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                         if (!(--FlushPeriodRemaining) || (Tx_Buffer.Count > 200))
 131                         {
 132                                 /* Echo bytes from the target to the host via the virtual serial port */
 133                                 if (Tx_Buffer.Count)
 134                                 {
 135                                         while (Tx_Buffer.Count)
 136                                           CDC_Device_SendByte(&VirtualSerial_CDC_Interface, RingBuffer_AtomicRemove(&Tx_Buffer));
 137
 138                                         LEDs_TurnOnLEDs(LEDMASK_RX);
 139                                         PulseMSRemaining.RxLEDPulse = TX_RX_LED_PULSE_MS;
 140                                 }
 141
 142                                 FlushPeriodRemaining = RECEIVE_BUFFER_FLUSH_MS;
 143                         }
 144
 145                         /* Clear the millisecond timer CTC flag (cleared by writing logic one to the register) */
 146                         TIFR0 |= (1 << OCF0A);
 147                 }
 148
 149                 CDC_Device_USBTask(&VirtualSerial_CDC_Interface);
 150                 USB_USBTask();
 151         }
 152 }
 153
 154 /** Configures the board hardware and chip peripherals for the demo's functionality. */
 155 void SetupHardware(void)
 156 {
 157         /* Disable watchdog if enabled by bootloader/fuses */
 158         MCUSR &= ~(1 << WDRF);
 159         wdt_disable();
 160
 161         /* Hardware Initialization */
 162         LEDs_Init();
 163         USB_Init();
 164
 165         /* Millisecond Timer Interrupt */
 166         OCR0A  = (F_CPU / 64 / 1000);
 167         TCCR0A = (1 << WGM01);
 168         TCCR0B = ((1 << CS01) | (1 << CS00));
 169
 170         /* Tristate target /RESET Line */
 171         AVR_RESET_LINE_PORT &= ~AVR_RESET_LINE_MASK;
 172         AVR_RESET_LINE_DDR  &= ~AVR_RESET_LINE_MASK;
 173 }
 174
 175 /** Event handler for the library USB Connection event. */
 176 void EVENT_USB_Device_Connect(void)
 177 {
 178         PulseMSRemaining.PingPongLEDPulse = PING_PONG_LED_PULSE_MS;
 179         LEDs_SetAllLEDs(LEDMASK_TX);
 180 }
 181
 182 /** Event handler for the library USB Disconnection event. */
 183 void EVENT_USB_Device_Disconnect(void)
 184 {
 185         PulseMSRemaining.PingPongLEDPulse = 0;
 186         LEDs_SetAllLEDs(LEDS_NO_LEDS);
 187 }
 188
 189 /** Event handler for the library USB Configuration Changed event. */
 190 void EVENT_USB_Device_ConfigurationChanged(void)
 191 {
 192         PulseMSRemaining.PingPongLEDPulse = 0;
 193         LEDs_SetAllLEDs(LEDS_NO_LEDS);
 194
 195         if (!(CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface)))
 196           LEDs_SetAllLEDs(LEDMASK_ERROR);
 197 }
 198
 199 /** Event handler for the library USB Unhandled Control Request event. */
 200 void EVENT_USB_Device_UnhandledControlRequest(void)
 201 {
 202         CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
 203 }
 204
 205 /** Event handler for the CDC Class driver Line Encoding Changed event.
 206  *
 207  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 208  */
 209 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 210 {
 211         uint8_t ConfigMask = 0;
 212
 213         switch (CDCInterfaceInfo->State.LineEncoding.ParityType)
 214         {
 215                 case CDC_PARITY_Odd:
 216                         ConfigMask = ((1 << UPM11) | (1 << UPM10));
 217                         break;
 218                 case CDC_PARITY_Even:
 219                         ConfigMask = (1 << UPM11);
 220                         break;
 221         }
 222
 223         if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)
 224           ConfigMask |= (1 << USBS1);
 225
 226         switch (CDCInterfaceInfo->State.LineEncoding.DataBits)
 227         {
 228                 case 6:
 229                         ConfigMask |= (1 << UCSZ10);
 230                         break;
 231                 case 7:
 232                         ConfigMask |= (1 << UCSZ11);
 233                         break;
 234                 case 8:
 235                         ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));
 236                         break;
 237         }
 238
 239         /* Must turn off USART before reconfiguring it, otherwise incorrect operation may occur */
 240         UCSR1B = 0;
 241         UCSR1A = 0;
 242         UCSR1C = 0;
 243
 244         /* Set the new baud rate before configuring the USART */
 245         UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
 246
 247         /* Reconfigure the USART in double speed mode for a wider baud rate range at the expense of accuracy */
 248         UCSR1C = ConfigMask;
 249         UCSR1A = (1 << U2X1);
 250         UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
 251 }
 252
 253 /** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer
 254  *  for later transmission to the host.
 255  */
 256 ISR(USART1_RX_vect, ISR_BLOCK)
 257 {
 258         uint8_t ReceivedByte = UDR1;
 259
 260         if (USB_DeviceState == DEVICE_STATE_Configured)
 261           RingBuffer_Insert(&Tx_Buffer, ReceivedByte);
 262 }
 263
 264 /** Event handler for the CDC Class driver Host-to-Device Line Encoding Changed event.
 265  *
 266  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 267  */
 268 void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 269 {
 270         bool CurrentDTRState = (CDCInterfaceInfo->State.ControlLineStates.HostToDevice & CDC_CONTROL_LINE_OUT_DTR);
 271
 272         /* Check if the DTR line has been asserted - if so, start the target AVR's reset pulse */
 273         if (!(PreviousDTRState) && CurrentDTRState)
 274         {
 275                 LEDs_SetAllLEDs(LEDMASK_BUSY);
 276
 277                 AVR_RESET_LINE_DDR |= AVR_RESET_LINE_MASK;
 278                 PulseMSRemaining.ResetPulse = AVR_RESET_PULSE_MS;
 279         }
 280
 281         PreviousDTRState = CurrentDTRState;
 282 }