3      Copyright (C) Dean Camera, 2018. 
   5   dean [at] fourwalledcubicle [dot] com 
  10   Copyright 2018  Dean Camera (dean [at] fourwalledcubicle [dot] com) 
  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. 
  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 
  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. 
  37 #include "XPLAINBridge.h" 
  39 /** Current firmware mode, making the device behave as either a programmer or a USART bridge */ 
  40 bool CurrentFirmwareMode 
= MODE_USART_BRIDGE
; 
  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. 
  46 USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface 
= 
  50                                 .ControlInterfaceNumber         
= INTERFACE_ID_CDC_CCI
, 
  53                                                 .Address                
= CDC_TX_EPADDR
, 
  54                                                 .Size                   
= CDC_TXRX_EPSIZE
, 
  59                                                 .Address                
= CDC_RX_EPADDR
, 
  60                                                 .Size                   
= CDC_TXRX_EPSIZE
, 
  63                                 .NotificationEndpoint           
= 
  65                                                 .Address                
= CDC_NOTIFICATION_EPADDR
, 
  66                                                 .Size                   
= CDC_NOTIFICATION_EPSIZE
, 
  72 /** Circular buffer to hold data from the host before it is sent to the device via the serial port. */ 
  73 RingBuffer_t   USBtoUART_Buffer
; 
  75 /** Underlying data buffer for \ref USBtoUART_Buffer, where the stored bytes are located. */ 
  76 static uint8_t USBtoUART_Buffer_Data
[128]; 
  78 /** Circular buffer to hold data from the serial port before it is sent to the host. */ 
  79 RingBuffer_t   UARTtoUSB_Buffer
; 
  81 /** Underlying data buffer for \ref UARTtoUSB_Buffer, where the stored bytes are located. */ 
  82 static uint8_t UARTtoUSB_Buffer_Data
[128]; 
  85 /** Main program entry point. This routine contains the overall program flow, including initial 
  86  *  setup of all components and the main program loop. 
  92         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY
); 
  93         GlobalInterruptEnable(); 
  97                 if (CurrentFirmwareMode 
== MODE_USART_BRIDGE
) 
 106 void AVRISP_Task(void) 
 108         /* Must be in the configured state for the AVRISP code to process data */ 
 109         if (USB_DeviceState 
!= DEVICE_STATE_Configured
) 
 112         V2Params_UpdateParamValues(); 
 114         Endpoint_SelectEndpoint(AVRISP_DATA_OUT_EPADDR
); 
 116         /* Check to see if a V2 Protocol command has been received */ 
 117         if (Endpoint_IsOUTReceived()) 
 119                 LEDs_SetAllLEDs(LEDMASK_BUSY
); 
 121                 /* Pass off processing of the V2 Protocol command to the V2 Protocol handler */ 
 122                 V2Protocol_ProcessCommand(); 
 124                 LEDs_SetAllLEDs(LEDMASK_USB_READY
); 
 128 void UARTBridge_Task(void) 
 130         /* Must be in the configured state for the USART Bridge code to process data */ 
 131         if (USB_DeviceState 
!= DEVICE_STATE_Configured
) 
 134         /* Only try to read in bytes from the CDC interface if the transmit buffer is not full */ 
 135         if (!(RingBuffer_IsFull(&USBtoUART_Buffer
))) 
 137                 int16_t ReceivedByte 
= CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface
); 
 139                 /* Read bytes from the USB OUT endpoint into the UART transmit buffer */ 
 140                 if (!(ReceivedByte 
< 0)) 
 141                   RingBuffer_Insert(&USBtoUART_Buffer
, ReceivedByte
); 
 144         /* Check if the UART receive buffer flush timer has expired or buffer is nearly full */ 
 145         uint16_t BufferCount 
= RingBuffer_GetCount(&UARTtoUSB_Buffer
); 
 146         if ((TIFR0 
& (1 << TOV0
)) || (BufferCount 
> 200)) 
 148                 /* Clear flush timer expiry flag */ 
 149                 TIFR0 
|= (1 << TOV0
); 
 151                 /* Read bytes from the USART receive buffer into the USB IN endpoint */ 
 152                 while (BufferCount
--) 
 154                         /* Try to send the next byte of data to the host, abort if there is an error without dequeuing */ 
 155                         if (CDC_Device_SendByte(&VirtualSerial_CDC_Interface
, 
 156                                                                         RingBuffer_Peek(&UARTtoUSB_Buffer
)) != ENDPOINT_READYWAIT_NoError
) 
 161                         /* Dequeue the already sent byte from the buffer now we have confirmed that no transmission error occurred */ 
 162                         RingBuffer_Remove(&UARTtoUSB_Buffer
); 
 166         CDC_Device_USBTask(&VirtualSerial_CDC_Interface
); 
 169 /** Configures the board hardware and chip peripherals for the demo's functionality. */ 
