PUCK Ble HID keyboard

Just got your reply...

function myCommand2() {
  setTimeout(sendLowA, 200);
  setTimeout(sendLowB, 200);
  setTimeout(sendLowC, 200);
}

So as above this has the effect of getting all 3 functions called at the same time(ish), 200ms from when myCommand2 was executed. You need either to do the nesting thing, or to set the timeouts to 200,400 and 600.