Projects/Benito/Benito.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2016.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2016  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 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
  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   = INTERFACE_ID_CDC_CCI,
  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         GlobalInterruptEnable();
  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 #if (ARCH == ARCH_AVR8)
 175         /* Disable watchdog if enabled by bootloader/fuses */
 176         MCUSR &= ~(1 << WDRF);
 177         wdt_disable();
 178
 179         /* Disable clock division */
 180         clock_prescale_set(clock_div_1);
 181 #endif
 182
 183         /* Hardware Initialization */
 184         LEDs_Init();
 185         USB_Init();
 186
 187         /* Millisecond Timer Interrupt */
 188         OCR0A  = (F_CPU / 64 / 1000);
 189         TCCR0A = (1 << WGM01);
 190         TCCR0B = ((1 << CS01) | (1 << CS00));
 191
 192         /* Tristate target /RESET Line */
 193         AVR_RESET_LINE_PORT &= ~AVR_RESET_LINE_MASK;
 194         AVR_RESET_LINE_DDR  &= ~AVR_RESET_LINE_MASK;
 195 }
 196
 197 /** Event handler for the library USB Connection event. */
 198 void EVENT_USB_Device_Connect(void)
 199 {
 200         PulseMSRemaining.PingPongLEDPulse = PING_PONG_LED_PULSE_MS;
 201         LEDs_SetAllLEDs(LEDMASK_TX);
 202 }
 203
 204 /** Event handler for the library USB Disconnection event. */
 205 void EVENT_USB_Device_Disconnect(void)
 206 {
 207         PulseMSRemaining.PingPongLEDPulse = 0;
 208         LEDs_SetAllLEDs(LEDS_NO_LEDS);
 209 }
 210
 211 /** Event handler for the library USB Configuration Changed event. */
 212 void EVENT_USB_Device_ConfigurationChanged(void)
 213 {
 214         bool ConfigSuccess = true;
 215
 216         ConfigSuccess &= CDC_Device_ConfigureEndpoints(&VirtualSerial_CDC_Interface);
 217
 218         PulseMSRemaining.PingPongLEDPulse = 0;
 219
 220         LEDs_SetAllLEDs(ConfigSuccess ? LEDS_NO_LEDS : LEDMASK_ERROR);
 221 }
 222
 223 /** Event handler for the USB_ControlRequest event. This is used to catch and process control requests sent to
 224  *  the device from the USB host before passing along unhandled control requests to the library for processing
 225  *  internally.
 226  */
 227 void EVENT_USB_Device_ControlRequest(void)
 228 {
 229         CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);
 230 }
 231
 232 /** Event handler for the CDC Class driver Line Encoding Changed event.
 233  *
 234  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 235  */
 236 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 237 {
 238         uint8_t ConfigMask = 0;
 239
 240         switch (CDCInterfaceInfo->State.LineEncoding.ParityType)
 241         {
 242                 case CDC_PARITY_Odd:
 243                         ConfigMask = ((1 << UPM11) | (1 << UPM10));
 244                         break;
 245                 case CDC_PARITY_Even:
 246                         ConfigMask = (1 << UPM11);
 247                         break;
 248         }
 249
 250         if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)
 251           ConfigMask |= (1 << USBS1);
 252
 253         switch (CDCInterfaceInfo->State.LineEncoding.DataBits)
 254         {
 255                 case 6:
 256                         ConfigMask |= (1 << UCSZ10);
 257                         break;
 258                 case 7:
 259                         ConfigMask |= (1 << UCSZ11);
 260                         break;
 261                 case 8:
 262                         ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));
 263                         break;
 264         }
 265
 266         /* Must turn off USART before reconfiguring it, otherwise incorrect operation may occur */
 267         UCSR1B = 0;
 268         UCSR1A = 0;
 269         UCSR1C = 0;
 270
 271         /* Set the new baud rate before configuring the USART */
 272         UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);
 273
 274         /* Reconfigure the USART in double speed mode for a wider baud rate range at the expense of accuracy */
 275         UCSR1C = ConfigMask;
 276         UCSR1A = (1 << U2X1);
 277         UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));
 278 }
 279
 280 /** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer
 281  *  for later transmission to the host.
 282  */
 283 ISR(USART1_RX_vect, ISR_BLOCK)
 284 {
 285         uint8_t ReceivedByte = UDR1;
 286
 287         if (USB_DeviceState == DEVICE_STATE_Configured)
 288           RingBuffer_Insert(&USARTtoUSB_Buffer, ReceivedByte);
 289 }
 290
 291 /** Event handler for the CDC Class driver Host-to-Device Line Encoding Changed event.
 292  *
 293  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced
 294  */
 295 void EVENT_CDC_Device_ControLineStateChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)
 296 {
 297         static bool PreviousDTRState = false;
 298         bool        CurrentDTRState  = (CDCInterfaceInfo->State.ControlLineStates.HostToDevice & CDC_CONTROL_LINE_OUT_DTR);
 299
 300         /* Check if the DTR line has been asserted - if so, start the target AVR's reset pulse */
 301         if (!(PreviousDTRState) && CurrentDTRState)
 302         {
 303                 LEDs_SetAllLEDs(LEDMASK_BUSY);
 304
 305                 AVR_RESET_LINE_DDR |= AVR_RESET_LINE_MASK;
 306                 PulseMSRemaining.ResetPulse = AVR_RESET_PULSE_MS;
 307         }
 308
 309         PreviousDTRState = CurrentDTRState;
 310 }
 311