Demos/Device/LowLevel/VirtualSerial/VirtualSerial.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2016.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2016  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 disclaims 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 static CDC_LineEncoding_t LineEncoding = { .BaudRateBPS = 0,
  48                                            .CharFormat  = CDC_LINEENCODING_OneStopBit,
  49                                            .ParityType  = CDC_PARITY_None,
  50                                            .DataBits    = 8                            };
  51
  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         GlobalInterruptEnable();
  62
  63         for (;;)
  64         {
  65                 CDC_Task();
  66                 USB_USBTask();
  67         }
  68 }
  69
  70 /** Configures the board hardware and chip peripherals for the demo's functionality. */
  71 void SetupHardware(void)
  72 {
  73 #if (ARCH == ARCH_AVR8)
  74         /* Disable watchdog if enabled by bootloader/fuses */
  75         MCUSR &= ~(1 << WDRF);
  76         wdt_disable();
  77
  78         /* Disable clock division */
  79         clock_prescale_set(clock_div_1);
  80 #elif (ARCH == ARCH_XMEGA)
  81         /* Start the PLL to multiply the 2MHz RC oscillator to 32MHz and switch the CPU core to run from it */
  82         XMEGACLK_StartPLL(CLOCK_SRC_INT_RC2MHZ, 2000000, F_CPU);
  83         XMEGACLK_SetCPUClockSource(CLOCK_SRC_PLL);
  84
  85         /* Start the 32MHz internal RC oscillator and start the DFLL to increase it to 48MHz using the USB SOF as a reference */
  86         XMEGACLK_StartInternalOscillator(CLOCK_SRC_INT_RC32MHZ);
  87         XMEGACLK_StartDFLL(CLOCK_SRC_INT_RC32MHZ, DFLL_REF_INT_USBSOF, F_USB);
  88
  89         PMIC.CTRL = PMIC_LOLVLEN_bm | PMIC_MEDLVLEN_bm | PMIC_HILVLEN_bm;
  90 #endif
  91
  92         /* Hardware Initialization */
  93         Joystick_Init();
  94         LEDs_Init();
  95         USB_Init();
  96 }
  97
  98 /** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs and
  99  *  starts the library USB task to begin the enumeration and USB management process.
 100  */
 101 void EVENT_USB_Device_Connect(void)
 102 {
 103         /* Indicate USB enumerating */
 104         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 105 }
 106
 107 /** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
 108  *  the status LEDs and stops the USB management and CDC management tasks.
 109  */
 110 void EVENT_USB_Device_Disconnect(void)
 111 {
 112         /* Indicate USB not ready */
 113         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 114 }
 115
 116 /** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
 117  *  of the USB device after enumeration - the device endpoints are configured and the CDC management task started.
 118  */
 119 void EVENT_USB_Device_ConfigurationChanged(void)
 120 {
 121         bool ConfigSuccess = true;
 122
 123         /* Setup CDC Data Endpoints */
 124         ConfigSuccess &= Endpoint_ConfigureEndpoint(CDC_NOTIFICATION_EPADDR, EP_TYPE_INTERRUPT, CDC_NOTIFICATION_EPSIZE, 1);
 125         ConfigSuccess &= Endpoint_ConfigureEndpoint(CDC_TX_EPADDR, EP_TYPE_BULK, CDC_TXRX_EPSIZE, 1);
 126         ConfigSuccess &= Endpoint_ConfigureEndpoint(CDC_RX_EPADDR, EP_TYPE_BULK,  CDC_TXRX_EPSIZE, 1);
 127
 128         /* Reset line encoding baud rate so that the host knows to send new values */
 129         LineEncoding.BaudRateBPS = 0;
 130
 131         /* Indicate endpoint configuration success or failure */
 132         LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
 133 }
 134
 135 /** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to
 136  *  the device from the USB host before passing along unhandled control requests to the library for processing
 137  *  internally.
