Projects/XPLAINBridge/XPLAINBridge.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 XPLAINBridge project. This file contains the main tasks of
  34  *  the project and is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "XPLAINBridge.h"
  38
  39 /** Current firmware mode, making the device behave as either a programmer or a USART bridge */
  40 bool CurrentFirmwareMode = MODE_USART_BRIDGE;
  41
  42 /** LUFA CDC Class driver interface configuration and state information. This structure is
  43  *  passed to all CDC Class driver functions, so that multiple instances of the same class
  44  *  within a device can be differentiated from one another.
  45  */
  46 USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface =
  47         {
  48                 .Config =
  49                         {
  50                                 .ControlInterfaceNumber         = 0,
  51
  52                                 .DataINEndpointNumber           = CDC_TX_EPNUM,
  53                                 .DataINEndpointSize             = CDC_TXRX_EPSIZE,
  54                                 .DataINEndpointDoubleBank       = true,
  55
  56                                 .DataOUTEndpointNumber          = CDC_RX_EPNUM,
  57                                 .DataOUTEndpointSize            = CDC_TXRX_EPSIZE,
  58                                 .DataOUTEndpointDoubleBank      = true,
  59
  60                                 .NotificationEndpointNumber     = CDC_NOTIFICATION_EPNUM,
  61                                 .NotificationEndpointSize       = CDC_NOTIFICATION_EPSIZE,
  62                                 .NotificationEndpointDoubleBank = false,
  63                         },
  64         };
  65
  66 /** Circular buffer to hold data from the host before it is sent to the device via the serial port. */
  67 RingBuffer_t   USBtoUART_Buffer;
  68
  69 /** Underlying data buffer for \ref USBtoUART_Buffer, where the stored bytes are located. */
  70 static uint8_t USBtoUART_Buffer_Data[128];
  71
  72 /** Circular buffer to hold data from the serial port before it is sent to the host. */
  73 RingBuffer_t   UARTtoUSB_Buffer;
  74
  75 /** Underlying data buffer for \ref UARTtoUSB_Buffer, where the stored bytes are located. */
  76 static uint8_t UARTtoUSB_Buffer_Data[128];
  77
  78
  79 /** Main program entry point. This routine contains the overall program flow, including initial
  80  *  setup of all components and the main program loop.
  81  */
  82 int main(void)
  83 {
  84         SetupHardware();
  85
  86         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  87         sei();
  88
  89         for (;;)
  90         {
  91                 if (CurrentFirmwareMode == MODE_USART_BRIDGE)
  92                   UARTBridge_Task();
  93                 else
  94                   AVRISP_Task();
  95
  96                 USB_USBTask();
  97         }
  98 }
  99
 100 void AVRISP_Task(void)
 101 {
 102         /* Must be in the configured state for the AVRISP code to process data */
 103         if (USB_DeviceState != DEVICE_STATE_Configured)
 104           return;
 105
 106         V2Params_UpdateParamValues();
 107
 108         Endpoint_SelectEndpoint(AVRISP_DATA_OUT_EPNUM);
 109
 110         /* Check to see if a V2 Protocol command has been received */
 111         if (Endpoint_IsOUTReceived())
 112         {
 113                 LEDs_SetAllLEDs(LEDMASK_BUSY);
 114
 115                 /* Pass off processing of the V2 Protocol command to the V2 Protocol handler */
 116                 V2Protocol_ProcessCommand();
 117
 118                 LEDs_SetAllLEDs(LEDMASK_USB_READY);
 119         }
 120 }
 121
 122 void UARTBridge_Task(void)
 123 {
 124         /* Must be in the configured state for the USART Bridge code to process data */
 125         if (USB_DeviceState != DEVICE_STATE_Configured)
 126           return;
 127
 128         /* Only try to read in bytes from the CDC interface if the transmit buffer is not full */
 129         if (!(RingBuffer_IsFull(&USBtoUART_Buffer)))
 130         {
 131                 int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
 132
 133                 /* Read bytes from the USB OUT endpoint into the UART transmit buffer */
 134                 if (!(ReceivedByte < 0))
 135                   RingBuffer_Insert(&USBtoUART_Buffer, ReceivedByte);
 136         }
 137
 138         /* Check if the UART receive buffer flush timer has expired or buffer is nearly full */
 139         uint16_t BufferCount = RingBuffer_GetCount(&UARTtoUSB_Buffer);
 140         if ((TIFR0 & (1 << TOV0)) || (BufferCount > 200))
 141         {
 142                 /* Clear flush timer expiry flag */
 143                 TIFR0 |= (1 << TOV0);
 144
 145                 /* Read bytes from the USART receive buffer into the USB IN endpoint */
 146                 while (BufferCount--)
 147                 {
 148                         /* Try to send the next byte of data to the host, abort if there is an error without dequeuing */
 149                         if (CDC_Device_SendByte(&VirtualSerial_CDC_Interface,
 150                                                                         RingBuffer_Peek(&UARTtoUSB_Buffer)) != ENDPOINT_READYWAIT_NoError)
 151                         {
 152                                 break;
 153                         }
 154
 155                         /* Dequeue the already sent byte from the buffer now we have confirmed that no transmission error occurred */
