DHT11 / clearWatch error weird behavior

If it is the DHT11 then it seems weird that it works once clearWatch() causes error. Also if I copy in the DHT11 code (slightly modified so it runs) then it consistently gets correct data from the start. So I doubt it is the DHT11 hardware. (Though now it crashes later on due to "New interpreter error: MEMORY")

var ht={pin: D27};

function DHT11read(cb, n) {
  if (!n) n=10;
  var d = "";
//  var ht = this;
  digitalWrite(ht.pin, 0);
  pinMode(ht.pin,"output"); // force pin state to output
  // start watching for state change
  this.watch = setWatch(function(t) {
    d+=0|(t.time-t.lastTime>0.00005);
  }, ht.pin, {edge:'falling',repeat:true} );
  // raise pulse after 1ms
  setTimeout(function() {pinMode(ht.pin,'input_pullup');pinMode(ht.pin);},20);
  // stop looking after 50ms
  setTimeout(function() {
    if(ht.watch){ ht.watch = clearWatch(ht.watch); }
    var cks =
        parseInt(d.substr(2,8),2)+
        parseInt(d.substr(10,8),2)+
        parseInt(d.substr(18,8),2)+
        parseInt(d.substr(26,8),2);
    if (cks&&((cks&0xFF)==parseInt(d.substr(34,8),2))) {
      cb({
        raw : d,
        rh : parseInt(d.substr(2,8),2),
        temp : parseInt(d.substr(18,8),2)
      });
    } else {
      //if (n>1) setTimeout(function() {ht.read(cb,--n);},500);
      if (n>1) setTimeout(function() {DHT11read(cb,--n);},500);
      else cb({err:true, checksumError:cks>0, raw:d, temp:-1, rh:-1});
    }
  }, 50);
}

var displayReady=false;
//var dht = require("DHT11").connect(D27);

var spi = new SPI();
spi.setup({mosi:D23 /* sda */, sck:D22 /* scl */});
var g = require("ILI9163").connect(spi, D21 /* DC */, D18 /* CE */, D19 /* RST */, function() { 
  displayReady = true; });
require("Font8x12").add(Graphics);

var temp = "N/A";
var rh = "N/A";

function updateDisplay() {
  return;
  if (!displayReady)
    return;
    console.log("ILI9163");
    g.clear();
    g.setColor(1,1,1);
    //g.setFont8x12();
    g.setFontVector(8);
    g.setRotation(1);
    g.drawString("Mensa Norge Landstreff FTW!",0,0);
    
    g.setFontVector(20);
  
    g.setColor(1,0.5,1);
    g.drawString("Temp: " + temp.toString(),0,10);
    
    g.setColor(0,1,1);
    g.drawString("Humid: " + rh.toString(),0,40);
     
}

function readSensor() {
    console.log("DHT11 pre read");
  //dht.read(
  DHT11read(
    function (a) {
    console.log("DHT11 post read");
    temp = a.temp;
    rh = a.rh;
    console.log(a);
    updateDisplay();
  });
}


setInterval(function() {
  readSensor();
}, 10000);

Result:

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2v04 (c) 2019 G.Williams
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DHT11 pre read
DHT11 post read
{
"raw": "010011001000000000000110000000010001001110",
"rh": 50, "temp": 24 }
DHT11 pre read
DHT11 post read
{
"raw": "010011010000000000000101110000100101010100",
"rh": 52, "temp": 23 }
DHT11 pre read
DHT11 post read
{
"raw": "010011001000000000000101110000100101010010",
"rh": 50, "temp": 23 }
DHT11 pre read
DHT11 post read
{
"raw": "010011000100000000000110010000100101010011",
"rh": 49, "temp": 25 }
DHT11 pre read
DHT11 post read
{
"raw": "010011000100000000000110000000000001001001",
"rh": 49, "temp": 24 }
DHT11 pre read
DHT11 post read
{
"raw": "010011000000000000000110000000000001001000",
"rh": 48, "temp": 24 }
DHT11 pre read
DHT11 post read
{
"raw": "010011000000000000000110000000000001001000",
"rh": 48, "temp": 24 }
DHT11 pre read
DHT11 post read
{
"raw": "010011000100000000000110000000000001001001",
"rh": 49, "temp": 24 }
DHT11 pre read
DHT11 post read
{ "err": true, "checksumError": false,
"raw": "0",
"temp": -1, "rh": -1 }
DHT11 pre read
DHT11 post read
{ "err": true, "checksumError": false,
"raw": "0",
"temp": -1, "rh": -1 }
DHT11 pre read
Execution Interrupted during event processing.
New interpreter error: MEMORY
DHT11 pre read
ERROR: Ctrl-C while processing interval - removing it.
Execution Interrupted during event processing.
New interpreter error: CALLBACK