Modules - what am I doing wrong

Sorry To keep asking,

I am seem to making some progress using a paired back node script and now rewriting in to use on the espruino, however I am stuck finding a way of making 'Buffer.from' working, Is there espruino equivalent ?

I am looking to run this line

const sounddata = Buffer.from([0x08, 0x00, 0x81, 0x01, 0x11, 0x51, 0x01, 0x05]);