 124         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 125
 126         for (;;)
 127         {
 128                 CDC_Task();
 129                 USB_USBTask();
 130         }
 131 }
 132
 133 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 134 void SetupHardware(void)
 135 {
 136         /* Disable watchdog if enabled by bootloader/fuses */
 137         MCUSR &= ~(1 << WDRF);
 138         wdt_disable();
 139
 140         /* Disable clock division */
 141         clock_prescale_set(clock_div_1);
 142
 143         /* Hardware Initialization */
 144         Joystick_Init();
 145         LEDs_Init();
 146         USB_Init();
 147 }
 148
 149 /** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs and
 150  *  starts the library USB task to begin the enumeration and USB management process.
 151  */
 152 void EVENT_USB_Connect(void)
 153 {
 154         /* Indicate USB enumerating */
 155         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 156 }
 157
 158 /** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
 159  *  the status LEDs and stops the USB management and CDC management tasks.
 160  */
 161 void EVENT_USB_Disconnect(void)
 162 {
 163         /* Indicate USB not ready */
 164         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 165 }
 166
 167 /** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
 168  *  of the USB device after enumeration - the device endpoints are configured and the CDC management task started.
 169  */
 170 void EVENT_USB_ConfigurationChanged(void)
 171 {
 172         /* Indicate USB connected and ready */
 173         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 174
 175         /* Setup CDC Notification, Rx and Tx Endpoints */
 176         if (!(Endpoint_ConfigureEndpoint(CDC_NOTIFICATION_EPNUM, EP_TYPE_INTERRUPT,
 177                                              ENDPOINT_DIR_IN, CDC_NOTIFICATION_EPSIZE,
 178                                          ENDPOINT_BANK_SINGLE)))
 179         {
 180                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 181         }
 182
 183         if (!(Endpoint_ConfigureEndpoint(CDC_TX_EPNUM, EP_TYPE_BULK,
 184                                              ENDPOINT_DIR_IN, CDC_TXRX_EPSIZE,
 185                                          ENDPOINT_BANK_SINGLE)))
 186         {
 187                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 188         }
 189
 190         if (!(Endpoint_ConfigureEndpoint(CDC_RX_EPNUM, EP_TYPE_BULK,
 191                                              ENDPOINT_DIR_OUT, CDC_TXRX_EPSIZE,
 192                                          ENDPOINT_BANK_SINGLE)))
 193         {
 194                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 195         }
 196 }
 197
 198 /** Event handler for the USB_UnhandledControlPacket event. This is used to catch standard and class specific
 199  *  control requests that are not handled internally by the USB library (including the CDC control commands,
 200  *  which are all issued via the control endpoint), so that they can be handled appropriately for the application.
 201  */
 202 void EVENT_USB_UnhandledControlPacket(void)
 203 {
 204         uint8_t* LineCodingData = (uint8_t*)&LineCoding;
 205
 206         /* Process CDC specific control requests */
 207         switch (USB_ControlRequest.bRequest)
 208         {
 209                 case REQ_GetLineEncoding:
 210                         if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
 211                         {
 212                                 /* Acknowledge the SETUP packet, ready for data transfer */
 213                                 Endpoint_ClearSETUP();
 214
 215                                 /* Write the line coding data to the control endpoint */
 216                                 Endpoint_Write_Control_Stream_LE(LineCodingData, sizeof(CDC_Line_Coding_t));
 217
 218                                 /* Finalize the stream transfer to send the last packet or clear the host abort */
 219                                 Endpoint_ClearOUT();
 220                         }
 221
 222                         break;
 223                 case REQ_SetLineEncoding:
 224                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 225                         {
 226                                 /* Acknowledge the SETUP packet, ready for data transfer */
 227                                 Endpoint_ClearSETUP();
 228
 229                                 /* Read the line coding data in from the host into the global struct */
 230                                 Endpoint_Read_Control_Stream_LE(LineCodingData, sizeof(CDC_Line_Coding_t));
 231
 232                                 /* Indicate that the line encoding has been set, and the device may now send data */
 233                                 LineEncodingSet = true;
 234
 235                                 /* Finalize the stream transfer to clear the last packet from the host */
 236                                 Endpoint_ClearIN();
 237                         }
 238
 239                         break;
 240                 case REQ_SetControlLineState:
 241                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 242                         {
 243                                 /* Acknowledge the SETUP packet, ready for data transfer */
