如何使用Arduino超声波传感器连接到Arduino UNO，以使用Pyfirmata或Python测量距离？

Question

这是我在Arduino的代码。就我而言，Pyfirmata没有PulseIn函数，那么我如何才能绕过这个障碍呢？当传感器感应到物体距离它20厘米或更小时，我想打开LED

// defines pins numbers
const int trigPin = 12;
const int echoPin = 11;
int LED = 5;
// defines variables
long duration;
int distance;

void setup() {
    pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
    pinMode(echoPin, INPUT); // Sets the echoPin as an Input
    Serial.begin(9600); // Starts the serial communication
    pinMode (LED,OUTPUT);
}

void loop() {
    // Clears the trigPin
    digitalWrite(trigPin, LOW);
    delayMicroseconds(2);
    // Sets the trigPin on HIGH state for 10 micro seconds
    digitalWrite(trigPin, HIGH);
    delayMicroseconds(10);
    digitalWrite(trigPin, LOW);
    // Reads the echoPin, returns the sound wave travel time in microseconds
    duration = pulseIn(echoPin, HIGH);
    // Calculating the distance
    distance= duration*0.034/2;
    // Prints the distance on the Serial Monitor
    Serial.print("Distance: ");
    Serial.println(distance);

    if (distance <=20){
      digitalWrite(LED,HIGH);
    }
    else{
      digitalWrite (LED,LOW);
    }
}

Answer 1

我遇到了同样的问题，并试图解决。我发现你的问题没有答案：D。我花了两天的时间才发现我像一只饥饿的狼一样全力以赴。 这是你需要做的

首先是一些背景故事。 PyFirmata是一个库，它充当Python和Arduino AVR之间的桥梁。这意味着为了使函数正常工作，您需要在eh反手程序中用两种语言（AVR和Python）定义它们，以便它们可以用相同的术语进行通信。 AVR中的文件是StandardFirmata.ino。Python中的文件是pyFirmata.py。从这里你可以看到更多。当程序运行时，这些文件彼此通信

1. https://github.com/tino/pyFirmata/pull/45/files
2. https://github.com/jgautier/arduino-1/tree/pulseIn

一些人试图添加一个脉冲输入功能来计算与超声波传感器的距离，结果很好。要使其正常工作，您必须手动更新arduino中的standardfirmata文件和Python中的pyFirmata文件，以便在上面链接的代码中添加PULSE_。以下是步骤

1. 在Arduino IDE中打开StandardFirmata草图
2. 复制粘贴此代码以替换旧代码。这将在我从上面的链接中提取并添加到我的standardfirmata的特征中添加PULSE_

/*
 * Firmata is a generic protocol for communicating with microcontrollers
 * from software on a host computer. It is intended to work with
 * any host computer software package.
 *
 * To download a host software package, please clink on the following link
 * to open the download page in your default browser.
 *
 * http://firmata.org/wiki/Download
 */
/*
  Copyright (C) 2006-2008 Hans-Christoph Steiner.  All rights reserved.
  Copyright (C) 2010-2011 Paul Stoffregen.  All rights reserved.
  Copyright (C) 2009 Shigeru Kobayashi.  All rights reserved.
  Copyright (C) 2009-2011 Jeff Hoefs.  All rights reserved.
  
  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.
 
  See file LICENSE.txt for further informations on licensing terms.
  formatted using the GNU C formatting and indenting
*/
/* 
 * TODO: use Program Control to load stored profiles from EEPROM
 */
#include <Servo.h>
#include <Wire.h>
#include <Firmata.h>
// move the following defines to Firmata.h?
#define I2C_WRITE B00000000
#define I2C_READ B00001000
#define I2C_READ_CONTINUOUSLY B00010000
#define I2C_STOP_READING B00011000
#define I2C_READ_WRITE_MODE_MASK B00011000
#define I2C_10BIT_ADDRESS_MODE_MASK B00100000
#define MAX_QUERIES               8
#define MINIMUM_SAMPLING_INTERVAL 10
#define REGISTER_NOT_SPECIFIED    -1
#define PULSE_IN                  0x74 // send a pulse in command