 156                         RingBuffer_Remove(&UARTtoUSB_Buffer);
 157                 }
 158         }
 159
 160         CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
 161 }
 162
 163 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 164 void SetupHardware(void)
 165 {
 166         /* Disable watchdog if enabled by bootloader/fuses */
 167         MCUSR &= ~(1 << WDRF);
 168         wdt_disable();
 169
 170         /* Disable clock division */
 171         clock_prescale_set(clock_div_1);
 172
 173         /* Hardware Initialization */
 174         SoftUART_Init();
 175         LEDs_Init();
 176         USB_Init();
 177
 178         /* Disable JTAG debugging */
 179         MCUCR |= (1 << JTD);
 180         MCUCR |= (1 << JTD);
 181
 182         /* Enable pull-up on the JTAG TDI pin so we can use it to select the mode */
 183         PORTF |= (1 << 7);
 184         Delay_MS(10);
 185
 186         /* Select the firmware mode based on the JTD pin's value */
 187         CurrentFirmwareMode = (PINF & (1 << 7)) ? MODE_USART_BRIDGE : MODE_PDI_PROGRAMMER;
 188
 189         /* Re-enable JTAG debugging */
 190         MCUCR &= ~(1 << JTD);
 191         MCUCR &= ~(1 << JTD);
 192 }
 193
 194 /** Event handler for the library USB Configuration Changed event. */
 195 void EVENT_USB_Device_ConfigurationChanged(void)
 196 {
 197         bool ConfigSuccess = true;
 198
 199         /* Configure the device endpoints according to the selected mode */
 200         if (CurrentFirmwareMode == MODE_USART_BRIDGE)
 201         {
 202                 ConfigSuccess &= CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface);
 203
 204                 /* Configure the UART flush timer - run at Fcpu/1024 for maximum interval before overflow */
 205                 TCCR0B = ((1 << CS02) | (1 << CS00));
 206
 207                 /* Initialize ring buffers used to hold serial data between USB and software UART interfaces */
 208                 RingBuffer_InitBuffer(&USBtoUART_Buffer, USBtoUART_Buffer_Data, sizeof(USBtoUART_Buffer_Data));
 209                 RingBuffer_InitBuffer(&UARTtoUSB_Buffer, UARTtoUSB_Buffer_Data, sizeof(UARTtoUSB_Buffer_Data));
 210
 211                 /* Start the software USART */
 212                 SoftUART_Init();
 213         }
 214         else
 215         {
 216                 ConfigSuccess &= Endpoint_ConfigureEndpoint(AVRISP_DATA_OUT_EPNUM, EP_TYPE_BULK, ENDPOINT_DIR_OUT,
 217                                                             AVRISP_DATA_EPSIZE, ENDPOINT_BANK_SINGLE);
 218
 219                 #if defined(LIBUSB_DRIVER_COMPAT)
 220                 ConfigSuccess &= Endpoint_ConfigureEndpoint(AVRISP_DATA_IN_EPNUM, EP_TYPE_BULK, ENDPOINT_DIR_IN,
 221                                                             AVRISP_DATA_EPSIZE, ENDPOINT_BANK_SINGLE);
 222                 #endif
 223
 224                 /* Configure the V2 protocol packet handler */
 225                 V2Protocol_Init();
 226         }
 227
 228         LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY : LEDMASK_USB_ERROR);
 229 }
 230
 231 /** Event handler for the library USB Control Request reception event. */
 232 void EVENT_USB_Device_ControlRequest(void)
 233 {
 234         if (CurrentFirmwareMode == MODE_USART_BRIDGE)
 235           CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
 236 }
 237
 238 /** Event handler for the library USB Connection event. */
 239 void EVENT_USB_Device_Connect(void)
 240 {
 241         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
 242 }
 243
 244 /** Event handler for the library USB Disconnection event. */
 245 void EVENT_USB_Device_Disconnect(void)
 246 {
 247         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 248 }
 249
 250 /** Event handler for the CDC Class driver Line Encoding Changed event.
 251  *
 252  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 253  */
 254 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 255 {
 256         /* Change the software UART's baud rate to match the new baud rate */
 257         SoftUART_SetBaud(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
 258 }
 259
 260 /** This function is called by the library when in device mode, and must be overridden (see library "USB Descriptors"
 261  *  documentation) by the application code so that the address and size of a requested descriptor can be given
 262  *  to the USB library. When the device receives a Get Descriptor request on the control endpoint, this function
 263  *  is called so that the descriptor details can be passed back and the appropriate descriptor sent back to the
 264  *  USB host.
 265  *
 266  *  \param[in]  wValue  Descriptor type and index to retrieve
 267  *  \param[in]  wIndex  Sub-index to retrieve (such as a localized string language)
 268  *  \param[out] DescriptorAddress  Address of the retrieved descriptor
 269  *
 270  *  \return Length of the retrieved descriptor in bytes, or NO_DESCRIPTOR if the descriptor was not found
 271  */
 272 uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,
 273                                     const uint8_t wIndex,
 274                                     const void** const DescriptorAddress)
 275 {
 276         /* Return the correct descriptors based on the selected mode */
 277         if (CurrentFirmwareMode == MODE_USART_BRIDGE)
 278           return USART_GetDescriptor(wValue, wIndex, DescriptorAddress);
 279         else
 280           return AVRISP_GetDescriptor(wValue, wIndex, DescriptorAddress);
 281 }
 282