 244                                 Endpoint_ClearSETUP();
 245
 246                                 /* NOTE: Here you can read in the line state mask from the host, to get the current state of the output handshake
 247                                          lines. The mask is read in from the wValue parameter in USB_ControlRequest, and can be masked against the
 248                                                  CONTROL_LINE_OUT_* masks to determine the RTS and DTR line states using the following code:
 249                                 */
 250
 251                                 Endpoint_ClearStatusStage();
 252                         }
 253
 254                         break;
 255         }
 256 }
 257
 258 /** Function to manage CDC data transmission and reception to and from the host. */
 259 void CDC_Task(void)
 260 {
 261         char*       ReportString    = NULL;
 262         uint8_t     JoyStatus_LCL   = Joystick_GetStatus();
 263         static bool ActionSent      = false;
 264         char*       JoystickStrings[] =
 265                                         {
 266                                                 "Joystick Up\r\n",
 267                                                 "Joystick Down\r\n",
 268                                                 "Joystick Left\r\n",
 269                                                 "Joystick Right\r\n",
 270                                                 "Joystick Pressed\r\n",
 271                                         };
 272
 273         /* Device must be connected and configured for the task to run */
 274         if (USB_DeviceState != DEVICE_STATE_Configured)
 275           return;
 276
 277 #if 0
 278         /* NOTE: Here you can use the notification endpoint to send back line state changes to the host, for the special RS-232
 279          *       handshake signal lines (and some error states), via the CONTROL_LINE_IN_* masks and the following code:
 280          */
 281         USB_Notification_Header_t Notification = (USB_Notification_Header_t)
 282                 {
 283                         .NotificationType = (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE),
 284                         .Notification     = NOTIF_SerialState,
 285                         .wValue           = 0,
 286                         .wIndex           = 0,
 287                         .wLength          = sizeof(uint16_t),
 288                 };
 289
 290         uint16_t LineStateMask;
 291
 292         // Set LineStateMask here to a mask of CONTROL_LINE_IN_* masks to set the input handshake line states to send to the host
 293
 294         Endpoint_SelectEndpoint(CDC_NOTIFICATION_EPNUM);
 295         Endpoint_Write_Stream_LE(&Notification, sizeof(Notification));
 296         Endpoint_Write_Stream_LE(&LineStateMask, sizeof(LineStateMask));
 297         Endpoint_ClearIN();
 298 #endif
 299
 300         /* Determine if a joystick action has occurred */
 301         if (JoyStatus_LCL & JOY_UP)
 302           ReportString = JoystickStrings[0];
 303         else if (JoyStatus_LCL & JOY_DOWN)
 304           ReportString = JoystickStrings[1];
 305         else if (JoyStatus_LCL & JOY_LEFT)
 306           ReportString = JoystickStrings[2];
 307         else if (JoyStatus_LCL & JOY_RIGHT)
 308           ReportString = JoystickStrings[3];
 309         else if (JoyStatus_LCL & JOY_PRESS)
 310           ReportString = JoystickStrings[4];
 311
 312         /* Flag management - Only allow one string to be sent per action */
 313         if (ReportString == NULL)
 314         {
 315                 ActionSent = false;
 316         }
 317         else if ((ActionSent == false) && LineEncodingSet)
 318         {
 319                 ActionSent = true;
 320
 321                 /* Select the Serial Tx Endpoint */
 322                 Endpoint_SelectEndpoint(CDC_TX_EPNUM);
 323
 324                 /* Write the String to the Endpoint */
 325                 Endpoint_Write_Stream_LE(ReportString, strlen(ReportString));
 326
 327                 /* Remember if the packet to send completely fills the endpoint */
 328                 bool IsFull = (Endpoint_BytesInEndpoint() == CDC_TXRX_EPSIZE);
 329
 330                 /* Finalize the stream transfer to send the last packet */
 331                 Endpoint_ClearIN();
 332
 333                 /* If the last packet filled the endpoint, send an empty packet to release the buffer on
 334                  * the receiver (otherwise all data will be cached until a non-full packet is received) */
 335                 if (IsFull)
 336                 {
 337                         /* Wait until the endpoint is ready for another packet */
 338                         while (!(Endpoint_IsINReady()))
 339                         {
 340                                 if (USB_DeviceState == DEVICE_STATE_Unattached)
 341                                   return;
 342                         }
 343
 344                         /* Send an empty packet to ensure that the host does not buffer data sent to it */
 345                         Endpoint_ClearIN();
 346                 }
 347         }
 348
 349         /* Select the Serial Rx Endpoint */
 350         Endpoint_SelectEndpoint(CDC_RX_EPNUM);
 351
 352         /* Throw away any received data from the host */
 353         if (Endpoint_IsOUTReceived())
 354           Endpoint_ClearOUT();
 355 }