/*==============================================================================
 * GLOBAL VARIABLES
 *============================================================================*/
/* Ultrasonic Distance Measurement variables */
# include "LiquidCrystal.h"  //lcd libary                                       
LiquidCrystal lcd(22, 23, 24, 25, 26, 27);   //LCD object Parameters: (rs, enable, d4, d5, d6, d7)
const int trigPin = 35; //trig pin connection 
const int echoPin = 34;  //echopin connection 
long duration;
int distanceCm;
float liquid;
/* analog inputs */
int analogInputsToReport = 0; // bitwise array to store pin reporting
/* digital input ports */
byte reportPINs[TOTAL_PORTS];       // 1 = report this port, 0 = silence
byte previousPINs[TOTAL_PORTS];     // previous 8 bits sent
/* pins configuration */
byte pinConfig[TOTAL_PINS];         // configuration of every pin
byte portConfigInputs[TOTAL_PORTS]; // each bit: 1 = pin in INPUT, 0 = anything else
int pinState[TOTAL_PINS];           // any value that has been written
/* timer variables */
unsigned long currentMillis;        // store the current value from millis()
unsigned long previousMillis;       // for comparison with currentMillis
int samplingInterval = 19;          // how often to run the main loop (in ms)
/* i2c data */
struct i2c_device_info {
  byte addr;
  byte reg;
  byte bytes;
};
/* for i2c read continuous more */
i2c_device_info query[MAX_QUERIES];
byte i2cRxData[32];
boolean isI2CEnabled = false;
signed char queryIndex = -1;
unsigned int i2cReadDelayTime = 0;  // default delay time between i2c read request and Wire.requestFrom()
Servo servos[MAX_SERVOS];
/*==============================================================================
 * FUNCTIONS
 *============================================================================*/
void readAndReportData(byte address, int theRegister, byte numBytes) {
  // allow I2C requests that don't require a register read
  // for example, some devices using an interrupt pin to signify new data available
  // do not always require the register read so upon interrupt you call Wire.requestFrom()  
  if (theRegister != REGISTER_NOT_SPECIFIED) {
    Wire.beginTransmission(address);
    #if ARDUINO >= 100
    Wire.write((byte)theRegister);
    #else
    Wire.send((byte)theRegister);
    #endif
    Wire.endTransmission();
    delayMicroseconds(i2cReadDelayTime);  // delay is necessary for some devices such as WiiNunchuck
  } else {
    theRegister = 0;  // fill the register with a dummy value
  }
  Wire.requestFrom(address, numBytes);  // all bytes are returned in requestFrom
  // check to be sure correct number of bytes were returned by slave
  if(numBytes == Wire.available()) {
    i2cRxData[0] = address;
    i2cRxData[1] = theRegister;
    for (int i = 0; i < numBytes; i++) {
      #if ARDUINO >= 100
      i2cRxData[2 + i] = Wire.read();
      #else
      i2cRxData[2 + i] = Wire.receive();
      #endif
    }
  }
  else {
    if(numBytes > Wire.available()) {
      Firmata.sendString("I2C Read Error: Too many bytes received");
    } else {
      Firmata.sendString("I2C Read Error: Too few bytes received"); 
    }
  }
  // send slave address, register and received bytes
  Firmata.sendSysex(SYSEX_I2C_REPLY, numBytes + 2, i2cRxData);
}
void outputPort(byte portNumber, byte portValue, byte forceSend)
{
  // pins not configured as INPUT are cleared to zeros
  portValue = portValue & portConfigInputs[portNumber];
  // only send if the value is different than previously sent
  if(forceSend || previousPINs[portNumber] != portValue) {
    Firmata.sendDigitalPort(portNumber, portValue);
    previousPINs[portNumber] = portValue;
  }
}
/*                                       -
 * check all the active digital inputs for change of state, then add any events
 * to the Serial output queue using Serial.print() */
void checkDigitalInputs(void)
{
  /* Using non-looping code allows constants to be given to readPort().
   * The compiler will apply substantial optimizations if the inputs
   * to readPort() are compile-time constants. */
  if (TOTAL_PORTS > 0 && reportPINs[0]) outputPort(0, readPort(0, portConfigInputs[0]), false);
  if (TOTAL_PORTS > 1 && reportPINs[1]) outputPort(1, readPort(1, portConfigInputs[1]), false);
  if (TOTAL_PORTS > 2 && reportPINs[2]) outputPort(2, readPort(2, portConfigInputs[2]), false);
  if (TOTAL_PORTS > 3 && reportPINs[3]) outputPort(3, readPort(3, portConfigInputs[3]), false);
  if (TOTAL_PORTS > 4 && reportPINs[4]) outputPort(4, readPort(4, portConfigInputs[4]), false);
  if (TOTAL_PORTS > 5 && reportPINs[5]) outputPort(5, readPort(5, portConfigInputs[5]), false);
  if (TOTAL_PORTS > 6 && reportPINs[6]) outputPort(6, readPort(6, portConfigInputs[6]), false);
  if (TOTAL_PORTS > 7 && reportPINs[7]) outputPort(7, readPort(7, portConfigInputs[7]), false);
  if (TOTAL_PORTS > 8 && reportPINs[8]) outputPort(8, readPort(8, portConfigInputs[8]), false);
  if (TOTAL_PORTS > 9 && reportPINs[9]) outputPort(9, readPort(9, portConfigInputs[9]), false);
  if (TOTAL_PORTS > 10 && reportPINs[10]) outputPort(10, readPort(10, portConfigInputs[10]), false);
  if (TOTAL_PORTS > 11 && reportPINs[11]) outputPort(11, readPort(11, portConfigInputs[11]), false);
