Sending a buffer from momentary button action

I'm trying to send 2 different sequences of bytes using a momentary button widget in Node Red. I want to send a buffer (NOT an array) of raw bytes [145,48,64] when a button (with configurable color) is pressed, and then a different buffer [129,48,64] of raw bytes when that button (with different color) is released. I'm not a JS or HTML programmer. Just a hacker with some Node Red experience. Here is the code I'm using as a modified Template Node from someone else:

var bon = Buffer.from([145,48,64]);
var boff = Buffer.from([129,48,64]);
this.scope.on = {payload: bon}; = {payload: boff};

Ideally the code could be buried in a single Node (like the Template Node) with the buffer values embedded in that node since I'm trying to create a control panel with lots of these buttons and don't want a clogged up Node Red IDE.

I'd appreciate any help. Thanks in advance.


Buffer is a nodejs thing - not available in the browser.

You could simply send an array then using a function node at server side (in node-red) convert the array into a Buffer...

Function node

msg.payload = Buffer.from(msg.payload);
return msg;


That worked great! I was just able to “bufferize” the array generated by the Template.

Now, using the existing code as a basis, can you help me define the text color and background color? Right now the default is white text on red background.