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