  if (TOTAL_PORTS > 12 && reportPINs[12]) outputPort(12, readPort(12, portConfigInputs[12]), false);
  if (TOTAL_PORTS > 13 && reportPINs[13]) outputPort(13, readPort(13, portConfigInputs[13]), false);
  if (TOTAL_PORTS > 14 && reportPINs[14]) outputPort(14, readPort(14, portConfigInputs[14]), false);
  if (TOTAL_PORTS > 15 && reportPINs[15]) outputPort(15, readPort(15, portConfigInputs[15]), false);
}
//                                       -
/* sets the pin mode to the correct state and sets the relevant bits in the
 * two bit-arrays that track Digital I/O and PWM status
 */
void setPinModeCallback(byte pin, int mode)
{
  if (pinConfig[pin] == I2C && isI2CEnabled && mode != I2C) {
    // disable i2c so pins can be used for other functions
    // the following if statements should reconfigure the pins properly
    disableI2CPins();
  }
  if (IS_PIN_SERVO(pin) && mode != SERVO && servos[PIN_TO_SERVO(pin)].attached()) {
    servos[PIN_TO_SERVO(pin)].detach();
  }
  if (IS_PIN_ANALOG(pin)) {
    reportAnalogCallback(PIN_TO_ANALOG(pin), mode == ANALOG ? 1 : 0); // turn on/off reporting
  }
  if (IS_PIN_DIGITAL(pin)) {
    if (mode == INPUT) {
      portConfigInputs[pin/8] |= (1 << (pin & 7));
    } else {
      portConfigInputs[pin/8] &= ~(1 << (pin & 7));
    }
  }
  pinState[pin] = 0;
  switch(mode) {
  case ANALOG:
    if (IS_PIN_ANALOG(pin)) {
      if (IS_PIN_DIGITAL(pin)) {
        pinMode(PIN_TO_DIGITAL(pin), INPUT); // disable output driver
        digitalWrite(PIN_TO_DIGITAL(pin), LOW); // disable internal pull-ups
      }
      pinConfig[pin] = ANALOG;
    }
    break;
  case INPUT:
    if (IS_PIN_DIGITAL(pin)) {
      pinMode(PIN_TO_DIGITAL(pin), INPUT); // disable output driver
      digitalWrite(PIN_TO_DIGITAL(pin), LOW); // disable internal pull-ups
      pinConfig[pin] = INPUT;
    }
    break;
  case OUTPUT:
    if (IS_PIN_DIGITAL(pin)) {
      digitalWrite(PIN_TO_DIGITAL(pin), LOW); // disable PWM
      pinMode(PIN_TO_DIGITAL(pin), OUTPUT);
      pinConfig[pin] = OUTPUT;
    }
    break;
  case PWM:
    if (IS_PIN_PWM(pin)) {
      pinMode(PIN_TO_PWM(pin), OUTPUT);
      analogWrite(PIN_TO_PWM(pin), 0);
      pinConfig[pin] = PWM;
    }
    break;
  case SERVO:
    if (IS_PIN_SERVO(pin)) {
      pinConfig[pin] = SERVO;
      if (!servos[PIN_TO_SERVO(pin)].attached()) {
          servos[PIN_TO_SERVO(pin)].attach(PIN_TO_DIGITAL(pin));
      }
    }
    break;
  case I2C:
    if (IS_PIN_I2C(pin)) {
      // mark the pin as i2c
      // the user must call I2C_CONFIG to enable I2C for a device
      pinConfig[pin] = I2C;
    }
    break;
  default:
    Firmata.sendString("Unknown pin mode"); // TODO: put error msgs in EEPROM
  }
  // TODO: save status to EEPROM here, if changed
}
void analogWriteCallback(byte pin, int value)
{
  if (pin < TOTAL_PINS) {
    switch(pinConfig[pin]) {
    case SERVO:
      if (IS_PIN_SERVO(pin))
        servos[PIN_TO_SERVO(pin)].write(value);
        pinState[pin] = value;
      break;
    case PWM:
      if (IS_PIN_PWM(pin))
        analogWrite(PIN_TO_PWM(pin), value);
        pinState[pin] = value;
      break;
    }
  }
}
void digitalWriteCallback(byte port, int value)
{
  byte pin, lastPin, mask=1, pinWriteMask=0;
  if (port < TOTAL_PORTS) {
    // create a mask of the pins on this port that are writable.
    lastPin = port*8+8;
    if (lastPin > TOTAL_PINS) lastPin = TOTAL_PINS;
    for (pin=port*8; pin < lastPin; pin++) {
      // do not disturb non-digital pins (eg, Rx & Tx)
      if (IS_PIN_DIGITAL(pin)) {
        // only write to OUTPUT and INPUT (enables pullup)
        // do not touch pins in PWM, ANALOG, SERVO or other modes
        if (pinConfig[pin] == OUTPUT || pinConfig[pin] == INPUT) {
          pinWriteMask |= mask;
          pinState[pin] = ((byte)value & mask) ? 1 : 0;
        }
      }
      mask = mask << 1;
    }
    writePort(port, (byte)value, pinWriteMask);
  }
}
//                                       -
/* sets bits in a bit array (int) to toggle the reporting of the analogIns
 */
//void FirmataClass::setAnalogPinReporting(byte pin, byte state) {
//}
void reportAnalogCallback(byte analogPin, int value)
{
  if (analogPin < TOTAL_ANALOG_PINS) {
    if(value == 0) {
      analogInputsToReport = analogInputsToReport &~ (1 << analogPin);
    } else {
      analogInputsToReport = analogInputsToReport | (1 << analogPin);
    }
  }
  // TODO: save status to EEPROM here, if changed
}
void reportDigitalCallback(byte port, int value)
{
  if (port < TOTAL_PORTS) {
    reportPINs[port] = (byte)value;
  }
  // do not disable analog reporting on these 8 pins, to allow some
  // pins used for digital, others analog.  Instead, allow both types
  // of reporting to be enabled, but check if the pin is configured
  // as analog when sampling the analog inputs.  Likewise, while
  // scanning digital pins, portConfigInputs will mask off values from any
  // pins configured as analog
}
/*==============================================================================
 * SYSEX-BASED commands
 *============================================================================*/
void sysexCallback(byte command, byte argc, byte *argv)
{
  byte mode;
  byte slaveAddress;
  byte slaveRegister;
  byte data;
  unsigned int delayTime; 
  
