-1
我是JavaScript的初學者，所以這可能是一個業餘的錯誤。出於某種原因，當我在js.node中運行此代碼時，我總是得到默認情況。傳入的數據顯示到控制檯很好，所以我假設變量latestData實際上存儲傳入的數據。 console.log在每種情況下都是爲了讓我知道它使用的是哪種情況（如果有的話）。JavaScript Switch Case未按預期工作
任何幫助表示讚賞！
編輯：代碼修改如下所示，但我仍然有相同的問題 我會分享arduino程序和當我回家時今天如果有幫助的串行監視器的屏幕截圖。
var arDrone = require('ar-drone'); //Include the ar-drone library
var serialport = require('node-serialport'); //Include the serialport Library
var latestData = 0;
SerialPort = serialport.SerialPort, //Create local Instance
//Define the port and function to call
myPort = new SerialPort("/dev/ttyO3", {
parser: serialport.parsers.readline("\r\n"), //Look for return and newline at the end of each packet. Serial.println() adds this
baud: 9600
});
//Define what functions are called on each event
myPort.on('data', saveLatestData);
myPort.on('close', showPortClose);
myPort.on('error', showError);
myPort.on('open', showPortOpen);
//Callback functions for serial data events
function showPortOpen() {
console.log('PORT OPEN');
}
function saveLatestData(data) {
console.log(data);
latestData = data;
}
function showPortClose() {
console.log('PORT CLOSED');
}
function showError(error) {
console.log('SERIAL PORT ERROR ' + error);
}
var client = arDrone.createClient();
//client.takeoff(); //Drone take off command, functional but removed for bench test
// Logic to read in sensor data from arduino and send flight commands to drone
switch(String.fromCharCode(latestData))
{
case 'X':
console.log('X IR');
client
.after(1000, function() {
this.clockwise(0.1);
})
.after(1000, function() {
this.front(0.05);
});
break;
case 'Y':
console.log('Y IR');
client
.after(1000, function() {
this.counterClockwise(0.1);
})
.after(1000, function() {
this.front(0.05)
});
break;
case 'Z':
console.log('Z IR');
client
.after(1000, function() {
this.back(0.05);
})
.after(1000, function() {
this.clockwise(0.1)
});
break;
case 'A':
console.log('A IR');
client
.after(1000, function() {
this.back(0.05);
})
.after(1000, function() {
this.clockwise(0.1)
});
break;
case 'N':
console.log('N IR');
client
.after(1000, function() {
this.front(0.05);
});
break;
case 'L':
console.log('L IR');
client
.after(1000, function() {
this.clockwise(0.1);
})
.after(1000, function() {
this.front(0.05);
});
break;
case 'R':
console.log('R IR');
client
.after(1000, function() {
this.counterClockwise(0.1);
})
.after(1000, function() {
this.front(0.05)
});
break;
default:
console.log('DEFAULT CASE');
client
.after(1000, function() {
this.front(0.05)
});
break;
}
以下是將串行數據發送到js.node正在讀取的端口的arduino代碼。很簡單
/*
description:
The sample code is used to measure distance by GP2Y0A02YK IR ranger sensor.
The information is then sent serially to Ar.Drone serial port tty03
VCC -- VCC
GND -- GND
Signal -- Analog 1
*/
/*int IRpinX = 1; // analog pin for reading the X IR sensor
int IRpinY = 3; // analog pin for reading the Y IR sensor
int IRpinZ = 5; // analog pin for reading the Z IR sensor
*/
bool X; // set high when X IR sensor detects obstacle
bool Y; // set high when Y IR sensor detects obstacle
bool Z; // set high when Z IR sensor detects obstacle
void setup()
{
Serial.begin(9600); // start the serial port
//SET ANALOG PINS TO BE USED FOR IR SENSOR INPUT
pinMode(A1, INPUT); // X SENSOR
pinMode(A3, INPUT); // Y SENSOR
pinMode(A5, INPUT); // Z SENSOR
}
void loop()
{
float voltsX = analogRead(A1)*0.0048828125; // value from sensor (5/1024) - if running 3.3.volts then change 5 to 3.3
float voltsY = analogRead(A3)*0.0048828125;
float voltsZ = analogRead(A5)*0.0048828125;
float distanceX = 65*pow(voltsX, -1.10); // worked out from graph 65 = theretical distance/(1/volts);
float distanceY = 65*pow(voltsY, -1.10);
float distanceZ = 65*pow(voltsZ, -1.10);
/*print the distances for each sensor to verify in the serial monitor
Used for initial testing
Serial.print("X = ");
Serial.println(voltsX);
Serial.print("Y = ");
Serial.println(voltsY);
Serial.print("Z = ");
Serial.println(voltsZ);*/
/*statements compare distance calculation to a static range and
set a bit high for each sensor that detects an obstacle
May change to compare voltage as it seemed more stable*/
if (distanceX <=100) // check for obstacle in X direction
{
X = HIGH;
}
else X = LOW;
if (distanceY <=100) // check for obstacle in Y direction
{
Y = HIGH;
}
else Y = LOW;
if (distanceZ <=100) // check for obstacle in Z direction
{
Z = HIGH;
}
else Z = LOW;
// Obstacle detected at X sensor only
if (X == HIGH && Y == LOW && Z == LOW)
{
Serial.println('X'); // Transmit character X in hex over serial port
}
// Obstacle detected at Y sensor only
if (X == LOW && Y == HIGH && Z == LOW)
{
Serial.println('Y'); // Transmit character Y in hex over serial port
}
// Obstacle detected at Z sensor only
if (X == LOW && Y == LOW && Z == HIGH)
{
Serial.println('Z'); // Transmit character Z in hex over serial port
}
// Obstacle detected at X and Y sensors only
if (X == HIGH && Y == HIGH && Z == LOW)
{
Serial.println('Z'); // Transmit character Z in hex over serial port
} // Not sure what to do in this condition. Turn instead?
// Obstacle detected at X and Z sensors only
if (X == HIGH && Y == LOW && Z == HIGH)
{
Serial.println('R'); // Transmit character R in hex over serial port
} // Rotate drone clockwise
// Obstacle detected at Y and Z sensors only
if (X == LOW && Y == HIGH && Z == HIGH)
{
Serial.println('L'); // Transmit character L in hex over serial port
} // Rotate drone counterclockwise
// Obstacle detected at X, Y and Z sensors
if (X == HIGH && Y == HIGH && Z == HIGH)
{
Serial.println('A'); // Transmit character L in hex over serial port
} // Rotate drone counterclockwise
// No Obstacle Detected
if (X == LOW && Y == LOW && Z == LOW)
{
Serial.println('N'); // Transmit character N over serial port
} // Hover in place
delay(100); // wait time in mS used to slow data send interval for testing
}
併爲每個case語句添加'break;'，否則它將會通過默認語句 – Reflective
正在接收的數據是使用serial.println（）從arduino發送的，以ASCII文本形式發送字符。這很可能是問題的一部分。謝謝！ –
'typeof latestData'會給你什麼？如果它是一個字符串，那麼你可能需要獲取第一個字符作爲字符串：'latestData [0]' –