WDDDS2021の初心者講座で使用してArduino用のコード

WDDDS2021-arduino

/*
 * UsbControllerActivity.java
 * This file is part of UsbController
 *
 * Copyright (C) 2012 - Manuel Di Cerbo
 *
 * UsbController is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * UsbController is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with UsbController. If not, see <http://www.gnu.org/licenses/>.
 */

/*
 * main.c
 *  (c) Nexus-Computing GmbH Switzerland
 *  Created on: Feb 02, 2012
 *      Author: Manuel Di Cerbo
 */
#include <stdio.h>
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>

#define LED PB5 // LED is on Pin 13 or Pin 5 of Port B
/*
 * UART-Initialization from www.mikrocontroller.net
 * Hint: They are awesome! :-)
 */

#ifndef F_CPU
#warning "F_CPU was not defined, defining it now as 16000000"
#define F_CPU 16000000UL
#endif

#define BAUD 9600UL      // baud rate
// Calculations
#define UBRR_VAL ((F_CPU+BAUD*8)/(BAUD*16)-1)   // smart rounding
#define BAUD_REAL (F_CPU/(16*(UBRR_VAL+1)))     // real baud rate
#define BAUD_ERROR ((BAUD_REAL*1000)/BAUD) // error in parts per mill, 1000 = no error
#if ((BAUD_ERROR<990) || (BAUD_ERROR>1010))
#error Error in baud rate greater than 1%!
#endif

#define RX_MAX sizeof(command_t)

// コマンド構造体の定義
typedef struct  command_s {
    uint8_t     command;
    uint8_t     value;
}               command_t;

// コマンド種別
typedef enum {
  COMMAND_DEFAULT = 0,
  COMMAND_SEND_INTENSITY = 1
} commandEnum;

void uart_init(void) {
  UBRR0H = UBRR_VAL >> 8;
  UBRR0L = UBRR_VAL & 0xFF;

  UCSR0C = (0 << UMSEL01) | (0 << UMSEL00) | (1 << UCSZ01) | (1 << UCSZ00); // asynchron 8N1
  UCSR0B |= (1 << RXEN0); // enable UART RX
  UCSR0B |= (1 << TXEN0); // enable UART TX
  UCSR0B |= (1 << RXCIE0); //interrupt enable
}

/* Receive symbol, not necessary for this example, using interrupt instead*/
uint8_t uart_getc(void) {
  while (!(UCSR0A & (1 << RXC0)))
    // wait until symbol is ready
    ;
  return UDR0; // return symbol
}

uint8_t uart_putc(unsigned char data) {
  /* Wait for empty transmit buffer */
  while (!(UCSR0A & (1 << UDRE0)))
    ;
  /* Put data into buffer, sends the data */
  UDR0 = data;
  return 0;
}


void initIO(void) {
  DDRD |= (1 << DDD3);
  DDRB = 0xff; //all out
}


volatile uint8_t data = 10;
volatile uint8_t RxFlag = 0;
volatile uint8_t index = 0;
volatile command_t data2 = { .command = 0, .value = 0 };
volatile uint8_t buffer[sizeof(command_t)];

int main(void) {
  initIO();
  uart_init();
  sei();

  uint8_t i = 0;
  volatile uint8_t pause = 100;
  for(;;) {
    if (RxFlag == 1) {
      data2 = *(command_t *)buffer;
      // COMMAND_SEND_INTENSITYだった場合、LEDの強さを調整する
      switch (data2.command) {
        case COMMAND_SEND_INTENSITY:
          pause = data2.value;
          break;
      }
      RxFlag = 0;
    }
    
    PORTB |= (1 << LED);
    for(i = 0; i < pause; i++)
      _delay_us(10);
    PORTB &= ~(1 << LED);
    for(i = 0; i < 255-pause; i++)
      _delay_us(10);
  }
  return 0; // never reached
}

ISR(USART_RX_vect) {//attention to the name and argument here, won't work otherwise
  buffer[index] = UDR0;//UDR0 needs to be read
  ++index;
  if (index == RX_MAX) {
    index = 0;
    RxFlag = 1;
  }
}