  switch(command) {
  case I2C_REQUEST:
    mode = argv[1] & I2C_READ_WRITE_MODE_MASK;
    if (argv[1] & I2C_10BIT_ADDRESS_MODE_MASK) {
      Firmata.sendString("10-bit addressing mode is not yet supported");
      return;
    }
    else {
      slaveAddress = argv[0];
    }
    switch(mode) {
    case I2C_WRITE:
      Wire.beginTransmission(slaveAddress);
      for (byte i = 2; i < argc; i += 2) {
        data = argv[i] + (argv[i + 1] << 7);
        #if ARDUINO >= 100
        Wire.write(data);
        #else
        Wire.send(data);
        #endif
      }
      Wire.endTransmission();
      delayMicroseconds(70);
      break;
    case I2C_READ:
      if (argc == 6) {
        // a slave register is specified
        slaveRegister = argv[2] + (argv[3] << 7);
        data = argv[4] + (argv[5] << 7);  // bytes to read
        readAndReportData(slaveAddress, (int)slaveRegister, data);
      }
      else {
        // a slave register is NOT specified
        data = argv[2] + (argv[3] << 7);  // bytes to read
        readAndReportData(slaveAddress, (int)REGISTER_NOT_SPECIFIED, data);
      }
      break;
    case I2C_READ_CONTINUOUSLY:
      if ((queryIndex + 1) >= MAX_QUERIES) {
        // too many queries, just ignore
        Firmata.sendString("too many queries");
        break;
      }
      queryIndex++;
      query[queryIndex].addr = slaveAddress;
      query[queryIndex].reg = argv[2] + (argv[3] << 7);
      query[queryIndex].bytes = argv[4] + (argv[5] << 7);
      break;
    case I2C_STOP_READING:
      byte queryIndexToSkip;      
      // if read continuous mode is enabled for only 1 i2c device, disable
      // read continuous reporting for that device
      if (queryIndex <= 0) {
        queryIndex = -1;        
      } else {
        // if read continuous mode is enabled for multiple devices,
        // determine which device to stop reading and remove it's data from
        // the array, shifiting other array data to fill the space
        for (byte i = 0; i < queryIndex + 1; i++) {
          if (query[i].addr = slaveAddress) {
            queryIndexToSkip = i;
            break;
          }
        }
        
