Projects/Benito/Benito.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2012.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2012  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 Benito project. This file contains the main tasks of
  34  *  the project and is responsible for the initial application hardware configuration.
  35  */
  36
  37 #include "Benito.h"
  38
  39 /** Circular buffer to hold data from the serial port before it is sent to the host. */
  40 static RingBuffer_t USARTtoUSB_Buffer;
  41
  42 /** Underlying data buffer for \ref USARTtoUSB_Buffer, where the stored bytes are located. */
  43 static uint8_t      USARTtoUSB_Buffer_Data[128];
  44
  45 /** Pulse generation counters to keep track of the number of milliseconds remaining for each pulse type */
  46 volatile struct
  47 {
  48         uint8_t ResetPulse; /**< Milliseconds remaining for target /RESET pulse */
  49         uint8_t TxLEDPulse; /**< Milliseconds remaining for data Tx LED pulse */
  50         uint8_t RxLEDPulse; /**< Milliseconds remaining for data Rx LED pulse */
  51         uint8_t PingPongLEDPulse; /**< Milliseconds remaining for enumeration Tx/Rx ping-pong LED pulse */
  52 } PulseMSRemaining;
  53
  54 /** Milliseconds remaining until the receive buffer is flushed to the USB host */
  55 uint8_t FlushPeriodRemaining = RECEIVE_BUFFER_FLUSH_MS;
  56
  57 /** LUFA CDC Class driver interface configuration and state information. This structure is
  58  *  passed to all CDC Class driver functions, so that multiple instances of the same class
  59  *  within a device can be differentiated from one another.
  60  */
  61 USB_ClassInfo_CDC_Device_t VirtualSerial_CDC_Interface =
  62         {
  63                 .Config =
  64                         {
  65                                 .ControlInterfaceNumber   = 0,
  66                                 .DataINEndpoint           =
  67                                         {
  68                                                 .Address          = CDC_TX_EPADDR,
  69                                                 .Size             = CDC_TXRX_EPSIZE,
  70                                                 .Banks            = 1,
  71                                         },
  72                                 .DataOUTEndpoint =
  73                                         {
  74                                                 .Address          = CDC_RX_EPADDR,
  75                                                 .Size             = CDC_TXRX_EPSIZE,
  76                                                 .Banks            = 1,
  77                                         },
  78                                 .NotificationEndpoint =
  79                                         {
  80                                                 .Address          = CDC_NOTIFICATION_EPADDR,
  81                                                 .Size             = CDC_NOTIFICATION_EPSIZE,
  82                                                 .Banks            = 1,
  83                                         },
  84                         },
  85         };
  86
  87 /** Main program entry point. This routine contains the overall program flow, including initial
  88  *  setup of all components and the main program loop.
