Projects/Benito/Benito.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 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 RingBuff_t Tx_Buffer;
  41
  42 /** Pulse generation counters to keep track of the number of milliseconds remaining for each pulse type */
  43 volatile struct
  44 {
  45         uint8_t ResetPulse; /**< Milliseconds remaining for target /RESET pulse */
  46         uint8_t TxLEDPulse; /**< Milliseconds remaining for data Tx LED pulse */
  47         uint8_t RxLEDPulse; /**< Milliseconds remaining for data Rx LED pulse */
  48         uint8_t PingPongLEDPulse; /**< Milliseconds remaining for enumeration Tx/Rx ping-pong LED pulse */
  49 } PulseMSRemaining;
  50
  51 /** Previous state of the virtual DTR control line from the host */
  52 bool PreviousDTRState = false;
  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(&Tx_Buffer);
  89
  90         sei();
  91
  92         for (;;)
  93         {
  94                 /* Echo bytes from the host to the target via the hardware USART */
  95                 int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);
  96                 if (!(ReceivedByte < 0) && (UCSR1A & (1 << UDRE1)))
  97                 {
  98                         UDR1 = ReceivedByte;
  99
 100                         LEDs_TurnOnLEDs(LEDMASK_TX);
 101                         PulseMSRemaining.TxLEDPulse = TX_RX_LED_PULSE_MS;
 102                 }
 103
 104                 /* Check if the millisecond timer has elapsed */
 105                 if (TIFR0 & (1 << OCF0A))
 106                 {
 107                         /* Check if the reset pulse period has elapsed, if so tristate the target reset line */
 108                         if (PulseMSRemaining.ResetPulse && !(--PulseMSRemaining.ResetPulse))
 109                         {
 110                                 LEDs_TurnOffLEDs(LEDMASK_BUSY);
 111                                 AVR_RESET_LINE_DDR &= ~AVR_RESET_LINE_MASK;
 112                         }
 113
 114                         /* Check if the LEDs should be ping-ponging (during enumeration) */
 115                         if (PulseMSRemaining.PingPongLEDPulse && !(--PulseMSRemaining.PingPongLEDPulse))
 116                         {
 117                                 LEDs_ToggleLEDs(LEDMASK_TX | LEDMASK_RX);
 118                                 PulseMSRemaining.PingPongLEDPulse = PING_PONG_LED_PULSE_MS;
 119                         }
 120
 121                         /* Turn off TX LED(s) once the TX pulse period has elapsed */
 122                         if (PulseMSRemaining.TxLEDPulse && !(--PulseMSRemaining.TxLEDPulse))
 123                           LEDs_TurnOffLEDs(LEDMASK_TX);
 124
 125                         /* Turn off RX LED(s) once the RX pulse period has elapsed */
 126                         if (PulseMSRemaining.RxLEDPulse && !(--PulseMSRemaining.RxLEDPulse))
 127                           LEDs_TurnOffLEDs(LEDMASK_RX);
 128
 129                         /* Check if the receive buffer flush period has expired */
 130                         RingBuff_Count_t BufferCount = RingBuffer_GetCount(&Tx_Buffer);
 131                         if (!(--FlushPeriodRemaining) || (BufferCount > 200))
 132                         {
 133                                 /* Echo bytes from the target to the host via the virtual serial port */
 134                                 if (BufferCount)
 135                                 {
 136                                         while (BufferCount--)
 137                                           CDC_Device_SendByte(&VirtualSerial_CDC_Interface, RingBuffer_Remove(&Tx_Buffer));
 138
 139                                         LEDs_TurnOnLEDs(LEDMASK_RX);
 140                                         PulseMSRemaining.RxLEDPulse = TX_RX_LED_PULSE_MS;
 141                                 }
 142
 143                                 FlushPeriodRemaining = RECEIVE_BUFFER_FLUSH_MS;
 144                         }
 145
 146                         /* Clear the millisecond timer CTC flag (cleared by writing logic one to the register) */
 147                         TIFR0 |= (1 << OCF0A);
 148                 }
 149
 150                 CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
 151                 USB_USBTask();
 152         }
 153 }
 154
 155 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 156 void SetupHardware(void)
 157 {
 158         /* Disable watchdog if enabled by bootloader/fuses */
 159         MCUSR &= ~(1 << WDRF);
 160         wdt_disable();
 161