        for (byte i = queryIndexToSkip; i<queryIndex + 1; i++) {
          if (i < MAX_QUERIES) {
            query[i].addr = query[i+1].addr;
            query[i].reg = query[i+1].addr;
            query[i].bytes = query[i+1].bytes; 
          }
        }
        queryIndex ;
      }
      break;
    default:
      break;
    }
    break;
  case I2C_CONFIG:
    delayTime = (argv[0] + (argv[1] << 7));
    if(delayTime > 0) {
      i2cReadDelayTime = delayTime;
    }
    if (!isI2CEnabled) {
      enableI2CPins();
    }
    
    break;
  case SERVO_CONFIG:
    if(argc > 4) {
      // these vars are here for clarity, they'll optimized away by the compiler
      byte pin = argv[0];
      int minPulse = argv[1] + (argv[2] << 7);
      int maxPulse = argv[3] + (argv[4] << 7);
      if (IS_PIN_SERVO(pin)) {
        if (servos[PIN_TO_SERVO(pin)].attached())
          servos[PIN_TO_SERVO(pin)].detach();
        servos[PIN_TO_SERVO(pin)].attach(PIN_TO_DIGITAL(pin), minPulse, maxPulse);
        setPinModeCallback(pin, SERVO);
      }
    }
    break;
  case SAMPLING_INTERVAL:
    if (argc > 1) {
      samplingInterval = argv[0] + (argv[1] << 7);
      if (samplingInterval < MINIMUM_SAMPLING_INTERVAL) {
        samplingInterval = MINIMUM_SAMPLING_INTERVAL;
      }      
    } else {
      //Firmata.sendString("Not enough data");
    }
    break;
  case EXTENDED_ANALOG:
    if (argc > 1) {
      int val = argv[1];
      if (argc > 2) val |= (argv[2] << 7);
      if (argc > 3) val |= (argv[3] << 14);
      analogWriteCallback(argv[0], val);
    }
    break;
  case CAPABILITY_QUERY:
    Serial.write(START_SYSEX);
    Serial.write(CAPABILITY_RESPONSE);
    for (byte pin=0; pin < TOTAL_PINS; pin++) {
      if (IS_PIN_DIGITAL(pin)) {
        Serial.write((byte)INPUT);
        Serial.write(1);
        Serial.write((byte)OUTPUT);
        Serial.write(1);
      }
      if (IS_PIN_ANALOG(pin)) {
        Serial.write(ANALOG);
        Serial.write(10);
      }
      if (IS_PIN_PWM(pin)) {
        Serial.write(PWM);
        Serial.write(8);
      }
      if (IS_PIN_SERVO(pin)) {
        Serial.write(SERVO);
        Serial.write(14);
      }
      if (IS_PIN_I2C(pin)) {
        Serial.write(I2C);
        Serial.write(1);  // to do: determine appropriate value 
      }
      Serial.write(127);
    }
    Serial.write(END_SYSEX);
    break;
  case PIN_STATE_QUERY:
    if (argc > 0) {
      byte pin=argv[0];
      Serial.write(START_SYSEX);
      Serial.write(PIN_STATE_RESPONSE);
      Serial.write(pin);
      if (pin < TOTAL_PINS) {
        Serial.write((byte)pinConfig[pin]);
    Serial.write((byte)pinState[pin] & 0x7F);
    if (pinState[pin] & 0xFF80) Serial.write((byte)(pinState[pin] >> 7) & 0x7F);
    if (pinState[pin] & 0xC000) Serial.write((byte)(pinState[pin] >> 14) & 0x7F);
      }
      Serial.write(END_SYSEX);
    }
    break;
  case ANALOG_MAPPING_QUERY:
    Serial.write(START_SYSEX);
    Serial.write(ANALOG_MAPPING_RESPONSE);
    for (byte pin=0; pin < TOTAL_PINS; pin++) {
      Serial.write(IS_PIN_ANALOG(pin) ? PIN_TO_ANALOG(pin) : 127);
    }
    Serial.write(END_SYSEX);
    break;
  case PULSE_IN:
    unsigned long duration;
    byte responseArray[5];
    byte timeoutArray[4] = {
        (argv[2] & 0x7F) | ((argv[3] & 0x7F) << 7)
       ,(argv[4] & 0x7F) | ((argv[5] & 0x7F) << 7)
       ,(argv[6] & 0x7F) | ((argv[7] & 0x7F) << 7)
       ,(argv[8] & 0x7F) | ((argv[9] & 0x7F) << 7)
    };
    unsigned long timeout = ((unsigned long)timeoutArray[0] << 24)
              | ((unsigned long)timeoutArray[1] << 16)
              | ((unsigned long)timeoutArray[2] << 8)
              | ((unsigned long)timeoutArray[3]);
    duration = pulseIn(argv[0],argv[1],timeout);
    responseArray[0] = argv[0];
    responseArray[1] = ((timeout >> 24) & 0xFF) ;
    responseArray[2] = ((timeout >> 16) & 0xFF) ;
    responseArray[3] = ((timeout >> 8) & 0xFF);
    responseArray[4] = ((timeout & 0xFF));
    Firmata.sendSysex(PULSE_IN,5,responseArray);
  }
}

