library is not working with more than 2 keyboards

[philippschwemberger]

Hi!

Thank you for this great library.
It is exactly what I need for a project where i have to listen to and be able to distinguish between 4 different keyboard inputs.

I tried it on ubuntu 16.04 and on raspberry pi 3.
Everything works fine with 2 keyboards attached, but unfortunately I get some very strange behaviour when I attach a third one.

I use this slightly modified example code inside of the example folder

const InputEvent = require('../')

let inputSlots = [21, 23]
let inputs = []
let readers = []

for (let i = 0; i < inputSlots.length; i++) {
  try {
    inputs[i] = new InputEvent(`/dev/input/event${inputSlots[i]}`)
    readers[i] = new InputEvent.Keyboard(inputs[i])
    readers[i].on('keyup', (data) => { console.log(`reader ${i}: ${data.code}`) })
  } catch (err) {
    console.error(`Can not open device ${i}`)
  }
  if (readers[i]) {
    readers[i].on('error', (data) => { console.log(`reader ${i}: ${data.code}`) }) 
  }
}

When I adapt the inputSlots array and attach a third keyboard, the keycode doesn't get logged to the console immediately when pressing a key.
I have to press a key on one of the other 2 attached keyboards, then the keycode from before and the keycode from the key that was just pressed are logged.
If i now press another key on this keyboard the thing starts again and i have to press a key on one of the other keyboards in order to log the keycode.

I am wondering if you have ever encountered this problem, or if you happen to know what could be the reason for this behaviour.

I also tried it with the 'keydown' and 'keypress' event, but that didnt change anything.

Thank you very much
Best regards

[Toudoo]

Hi !

I got the same problem. After a little search, it appears that the problem comes from the readstreams inside the index.js file.
If you press a key on keyboard 1, the .on("data") event from the readstream is emitted.
If you press it again, the event won't be emitted again until you press a key on another keyboard.

Sadly, I don't know how to fix it.

[philippschwemberger]

@Toudoo

Thank you for sharing your insights! :)

I planned to use it for with 4 RFID-readers that act like a keyboard, but in the end I had to use NFC-reader anyways.

cheers,
Philipp