 162         /* Hardware Initialization */
 163         LEDs_Init();
 164         USB_Init();
 165
 166         /* Millisecond Timer Interrupt */
 167         OCR0A  = (F_CPU / 64 / 1000);
 168         TCCR0A = (1 << WGM01);
 169         TCCR0B = ((1 << CS01) | (1 << CS00));
 170
 171         /* Tristate target /RESET Line */
 172         AVR_RESET_LINE_PORT &= ~AVR_RESET_LINE_MASK;
 173         AVR_RESET_LINE_DDR  &= ~AVR_RESET_LINE_MASK;
 174 }
 175
 176 /** Event handler for the library USB Connection event. */
 177 void EVENT_USB_Device_Connect(void)
 178 {
 179         PulseMSRemaining.PingPongLEDPulse = PING_PONG_LED_PULSE_MS;
 180         LEDs_SetAllLEDs(LEDMASK_TX);
 181 }
 182
 183 /** Event handler for the library USB Disconnection event. */
 184 void EVENT_USB_Device_Disconnect(void)
 185 {
 186         PulseMSRemaining.PingPongLEDPulse = 0;
 187         LEDs_SetAllLEDs(LEDS_NO_LEDS);
 188 }
 189
 190 /** Event handler for the library USB Configuration Changed event. */
 191 void EVENT_USB_Device_ConfigurationChanged(void)
 192 {
 193         bool ConfigSuccess = true;
 194
 195         ConfigSuccess &= CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface);
 196
 197         PulseMSRemaining.PingPongLEDPulse = 0;
 198
 199         LEDs_SetAllLEDs(ConfigSuccess ? LEDS_NO_LEDS : LEDMASK_ERROR);
 200 }
 201
 202 /** Event handler for the library USB Unhandled Control Request event. */
 203 void EVENT_USB_Device_UnhandledControlRequest(void)
 204 {
 205         CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
 206 }
 207
 208 /** Event handler for the CDC Class driver Line Encoding Changed event.
 209  *
 210  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 211  */
 212 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 213 {
 214         uint8_t ConfigMask = 0;
 215
 216         switch (CDCInterfaceInfo->State.LineEncoding.ParityType)
 217         {
 218                 case CDC_PARITY_Odd:
 219                         ConfigMask = ((1 << UPM11) | (1 << UPM10));
 220                         break;
 221                 case CDC_PARITY_Even:
 222                         ConfigMask = (1 << UPM11);
 223                         break;
 224         }
 225
 226         if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)
 227           ConfigMask |= (1 << USBS1);
 228
 229         switch (CDCInterfaceInfo->State.LineEncoding.DataBits)
 230         {
 231                 case 6:
 232                         ConfigMask |= (1 << UCSZ10);
 233                         break;
 234                 case 7:
 235                         ConfigMask |= (1 << UCSZ11);
 236                         break;
 237                 case 8:
 238                         ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));
 239                         break;
 240         }
 241
 242         /* Must turn off USART before reconfiguring it, otherwise incorrect operation may occur */
 243         UCSR1B = 0;
 244         UCSR1A = 0;
 245         UCSR1C = 0;
 246
 247         /* Set the new baud rate before configuring the USART */
 248         UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
 249
 250         /* Reconfigure the USART in double speed mode for a wider baud rate range at the expense of accuracy */
 251         UCSR1C = ConfigMask;
 252         UCSR1A = (1 << U2X1);
 253         UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
 254 }
 255
 256 /** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer
 257  *  for later transmission to the host.
 258  */
 259 ISR(USART1_RX_vect, ISR_BLOCK)
 260 {
 261         uint8_t ReceivedByte = UDR1;
 262
 263         if (USB_DeviceState == DEVICE_STATE_Configured)
 264           RingBuffer_Insert(&Tx_Buffer, ReceivedByte);
 265 }
 266
 267 /** Event handler for the CDC Class driver Host-to-Device Line Encoding Changed event.
 268  *
 269  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 270  */
 271 void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 272 {
 273         bool CurrentDTRState = (CDCInterfaceInfo->State.ControlLineStates.HostToDevice & CDC_CONTROL_LINE_OUT_DTR);
 274
 275         /* Check if the DTR line has been asserted - if so, start the target AVR's reset pulse */
 276         if (!(PreviousDTRState) && CurrentDTRState)
 277         {
 278                 LEDs_SetAllLEDs(LEDMASK_BUSY);
 279
 280                 AVR_RESET_LINE_DDR |= AVR_RESET_LINE_MASK;
 281                 PulseMSRemaining.ResetPulse = AVR_RESET_PULSE_MS;
 282         }
 283
 284         PreviousDTRState = CurrentDTRState;
 285 }