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