Key Event Listener not working through Epic USB port


I’m using sammachin’s elegant setup to detect key presses on a Groov Epic PR1 : KeyPressEventInDashboard

It works perfectly once deployed on the Epic and viewed from my desktop. But it will not work with a keyboard directly hooked up to the onboard USB ports. The keyboard only seems to be read when a text input box is triggered.

There seems to be something in the design of the Epic that I’m not privy to. Any thoughts?

Hi Ya Valerie, welcome to the forums.

You have really got an amazingly interesting first post here!

What are you trying to do? I really need to take a step back here and try and understand what problem you are trying to solve because a USB keyboard in EPIC has ‘just worked’ in most things we have done here at Opto and for most of our customers.

Thanks for the speedy reply!

Alright, I have a barcode scanner that exchanges packets as a USB HID keyboard. I need the event listener to continually monitor for keystroke changes to accept the scan. It works great when it’s hooked up through my desktop. The scanner also outputs the proper characters while plugged into the Epic once the virtual keyboard is initiated; just as any standard keyboard.

However, if no prompt is open, the input keystrokes seem to be used for navigation instead of calling the desired function.

Hope that makes sense.

Ok, so you are looking to do all the HID stuff in the background in Node-RED.
ie, you don’t want any of the barcode data to show up in any other application?

Yes, nothing fancy.

I’m open to a different approach instead of going through hoops to make this one work. I get the sense it was designed like that for a reason.

Hi Val,
I have done this in the past by using a USB to Ethernet converter for my bar code scanner. Then I bring it into Node-Red via UDP.
MorphStick Ethernet adapter - keyboard, serial, RS232, sensor
It has worked reliably for a couple of years. It is my recolection that the usb port on an epic is for mouse navigation of the groov view screens. I am not sure it is available as a native keyboard input without bringing the data in via a Node.


Here is a post from @torchard a while back that undersocres the USB port not being nativly exposed to Node-Red. In sammachin’s flow he is using the input node from the dashboard. That is not the same device (scope) as the USB port on the Epic.


Thank you so much for your reply. That makes a lot of sense. In the interest of time I think I am going to have to go with your adapter suggestion.

Thanks again!

Your welcome.
You may want the “Host” version if you are not going to have a PC involved.

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