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