 170 void SetupHardware(void) 
 172 #if (ARCH == ARCH_AVR8) 
 173         /* Disable watchdog if enabled by bootloader/fuses */ 
 174         MCUSR 
&= ~(1 << WDRF
); 
 177         /* Disable clock division */ 
 178         clock_prescale_set(clock_div_1
); 
 181         /* Disable JTAG debugging */ 
 185         /* Enable pull-up on the JTAG TDI pin so we can use it to select the mode */ 
 189         /* Select the firmware mode based on the JTD pin's value */ 
 190         CurrentFirmwareMode 
= (PINF 
& (1 << 7)) ? MODE_USART_BRIDGE 
: MODE_PDI_PROGRAMMER
; 
 192         /* Re-enable JTAG debugging */ 
 193         MCUCR 
&= ~(1 << JTD
); 
 194         MCUCR 
&= ~(1 << JTD
); 
 196         /* Hardware Initialization */ 
 199         #if defined(RESET_TOGGLES_LIBUSB_COMPAT) 
 200         UpdateCurrentCompatibilityMode(); 
 203         /* USB Stack Initialization */ 
 207 /** Event handler for the library USB Configuration Changed event. */ 
 208 void EVENT_USB_Device_ConfigurationChanged(void) 
 210         bool ConfigSuccess 
= true; 
 212         /* Configure the device endpoints according to the selected mode */ 
 213         if (CurrentFirmwareMode 
== MODE_USART_BRIDGE
) 
 215                 ConfigSuccess 
&= CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface
); 
 217                 /* Configure the UART flush timer - run at Fcpu/1024 for maximum interval before overflow */ 
 218                 TCCR0B 
= ((1 << CS02
) | (1 << CS00
)); 
 220                 /* Initialize ring buffers used to hold serial data between USB and software UART interfaces */ 
 221                 RingBuffer_InitBuffer(&USBtoUART_Buffer
, USBtoUART_Buffer_Data
, sizeof(USBtoUART_Buffer_Data
)); 
 222                 RingBuffer_InitBuffer(&UARTtoUSB_Buffer
, UARTtoUSB_Buffer_Data
, sizeof(UARTtoUSB_Buffer_Data
)); 
 224                 /* Start the software USART */ 
 229                 ConfigSuccess 
&= Endpoint_ConfigureEndpoint(AVRISP_DATA_OUT_EPADDR
, EP_TYPE_BULK
, AVRISP_DATA_EPSIZE
, 1); 
 231                 if ((AVRISP_DATA_IN_EPADDR 
& ENDPOINT_EPNUM_MASK
) != (AVRISP_DATA_OUT_EPADDR 
& ENDPOINT_EPNUM_MASK
)) 
 232                   ConfigSuccess 
&= Endpoint_ConfigureEndpoint(AVRISP_DATA_IN_EPADDR
, EP_TYPE_BULK
, AVRISP_DATA_EPSIZE
, 1); 
 234                 /* Configure the V2 protocol packet handler */ 
 238         LEDs_SetAllLEDs(ConfigSuccess ? LEDMASK_USB_READY 
: LEDMASK_USB_ERROR
); 
 241 /** Event handler for the library USB Control Request reception event. */ 
 242 void EVENT_USB_Device_ControlRequest(void) 
 244         if (CurrentFirmwareMode 
== MODE_USART_BRIDGE
) 
 245           CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface
); 
 248 /** Event handler for the library USB Connection event. */ 
 249 void EVENT_USB_Device_Connect(void) 
 251         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING
); 
 254 /** Event handler for the library USB Disconnection event. */ 
 255 void EVENT_USB_Device_Disconnect(void) 
 257         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY
); 
 260 /** Event handler for the CDC Class driver Line Encoding Changed event. 
 262  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced 
 264 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t
* const CDCInterfaceInfo
) 
 266         /* Change the software UART's baud rate to match the new baud rate */ 
 267         SoftUART_SetBaud(CDCInterfaceInfo
->State
.LineEncoding
.BaudRateBPS
); 
 270 /** This function is called by the library when in device mode, and must be overridden (see library "USB Descriptors" 
 271  *  documentation) by the application code so that the address and size of a requested descriptor can be given 
 272  *  to the USB library. When the device receives a Get Descriptor request on the control endpoint, this function 
 273  *  is called so that the descriptor details can be passed back and the appropriate descriptor sent back to the 
 276  *  \param[in]  wValue                 Descriptor type and index to retrieve 
 277  *  \param[in]  wIndex                 Sub-index to retrieve (such as a localized string language) 
 278  *  \param[out] DescriptorAddress      Address of the retrieved descriptor 
 280  *  \return Length of the retrieved descriptor in bytes, or NO_DESCRIPTOR if the descriptor was not found 
 282 uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue
, 
 283                                     const uint16_t wIndex
, 
 284                                     const void** const DescriptorAddress
) 
 286         /* Return the correct descriptors based on the selected mode */ 
 287         if (CurrentFirmwareMode 
== MODE_USART_BRIDGE
) 
 288           return USART_GetDescriptor(wValue
, wIndex
, DescriptorAddress
); 
 290           return AVRISP_GetDescriptor(wValue
, wIndex
, DescriptorAddress
);