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         sei();
  81
  82         for (;;)
  83         {
  84                 /* Read bytes from the USB OUT endpoint into the USART transmit buffer */
  85                 for (uint8_t DataBytesRem = CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface); DataBytesRem != 0; DataBytesRem--)
  86                 {
  87                         if (!(BUFF_STATICSIZE - USBtoUSART_Buffer.Elements))
  88                           break;
  89
  90                         Buffer_StoreElement(&USBtoUSART_Buffer, CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));
  91                 }
  92
  93                 /* Read bytes from the USART receive buffer into the USB IN endpoint */
  94                 while (USARTtoUSB_Buffer.Elements)
  95                   CDC_Device_SendByte(&VirtualSerial_CDC_Interface, Buffer_GetElement(&USARTtoUSB_Buffer));
  96
  97                 /* Load bytes from the USART transmit buffer into the USART */
  98                 while (USBtoUSART_Buffer.Elements)
  99                   Serial_TxByte(Buffer_GetElement(&USBtoUSART_Buffer));
 100
 101                 CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
 102                 USB_USBTask();
 103         }
 104 }
 105
 106 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 107 void SetupHardware(void)
 108 {
 109         /* Disable watchdog if enabled by bootloader/fuses */
 110         MCUSR &= ~(1 << WDRF);
 111         wdt_disable();
 112
 113         /* Disable clock division */
 114         clock_prescale_set(clock_div_1);
 115
 116         /* Hardware Initialization */
 117         Serial_Init(9600, false);
 118         LEDs_Init();
 119         USB_Init();
 120 }
 121
 122 /** Event handler for the library USB Connection event. */
 123 void EVENT_USB_Device_Connect(void)
 124 {
 125         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 126 }
 127
 128 /** Event handler for the library USB Disconnection event. */
 129 void EVENT_USB_Device_Disconnect(void)
 130 {
 131         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 132 }
 133
 134 /** Event handler for the library USB Configuration Changed event. */
 135 void EVENT_USB_Device_ConfigurationChanged(void)
 136 {
 137         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 138
 139         if (!(CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface)))
 140           LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 141 }
 142
 143 /** Event handler for the library USB Unhandled Control Request event. */
 144 void EVENT_USB_Device_UnhandledControlRequest(void)
 145 {
 146         CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
 147 }
 148
 149 /** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer
 150  *  for later transmission to the host.
 151  */
 152 ISR(USART1_RX_vect, ISR_BLOCK)
 153 {
 154         uint8_t ReceivedByte = UDR1;
 155
 156         if (USB_DeviceState == DEVICE_STATE_Configured)
 157           Buffer_StoreElement(&USARTtoUSB_Buffer, ReceivedByte);
 158 }
 159
 160 /** Event handler for the CDC Class driver Line Encoding Changed event.
 161  *
 162  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 163  */
 164 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 165 {
 166         uint8_t ConfigMask = 0;
 167
 168         switch (CDCInterfaceInfo->State.LineEncoding.ParityType)
 169         {
 170                 case CDC_PARITY_Odd:
 171                         ConfigMask = ((1 << UPM11) | (1 << UPM10));
 172                         break;
 173                 case CDC_PARITY_Even:
 174                         ConfigMask = (1 << UPM11);
 175                         break;
 176         }
 177
 178         if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)
 179           ConfigMask |= (1 << USBS1);
 180
 181         switch (CDCInterfaceInfo->State.LineEncoding.DataBits)
 182         {
 183                 case 6:
 184                         ConfigMask |= (1 << UCSZ10);
 185                         break;
 186                 case 7:
 187                         ConfigMask |= (1 << UCSZ11);
 188                         break;
 189                 case 8:
 190                         ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));
 191                         break;
 192         }
 193
 194         UCSR1A = (1 << U2X1);
 195         UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
 196         UCSR1C = ConfigMask;
 197         UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
 198 }