void enableI2CPins()
{
  byte i;
  // is there a faster way to do this? would probaby require importing 
  // Arduino.h to get SCL and SDA pins
  for (i=0; i < TOTAL_PINS; i++) {
    if(IS_PIN_I2C(i)) {
      // mark pins as i2c so they are ignore in non i2c data requests
      setPinModeCallback(i, I2C);
    } 
  }
   
  isI2CEnabled = true; 
  
  // is there enough time before the first I2C request to call this here?
  Wire.begin();
}
/* disable the i2c pins so they can be used for other functions */
void disableI2CPins() {
    isI2CEnabled = false;
    // disable read continuous mode for all devices
    queryIndex = -1;
    // uncomment the following if or when the end() method is added to Wire library
    // Wire.end();
}
/*==============================================================================
 * SETUP()
 *============================================================================*/
void systemResetCallback()
{
  // initialize a defalt state
  // TODO: option to load config from EEPROM instead of default
  if (isI2CEnabled) {
    disableI2CPins();
  }
  for (byte i=0; i < TOTAL_PORTS; i++) {
    reportPINs[i] = false;      // by default, reporting off
    portConfigInputs[i] = 0;    // until activated
    previousPINs[i] = 0;
  }
  // pins with analog capability default to analog input
  // otherwise, pins default to digital output
  for (byte i=0; i < TOTAL_PINS; i++) {
    if (IS_PIN_ANALOG(i)) {
      // turns off pullup, configures everything
      setPinModeCallback(i, ANALOG);
    } else {
      // sets the output to 0, configures portConfigInputs
      setPinModeCallback(i, OUTPUT);
    }
  }
  // by default, do not report any analog inputs
  analogInputsToReport = 0;
  /* send digital inputs to set the initial state on the host computer,
   * since once in the loop(), this firmware will only send on change */
  /*
  TODO: this can never execute, since no pins default to digital input
        but it will be needed when/if we support EEPROM stored config
  for (byte i=0; i < TOTAL_PORTS; i++) {
    outputPort(i, readPort(i, portConfigInputs[i]), true);
  }
  */
}
void setup() 
{
  Firmata.setFirmwareVersion(FIRMATA_MAJOR_VERSION, FIRMATA_MINOR_VERSION);
  Firmata.attach(ANALOG_MESSAGE, analogWriteCallback);
  Firmata.attach(DIGITAL_MESSAGE, digitalWriteCallback);
  Firmata.attach(REPORT_ANALOG, reportAnalogCallback);
  Firmata.attach(REPORT_DIGITAL, reportDigitalCallback);
  Firmata.attach(SET_PIN_MODE, setPinModeCallback);
  Firmata.attach(START_SYSEX, sysexCallback);
  Firmata.attach(SYSTEM_RESET, systemResetCallback);
  Firmata.begin(57600);
  systemResetCallback();  // reset to default config