  89  */
  90 int main(void)
  91 {
  92         SetupHardware();
  93
  94         RingBuffer_InitBuffer(&USARTtoUSB_Buffer, USARTtoUSB_Buffer_Data, sizeof(USARTtoUSB_Buffer_Data));
  95
  96         sei();
  97
  98         for (;;)
  99         {
 100                 /* Echo bytes from the host to the target via the hardware USART */
 101                 if ((UCSR1A & (1 << UDRE1)) && CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface))
 102                 {
 103                         UDR1 = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
 104
 105                         LEDs_TurnOnLEDs(LEDMASK_TX);
 106                         PulseMSRemaining.TxLEDPulse = TX_RX_LED_PULSE_MS;
 107                 }
 108
 109                 /* Check if the millisecond timer has elapsed */
 110                 if (TIFR0 & (1 << OCF0A))
 111                 {
 112                         /* Clear flush timer expiry flag */
 113                         TIFR0 |= (1 << TOV0);
 114
 115                         /* Check if the reset pulse period has elapsed, if so tristate the target reset line */
 116                         if (PulseMSRemaining.ResetPulse && !(--PulseMSRemaining.ResetPulse))
 117                         {
 118                                 LEDs_TurnOffLEDs(LEDMASK_BUSY);
 119                                 AVR_RESET_LINE_DDR &= ~AVR_RESET_LINE_MASK;
 120                         }
 121
 122                         /* Check if the LEDs should be ping-ponging (during enumeration) */
 123                         if (PulseMSRemaining.PingPongLEDPulse && !(--PulseMSRemaining.PingPongLEDPulse))
 124                         {
 125                                 LEDs_ToggleLEDs(LEDMASK_TX | LEDMASK_RX);
 126                                 PulseMSRemaining.PingPongLEDPulse = PING_PONG_LED_PULSE_MS;
 127                         }
 128
 129                         /* Turn off TX LED(s) once the TX pulse period has elapsed */
 130                         if (PulseMSRemaining.TxLEDPulse && !(--PulseMSRemaining.TxLEDPulse))
 131                           LEDs_TurnOffLEDs(LEDMASK_TX);
 132
 133                         /* Turn off RX LED(s) once the RX pulse period has elapsed */
 134                         if (PulseMSRemaining.RxLEDPulse && !(--PulseMSRemaining.RxLEDPulse))
 135                           LEDs_TurnOffLEDs(LEDMASK_RX);
 136
 137                         /* Check if the receive buffer flush period has expired */
 138                         uint16_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer);
 139                         if (!(--FlushPeriodRemaining) || (BufferCount > 200))
 140                         {
 141                                 FlushPeriodRemaining = RECEIVE_BUFFER_FLUSH_MS;
 142
 143                                 /* Start RX LED indicator pulse */
 144                                 if (BufferCount)
 145                                 {
 146                                         LEDs_TurnOnLEDs(LEDMASK_RX);
 147                                         PulseMSRemaining.RxLEDPulse = TX_RX_LED_PULSE_MS;
 148                                 }
 149
 150                                 /* Echo bytes from the target to the host via the virtual serial port */
 151                                 while (BufferCount--)
 152                                 {
 153                                         /* Try to send the next byte of data to the host, abort if there is an error without dequeuing */
 154                                         if (CDC_Device_SendByte(&VirtualSerial_CDC_Interface,
 155                                                                                         RingBuffer_Peek(&USARTtoUSB_Buffer)) != ENDPOINT_READYWAIT_NoError)
 156                                         {
 157                                                 break;
 158                                         }
 159
 160                                         /* Dequeue the already sent byte from the buffer now we have confirmed that no transmission error occurred */
 161                                         RingBuffer_Remove(&USARTtoUSB_Buffer);
 162                                 }
 163                         }
 164                 }
 165
 166                 CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
 167                 USB_USBTask();
 168         }
 169 }
 170
 171 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 172 void SetupHardware(void)
 173 {
 174         /* Disable watchdog if enabled by bootloader/fuses */
 175         MCUSR &= ~(1 << WDRF);
 176         wdt_disable();
 177
 178         /* Hardware Initialization */
 179         LEDs_Init();
 180         USB_Init();
 181
 182         /* Millisecond Timer Interrupt */
 183         OCR0A  = (F_CPU / 64 / 1000);
 184         TCCR0A = (1 << WGM01);
 185         TCCR0B = ((1 << CS01) | (1 << CS00));
 186
 187         /* Tristate target /RESET Line */
 188         AVR_RESET_LINE_PORT &= ~AVR_RESET_LINE_MASK;
 189         AVR_RESET_LINE_DDR  &= ~AVR_RESET_LINE_MASK;
 190 }
 191
 192 /** Event handler for the library USB Connection event. */
 193 void EVENT_USB_Device_Connect(void)
 194 {
 195         PulseMSRemaining.PingPongLEDPulse = PING_PONG_LED_PULSE_MS;
 196         LEDs_SetAllLEDs(LEDMASK_TX);
 197 }
 198
 199 /** Event handler for the library USB Disconnection event. */
 200 void EVENT_USB_Device_Disconnect(void)
 201 {
 202         PulseMSRemaining.PingPongLEDPulse = 0;
 203         LEDs_SetAllLEDs(LEDS_NO_LEDS);
 204 }
 205
 206 /** Event handler for the library USB Configuration Changed event. */
 207 void EVENT_USB_Device_ConfigurationChanged(void)
 208 {
 209         bool ConfigSuccess = true;
 210
 211         ConfigSuccess &= CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface);
 212
 213         PulseMSRemaining.PingPongLEDPulse = 0;
 214
 215         LEDs_SetAllLEDs(ConfigSuccess ? LEDS_NO_LEDS : LEDMASK_ERROR);
 216 }
 217
 218 /** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to
 219  *  the device from the USB host before passing along unhandled control requests to the library for processing
 220  *  internally.
