树莓派 Node-js GPIO 控制

Question

我想用按钮打开 GPIO4 上的 LED。但是没有任何反应。日志不会显示任何内容。我想我打开功能或编写功能失败了。

var http = require('http');
var Gpio = require('onoff').Gpio;

var LED = new Gpio(4, 'out');


var http = require('http');
http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.write('<button onclick="LEDon()">ON</button>');
    res.write('<button onclick="LEDoff()">OFF</button>');
    function LEDon(){
        LED.writeSync(1);
        console.log('1');
    }
    
    function LEDoff(){
        LED.writeSync(0);
        console.log('2');
    }
  res.end();
}).listen(8080);

Answer 1

您好，欢迎来到 SO，

试试这个：

var http = require('http');
var HttpDispatcher = require('httpdispatcher');
var Gpio = require('onoff').Gpio;

var dispatcher = new HttpDispatcher();

var LED = new Gpio(4, 'out');

function handleRequest(request, response){
    try {
        // log the request on console
        console.log(request.url);
        // Dispatch
        dispatcher.dispatch(request, response);
    } catch(err) {
        console.log(err);
    }
}  

dispatcher.onGet('/', function(req, res) {
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.write(`
        <form action="/on" method="post">
            <input type="submit" value="On" />
        </form>
    `);


    res.write(`
        <form action="/off" method="post">
            <input type="submit" value="Off" />
        </form>
    `);
});

dispatcher.onPost('/on', function(req, res) {
    LED.writeSync(1);
    console.log('1');
});

dispatcher.onPost('/off', function(req, res) {
    LED.writeSync(0);
    console.log('2');
});

http.createServer(handleRequest).listen(8080);

您还需要通过运行安装 httpdispatcher 软件包 npm i httpdispatcher --save

你的代码不工作的原因是因为你试图通过你的浏览器调用节点中的函数，这是不可能直接的，所以这里我们通过一些表单和 post 调用 HTTP 服务器来实现然后触发您的 GPIO 功能。

树莓派 Node-js GPIO 控制

Raspberry Node-js GPIO control

javascript

node.js

raspberry-pi

node-modules