Demos/Device/LowLevel/VirtualSerial/VirtualSerial.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 VirtualSerial demo. This file contains the main tasks of the demo and
  34  *  is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "VirtualSerial.h"
  38
  39 /** Contains the current baud rate and other settings of the virtual serial port. While this demo does not use
  40  *  the physical USART and thus does not use these settings, they must still be retained and returned to the host
  41  *  upon request or the host will assume the device is non-functional.
  42  *
  43  *  These values are set by the host via a class-specific request, however they are not required to be used accurately.
  44  *  It is possible to completely ignore these value or use other settings as the host is completely unaware of the physical
  45  *  serial link characteristics and instead sends and receives data in endpoint streams.
  46  */
  47 CDC_LineEncoding_t LineEncoding = { .BaudRateBPS = 0,
  48                                     .CharFormat  = CDC_LINEENCODING_OneStopBit,
  49                                     .ParityType  = CDC_PARITY_None,
  50                                     .DataBits    = 8                            };
  51
  52 /** Main program entry point. This routine contains the overall program flow, including initial
  53  *  setup of all components and the main program loop.
  54  */
  55 int main(void)
  56 {
  57         SetupHardware();
  58
  59         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  60         sei();
  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_Device_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_Device_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_Device_ConfigurationChanged(void)
 107 {
 108         bool ConfigSuccess = true;
 109
 110         /* Setup CDC Data Endpoints */
 111         ConfigSuccess &= Endpoint_ConfigureEndpoint(CDC_NOTIFICATION_EPNUM, EP_TYPE_INTERRUPT, ENDPOINT_DIR_IN,
 112                                                     CDC_NOTIFICATION_EPSIZE, ENDPOINT_BANK_SINGLE);
 113         ConfigSuccess &= Endpoint_ConfigureEndpoint(CDC_TX_EPNUM, EP_TYPE_BULK, ENDPOINT_DIR_IN,
 114                                                     CDC_TXRX_EPSIZE, ENDPOINT_BANK_SINGLE);
 115         ConfigSuccess &= Endpoint_ConfigureEndpoint(CDC_RX_EPNUM, EP_TYPE_BULK, ENDPOINT_DIR_OUT,
 116                                                     CDC_TXRX_EPSIZE, ENDPOINT_BANK_SINGLE);
 117
 118         /* Reset line encoding baud rate so that the host knows to send new values */
 119         LineEncoding.BaudRateBPS = 0;
 120
 121         /* Indicate endpoint configuration success or failure */
 122         LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
 123 }
 124
 125 /** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to
 126  *  the device from the USB host before passing along unhandled control requests to the library for processing
 127  *  internally.
 128  */
 129 void EVENT_USB_Device_ControlRequest(void)
 130 {
 131         /* Process CDC specific control requests */
 132         switch (USB_ControlRequest.bRequest)
 133         {
 134                 case CDC_REQ_GetLineEncoding:
 135                         if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
 136                         {
 137                                 Endpoint_ClearSETUP();
 138
 139                                 /* Write the line coding data to the control endpoint */
 140                                 Endpoint_Write_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t));
 141                                 Endpoint_ClearOUT();
 142                         }
 143
 144                         break;
 145                 case CDC_REQ_SetLineEncoding:
 146                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 147                         {
 148                                 Endpoint_ClearSETUP();
 149
 150                                 /* Read the line coding data in from the host into the global struct */
 151                                 Endpoint_Read_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t));
 152                                 Endpoint_ClearIN();
 153                         }
 154
 155                         break;
 156                 case CDC_REQ_SetControlLineState:
 157                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 158                         {
 159                                 Endpoint_ClearSETUP();
 160                                 Endpoint_ClearStatusStage();
 161
 162                                 /* NOTE: Here you can read in the line state mask from the host, to get the current state of the output handshake
 163                                          lines. The mask is read in from the wValue parameter in USB_ControlRequest, and can be masked against the
 164                                                  CONTROL_LINE_OUT_* masks to determine the RTS and DTR line states using the following code:
 165                                 */
 166                         }
 167
 168                         break;
 169         }
 170 }
 171
 172 /** Function to manage CDC data transmission and reception to and from the host. */
 173 void CDC_Task(void)
 174 {
 175         char*       ReportString    = NULL;
 176         uint8_t     JoyStatus_LCL   = Joystick_GetStatus();
 177         static bool ActionSent      = false;
 178
 179         /* Device must be connected and configured for the task to run */
 180         if (USB_DeviceState != DEVICE_STATE_Configured)
 181           return;
 182
 183         /* Determine if a joystick action has occurred */
 184         if (JoyStatus_LCL & JOY_UP)
 185           ReportString = "Joystick Up\r\n";
 186         else if (JoyStatus_LCL & JOY_DOWN)
 187           ReportString = "Joystick Down\r\n";
 188         else if (JoyStatus_LCL & JOY_LEFT)
 189           ReportString = "Joystick Left\r\n";
 190         else if (JoyStatus_LCL & JOY_RIGHT)
 191           ReportString = "Joystick Right\r\n";
 192         else if (JoyStatus_LCL & JOY_PRESS)
 193           ReportString = "Joystick Pressed\r\n";
 194         else
 195           ActionSent = false;
 196
 197         /* Flag management - Only allow one string to be sent per action */
 198         if ((ReportString != NULL) && (ActionSent == false) && LineEncoding.BaudRateBPS)
 199         {
 200                 ActionSent = true;
 201
 202                 /* Select the Serial Tx Endpoint */
 203                 Endpoint_SelectEndpoint(CDC_TX_EPNUM);
 204
 205                 /* Write the String to the Endpoint */
 206                 Endpoint_Write_Stream_LE(ReportString, strlen(ReportString), NULL);
 207
 208                 /* Remember if the packet to send completely fills the endpoint */
 209                 bool IsFull = (Endpoint_BytesInEndpoint() == CDC_TXRX_EPSIZE);
 210
 211                 /* Finalize the stream transfer to send the last packet */
 212                 Endpoint_ClearIN();
 213
 214                 /* If the last packet filled the endpoint, send an empty packet to release the buffer on
 215                  * the receiver (otherwise all data will be cached until a non-full packet is received) */
 216                 if (IsFull)
 217                 {
 218                         /* Wait until the endpoint is ready for another packet */
 219                         Endpoint_WaitUntilReady();
 220
 221                         /* Send an empty packet to ensure that the host does not buffer data sent to it */
 222                         Endpoint_ClearIN();
 223                 }
 224         }
 225
 226         /* Select the Serial Rx Endpoint */
 227         Endpoint_SelectEndpoint(CDC_RX_EPNUM);
 228
 229         /* Throw away any received data from the host */
 230         if (Endpoint_IsOUTReceived())
 231           Endpoint_ClearOUT();
 232 }
 233