 138  */
 139 void EVENT_USB_Device_ControlRequest(void)
 140 {
 141         /* Process CDC specific control requests */
 142         switch (USB_ControlRequest.bRequest)
 143         {
 144                 case CDC_REQ_GetLineEncoding:
 145                         if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
 146                         {
 147                                 Endpoint_ClearSETUP();
 148
 149                                 /* Write the line coding data to the control endpoint */
 150                                 Endpoint_Write_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t));
 151                                 Endpoint_ClearOUT();
 152                         }
 153
 154                         break;
 155                 case CDC_REQ_SetLineEncoding:
 156                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 157                         {
 158                                 Endpoint_ClearSETUP();
 159
 160                                 /* Read the line coding data in from the host into the global struct */
 161                                 Endpoint_Read_Control_Stream_LE(&LineEncoding, sizeof(CDC_LineEncoding_t));
 162                                 Endpoint_ClearIN();
 163                         }
 164
 165                         break;
 166                 case CDC_REQ_SetControlLineState:
 167                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 168                         {
 169                                 Endpoint_ClearSETUP();
 170                                 Endpoint_ClearStatusStage();
 171
 172                                 /* NOTE: Here you can read in the line state mask from the host, to get the current state of the output handshake
 173                                          lines. The mask is read in from the wValue parameter in USB_ControlRequest, and can be masked against the
 174                                                  CONTROL_LINE_OUT_* masks to determine the RTS and DTR line states using the following code:
 175                                 */
 176                         }
 177
 178                         break;
 179         }
 180 }
 181
 182 /** Function to manage CDC data transmission and reception to and from the host. */
 183 void CDC_Task(void)
 184 {
 185         char*       ReportString    = NULL;
 186         uint8_t     JoyStatus_LCL   = Joystick_GetStatus();
 187         static bool ActionSent      = false;
 188
 189         /* Device must be connected and configured for the task to run */
 190         if (USB_DeviceState != DEVICE_STATE_Configured)
 191           return;
 192
 193         /* Determine if a joystick action has occurred */
 194         if (JoyStatus_LCL & JOY_UP)
 195           ReportString = "Joystick Up\r\n";
 196         else if (JoyStatus_LCL & JOY_DOWN)
 197           ReportString = "Joystick Down\r\n";
 198         else if (JoyStatus_LCL & JOY_LEFT)
 199           ReportString = "Joystick Left\r\n";
 200         else if (JoyStatus_LCL & JOY_RIGHT)
 201           ReportString = "Joystick Right\r\n";
 202         else if (JoyStatus_LCL & JOY_PRESS)
 203           ReportString = "Joystick Pressed\r\n";
 204         else
 205           ActionSent = false;
 206
 207         /* Flag management - Only allow one string to be sent per action */
 208         if ((ReportString != NULL) && (ActionSent == false) && LineEncoding.BaudRateBPS)
 209         {
 210                 ActionSent = true;
 211
 212                 /* Select the Serial Tx Endpoint */
 213                 Endpoint_SelectEndpoint(CDC_TX_EPADDR);
 214
 215                 /* Write the String to the Endpoint */
 216                 Endpoint_Write_Stream_LE(ReportString, strlen(ReportString), NULL);
 217
 218                 /* Remember if the packet to send completely fills the endpoint */
 219                 bool IsFull = (Endpoint_BytesInEndpoint() == CDC_TXRX_EPSIZE);
 220
 221                 /* Finalize the stream transfer to send the last packet */
 222                 Endpoint_ClearIN();
 223
 224                 /* If the last packet filled the endpoint, send an empty packet to release the buffer on
 225                  * the receiver (otherwise all data will be cached until a non-full packet is received) */
 226                 if (IsFull)
 227                 {
 228                         /* Wait until the endpoint is ready for another packet */
 229                         Endpoint_WaitUntilReady();
 230
 231                         /* Send an empty packet to ensure that the host does not buffer data sent to it */
 232                         Endpoint_ClearIN();
 233                 }
 234         }
 235
 236         /* Select the Serial Rx Endpoint */
 237         Endpoint_SelectEndpoint(CDC_RX_EPADDR);
 238
 239         /* Throw away any received data from the host */
 240         if (Endpoint_IsOUTReceived())
 241           Endpoint_ClearOUT();
 242 }
 243