CPU load during HTTP response can get sockets stuck

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dave_irvine

Oh Gordon you genius!

Flow control works, you just have to reconfigure the UART to enable it.

AT+UART=<baudrate>,<databits>,<stopbits>,<parity>,<flow control>

: flow control
‣ 0: flow control is not enabled
‣ 1: enable RTS
‣ 2: enable CTS
‣ 3: enable both RTS and CTS

not sure what RTS is, but CTS works fine.

Also, looks like we now have the baud range that ESP8266 supports:

The range of baud rates supported: 110~115200*40.

From my reading I think the *40 has something to do with the clock speed of the serial line?

Because 115200*40 is 4608000, and that is the baud rate I set that got me into my very nasty mess of needing to reflash the ESP8266. I'm guessing the Espruino just can't go that high.

var wifi = require("EspruinoWiFi");
var http = require('http');
var indexOK = "<html><head><link rel='stylesheet' href='1'><link rel='stylesheet' href='2'></head><body>OK!</body></html>";
var indexBAD = "<html><head><link rel='stylesheet' href='1'><link rel='stylesheet' href='2'><link rel='stylesheet' href='3'></head><body>NOT OK!</body></html>";
var indexVERYBAD = "<html><head><link rel='stylesheet' href='1'><link rel='stylesheet' href='2'><link rel='stylesheet' href='3'><link rel='stylesheet' href='4'></head><body>NOT OK!</body></html>";

function generateJunk(length) {
  var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

  for(var i = 0; i < length; i++) {
    text += possible.charAt(Math.floor(Math.random() * possible.length));
  }

  return text;
}

function handleHTTPRequest(req, res) {
  //Flow control close
  digitalWrite(A15,1);
  switch (req.url) {
      case '/':
        res.writeHead(200, {
          "Content-Type": "text/html",
        });
//        res.end(indexOK);
        res.end(indexVERYBAD);
        break;
      default:
      // Generate some CPU load
      
        var junk = generateJunk(1024);
        //console.log(process.memory());
        res.writeHead(200, {
          "Content-Type": "text/css",
        });
        res.end(junk);
    }
  //flow control open
  digitalWrite(A15,0);
}


wifi.startAP('test', {
  password: 'mytestap123',
  authMode: 'wpa2',
}, function(err) {
  if (err) { throw err; }

  var at = wifi.at;

  at.cmd('AT+UART_CUR=115200,8,1,0,2\r\n', 10000, function (data) {
    if (data === 'OK') {
      // Flow control open
      digitalWrite(A15,0);
      // Reconfigure serial 
      Serial2.setup(115200, { rx: A3, tx : A2 });

      //Flush anything in at's buffer
      at.cmd('AT\r\n', 1000, function(data) {
        console.log(data);
        console.log('http server started');
        http.createServer(handleHTTPRequest).listen(80);
      });
    }
  });
});

CPU load during HTTP response can get sockets stuck

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