node.js - 如何将URM37（测距仪）连接到Arduino并通过nodeJS读取数据

Question

我买了这个测距仪http://www.dfrobot.com/wiki/index.php/URM37_V3.2_Ultrasonic_Sensor_(SKU:SEN0001)

现在我很难让它在 nodeJS 上运行。我的设置是使用“firmata”库的 Arduino UNO 和 nodeJs。

我尝试了什么： 1. 我用原生 Arduino IDE 测试了测距仪，它工作正常。2. 然后我从 Arduino IDE 将数据写入 EEPROM（代码示例如下）：

int cmmd1[]={
  0x44,0x00,0x10,0x54};//low byte stored in the sensor for the distance threshold.
int cmmd2[]={
  0x44,0x01,0x00,0x45};//high byte, write 0x0010 into address 0x01 and 0x00,so the threshold is set to 16cm
int cmmd3[]={
  0x44,0x02,0xaa,0xf0};// Autonomous mode. write 0xaa into address 0x02
//int cmmd3[]={
//  0x44,0x02,0xbb,0x01};  // PWM mode. write 0xbb into address 0x02
int i;

void setup(){                                 
  Serial.begin(9600);                         // Sets the baud rate to 9600
  A_Mode_Setup();                             //PWM mode setup function
}

void loop()
{
}                      

void A_Mode_Setup(){ 
  //write the data into the URM37 EEPROM
  for (i=0;i<4;i++)
    Serial.write(cmmd3[i]);                             
  delay(200);                                           

  for (i=0;i<4;i++)
    Serial.write(cmmd1[i]);
  delay(200);

  for (i=0;i<4;i++)
    Serial.write(cmmd2[i]);
  delay(200);

}

1. 我试图制作与手册中相同的代码以使其工作但在nodeJS中，但我失败了：

   var board = new firmata.Board('/dev/cu.usbmodemfd121', function() {
   
   var command = [0x44, 0x02, 0xbb, 0x01];
   
   board.pinMode(5, board.MODES.OUTPUT);
   
   board.digitalWrite(5, board.HIGH);
   
   board.pinMode(3, board.MODES.INPUT);
   
   board.sp.write(command, function(err, results) {
       console.log(arguments)
   });
   
   var callback = function() {
       console.log(arguments);
       //console.log(this)
   }
   
   board.on('pulse-in-3', callback);
   
   board.on('pin-state-3', callback);
   
   board.pulseIn({
       pin: 3,
       value: board.LOW,
       timeout: 50
   }, callback);
   
   setInterval(function() {
       board.digitalWrite(5, board.LOW);
       board.digitalWrite(5, board.HIGH);
   
   }, 100);
   

   });

请各位大侠帮帮我！