 221  */
 222 void EVENT_USB_Device_ControlRequest(void)
 223 {
 224         CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
 225 }
 226
 227 /** Event handler for the CDC Class driver Line Encoding Changed event.
 228  *
 229  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 230  */
 231 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 232 {
 233         uint8_t ConfigMask = 0;
 234
 235         switch (CDCInterfaceInfo->State.LineEncoding.ParityType)
 236         {
 237                 case CDC_PARITY_Odd:
 238                         ConfigMask = ((1 << UPM11) | (1 << UPM10));
 239                         break;
 240                 case CDC_PARITY_Even:
 241                         ConfigMask = (1 << UPM11);
 242                         break;
 243         }
 244
 245         if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)
 246           ConfigMask |= (1 << USBS1);
 247
 248         switch (CDCInterfaceInfo->State.LineEncoding.DataBits)
 249         {
 250                 case 6:
 251                         ConfigMask |= (1 << UCSZ10);
 252                         break;
 253                 case 7:
 254                         ConfigMask |= (1 << UCSZ11);
 255                         break;
 256                 case 8:
 257                         ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));
 258                         break;
 259         }
 260
 261         /* Must turn off USART before reconfiguring it, otherwise incorrect operation may occur */
 262         UCSR1B = 0;
 263         UCSR1A = 0;
 264         UCSR1C = 0;
 265
 266         /* Set the new baud rate before configuring the USART */
 267         UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
 268
 269         /* Reconfigure the USART in double speed mode for a wider baud rate range at the expense of accuracy */
 270         UCSR1C = ConfigMask;
 271         UCSR1A = (1 << U2X1);
 272         UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
 273 }
 274
 275 /** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer
 276  *  for later transmission to the host.
 277  */
 278 ISR(USART1_RX_vect, ISR_BLOCK)
 279 {
 280         uint8_t ReceivedByte = UDR1;
 281
 282         if (USB_DeviceState == DEVICE_STATE_Configured)
 283           RingBuffer_Insert(&USARTtoUSB_Buffer, ReceivedByte);
 284 }
 285
 286 /** Event handler for the CDC Class driver Host-to-Device Line Encoding Changed event.
 287  *
 288  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 289  */
 290 void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 291 {
 292         static bool PreviousDTRState = false;
 293         bool        CurrentDTRState  = (CDCInterfaceInfo->State.ControlLineStates.HostToDevice & CDC_CONTROL_LINE_OUT_DTR);
 294
 295         /* Check if the DTR line has been asserted - if so, start the target AVR's reset pulse */
 296         if (!(PreviousDTRState) && CurrentDTRState)
 297         {
 298                 LEDs_SetAllLEDs(LEDMASK_BUSY);
 299
 300                 AVR_RESET_LINE_DDR |= AVR_RESET_LINE_MASK;
 301                 PulseMSRemaining.ResetPulse = AVR_RESET_PULSE_MS;
 302         }
 303
 304         PreviousDTRState = CurrentDTRState;
 305 }
 306