Projects/USBtoSerial/USBtoSerial.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  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 USBtoSerial project. This file contains the main tasks of
  34  *  the demo and is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "USBtoSerial.h"
  38
  39 /** Circular buffer to hold data from the host before it is sent to the device via the serial port. */
  40 RingBuff_t USBtoUSART_Buffer;
  41
  42 /** Circular buffer to hold data from the serial port before it is sent to the host. */
  43 RingBuff_t USARTtoUSB_Buffer;
  44
  45 /** LUFA CDC Class driver interface configuration and state information. This structure is
  46  *  passed to all CDC Class driver functions, so that multiple instances of the same class
  47  *  within a device can be differentiated from one another.
  48  */
  49 USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface =
  50         {
  51                 .Config =
  52                         {
  53                                 .ControlInterfaceNumber         = 0,
  54
  55                                 .DataINEndpointNumber           = CDC_TX_EPNUM,
  56                                 .DataINEndpointSize             = CDC_TXRX_EPSIZE,
  57                                 .DataINEndpointDoubleBank       = false,
  58
  59                                 .DataOUTEndpointNumber          = CDC_RX_EPNUM,
  60                                 .DataOUTEndpointSize            = CDC_TXRX_EPSIZE,
  61                                 .DataOUTEndpointDoubleBank      = false,
  62
  63                                 .NotificationEndpointNumber     = CDC_NOTIFICATION_EPNUM,
  64                                 .NotificationEndpointSize       = CDC_NOTIFICATION_EPSIZE,
  65                                 .NotificationEndpointDoubleBank = false,
  66                         },
  67         };
  68
  69 /** Main program entry point. This routine contains the overall program flow, including initial
  70  *  setup of all components and the main program loop.
  71  */
  72 int main(void)
  73 {
  74         SetupHardware();
  75
  76         Buffer_Initialize(&USBtoUSART_Buffer);
  77         Buffer_Initialize(&USARTtoUSB_Buffer);
  78
  79         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  80
  81         for (;;)
  82         {
  83                 /* Read bytes from the USB OUT endpoint into the USART transmit buffer */
  84                 for (uint8_t DataBytesRem = CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface); DataBytesRem != 0; DataBytesRem--)
  85                 {
  86                         if (!(BUFF_STATICSIZE - USBtoUSART_Buffer.Elements))
  87                           break;
  88
  89                         Buffer_StoreElement(&USBtoUSART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));
  90                 }
  91
  92                 /* Read bytes from the USART receive buffer into the USB IN endpoint */
  93                 if (USARTtoUSB_Buffer.Elements)
  94                   CDC_Device_SendByte(&VirtualSerial_CDC_Interface, Buffer_GetElement(&USARTtoUSB_Buffer));
  95
  96                 /* Load bytes from the USART transmit buffer into the USART */
  97                 if (USBtoUSART_Buffer.Elements)
  98                   Serial_TxByte(Buffer_GetElement(&USBtoUSART_Buffer));
  99
 100                 CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
 101                 USB_USBTask();
 102         }
 103 }
 104
 105 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 106 void SetupHardware(void)
 107 {
 108         /* Disable watchdog if enabled by bootloader/fuses */
 109         MCUSR &= ~(1 << WDRF);
 110         wdt_disable();
 111
 112         /* Disable clock division */
 113         clock_prescale_set(clock_div_1);
 114
 115         /* Hardware Initialization */
 116         Serial_Init(9600, false);
 117         LEDs_Init();
 118         USB_Init();
 119 }
 120
 121 /** Event handler for the library USB Connection event. */
 122 void EVENT_USB_Device_Connect(void)
 123 {
 124         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 125 }
 126
 127 /** Event handler for the library USB Disconnection event. */
 128 void EVENT_USB_Device_Disconnect(void)
 129 {
 130         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 131 }
 132
 133 /** Event handler for the library USB Configuration Changed event. */
 134 void EVENT_USB_Device_ConfigurationChanged(void)
 135 {
 136         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 137
 138         if (!(CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface)))
 139           LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 140 }
 141
 142 /** Event handler for the library USB Unhandled Control Request event. */
 143 void EVENT_USB_Device_UnhandledControlRequest(void)
 144 {
 145         CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
 146 }
 147
 148 /** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer
 149  *  for later transmission to the host.
 150  */
 151 ISR(USART1_RX_vect, ISR_BLOCK)
 152 {
 153         uint8_t ReceivedByte = UDR1;
 154
 155         if (USB_DeviceState == DEVICE_STATE_Configured)
 156           Buffer_StoreElement(&USARTtoUSB_Buffer, ReceivedByte);
 157 }
 158
 159 /** Event handler for the CDC Class driver Line Encoding Changed event.
 160  *
 161  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 162  */
 163 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 164 {
 165         uint8_t ConfigMask = 0;
 166
 167         switch (CDCInterfaceInfo->State.LineEncoding.ParityType)
 168         {
 169                 case CDC_PARITY_Odd:
 170                         ConfigMask = ((1 << UPM11) | (1 << UPM10));
 171                         break;
 172                 case CDC_PARITY_Even:
 173                         ConfigMask = (1 << UPM11);
 174                         break;
 175         }
 176
 177         if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)
 178           ConfigMask |= (1 << USBS1);
 179
 180         switch (CDCInterfaceInfo->State.LineEncoding.DataBits)
 181         {
 182                 case 6:
 183                         ConfigMask |= (1 << UCSZ10);
 184                         break;
 185                 case 7:
 186                         ConfigMask |= (1 << UCSZ11);
 187                         break;
 188                 case 8:
 189                         ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));
 190                         break;
 191         }
 192
 193         UCSR1A = (1 << U2X1);
 194         UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
 195         UCSR1C = ConfigMask;
 196         UBRR1  = SERIAL_2X_UBBRVAL((uint16_t)CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
 197 }