 /*Distance measurement with Ultrasonic Sensor */
  Serial.begin(9600);
  lcd.begin(16,2);                                                   
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  lcd.setCursor(0,0);
  lcd.print("  Distance    ");
  lcd.setCursor(0,1);
  lcd.print("  Measurement  ");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("    Made By    ");
  lcd.setCursor(0,1);
  lcd.print("    HASH    ");
  delay(2000);
  lcd.clear();
}

/*==============================================================================
 * LOOP()
 *============================================================================*/
void loop() 
{
  byte pin, analogPin;
  /* DIGITALREAD - as fast as possible, check for changes and output them to the
   * FTDI buffer using Serial.print()  */
  checkDigitalInputs();  
  /* SERIALREAD - processing incoming messagse as soon as possible, while still
   * checking digital inputs.  */
  while(Firmata.available())
    Firmata.processInput();
  /* SEND FTDI WRITE BUFFER - make sure that the FTDI buffer doesn't go over
   * 60 bytes. use a timer to sending an event character every 4 ms to
   * trigger the buffer to dump. */
  currentMillis = millis();
  if (currentMillis - previousMillis > samplingInterval) {
    previousMillis += samplingInterval;
    /* ANALOGREAD - do all analogReads() at the configured sampling interval */
    for(pin=0; pin<TOTAL_PINS; pin++) {
      if (IS_PIN_ANALOG(pin) && pinConfig[pin] == ANALOG) {
        analogPin = PIN_TO_ANALOG(pin);
        if (analogInputsToReport & (1 << analogPin)) {
          Firmata.sendAnalog(analogPin, analogRead(analogPin));
        }
      }
    }
    // report i2c data for all device with read continuous mode enabled
    if (queryIndex > -1) {
      for (byte i = 0; i < queryIndex + 1; i++) {
        readAndReportData(query[i].addr, query[i].reg, query[i].bytes);
      }
    }
  }
  /*Distance measurement with Ultrasonic Sensor */
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distanceCm= duration*0.034/2;                                                                                 
  lcd.setCursor(0,0);                                                 
  lcd.print("Distance Measur.");
  delay(10);
  lcd.setCursor(0,1);
  lcd.print("Distance:");
  lcd.print(distanceCm);
  lcd.print(" Cm ");
  Serial.print(distanceCm);
  delay(10);

}

1. 您还可以在链接2中看到Firmata.h和Firmata.cpp文件。打开记事本复制粘贴他们的代码使你的桌面上有两个同名文件。去你安装arduino的地方。查找firmata文件夹并在其中查看两个文件，然后用这些新文件替换旧文件。 完成50%

2. 打开链接#1，您将看到pyFirmata.py和util.py文件，其中添加了PULSE#u IN功能。绿色区域是代码中所做的添加。有关更多选项，请参见左侧的三点按钮选择查看文件

3. 打开Python IDE，打开pyfirmata.py和util.py，并用新代码替换它。保存

现在，我们已经在Python和Arduino AVR平台中添加了PULSE_的代码。参见链接#1中的示例，以在函数中使用脉冲。享受

另外，我没有添加test.py文件，找不到要添加的位置和要替换的文件。如果您有错误，请尝试添加该错误。如果你发现什么，请发邮件