Henex BarCode / QR Code Scanner Interface on Serial Port not working

I am trying to connect a bar code scanner to Node Red on Serial Port.
Scanner : Make: Henex, Model: HC3208R
This scanner is a wireless type. We need to use its wireless dongle at USB port and then scanner should work wireless.
Normally this scanner provide output to any text editor field like a keyboard entry. When I use it for Node Red on WINDOWS OS. I need to change the interface to "USB Virtual COM". Then It works perfectly fine via serial port. I configure the right COM Port - COM4 to which scanner is connected in node red Serial IN node.
Now when I try the same thing with Raspberry pi with Raspbian OS, this device (wireless dongle) is detected at ttyUSB0. I configure USB0 at serial IN port. Connection is successful and serial in node status is "Connected". But I don't get any input at debug when I scan any code using scanner.
I have rightly used the settings "USB Virtual COM" which works really well with windows OS.

For text editor input, it works fine with Raspberry pi also.
I need this to work with node red Serial IN on raspberry pi. Please suggest what can be wrong and how this can be solved? I tried with the manufacturer, but did not get much details.
Node Red Version: V1.3.5. Flow example is as below:

        "id": "736c7e71.a8a8",
        "type": "serial in",
        "z": "d3889328.d4132",
        "name": "",
        "serial": "85ed1317.7df08",
        "x": 330,
        "y": 160,
        "wires": [
        "id": "7ab9457.d922dbc",
        "type": "debug",
        "z": "d3889328.d4132",
        "name": "",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "false",
        "statusVal": "",
        "statusType": "auto",
        "x": 580,
        "y": 180,
        "wires": []
        "id": "85ed1317.7df08",
        "type": "serial-port",
        "serialport": "/dev/ttyUSB0",
        "serialbaud": "9600",
        "databits": "8",
        "parity": "none",
        "stopbits": "1",
        "waitfor": "",
        "dtr": "none",
        "rts": "none",
        "cts": "none",
        "dsr": "none",
        "newline": "0",
        "bin": "false",
        "out": "time",
        "addchar": "",
        "responsetimeout": "10000"

Apart from the serial port device, are the serial port settings exactly the same as the windows node-red?

Does the serial config node find your device?

Do you get anything if you set it to output "after a silence of"?

Thanks for the reply.

  1. Yes, all the settings are same. Baud rate, parity, stop bit etc.
  2. Yes, Serial config node find my device at /dev/ttyUSB0.
  3. No, I did not get any input even after using the split input to "after a silence of" - 200 ms.

from the same company - Henex, I am using another scanner model HC-666. This works very well using serial IN node. This goes to default USB Port of /dev/ttyASM0 and this one is a wired.
The scanner which is not working is a wireless scanner HC3208R. Even Henex Support engineer is clueless on this. However, if I use text input field in node red and use this HC3208R, it works alright.

Quick question have you set the user to dialout?

on the command line type groups
you should get something like this

pi adm dialout cdrom sudo audio video plugdev games users input render netdev lpadmin gpio i2c spi
if dial out is not on there you wont be able to access the ttyUSB0.
so to add you as a user
in the command line type
sudo adduser second_user dialout
where second user is your user name on the pi, which is pi by default.
Then reboot.
if you are on there then as in the picture

Spilt input on the character , put a hex value in here that you think may appear say 0x38 ( which is the number 8, just a random choice!) the serial node had me stumped for a while when i started with node red.

Thanks. I checked this. "dialout" is already there when I run command "groups". Please see below picture.

I also tried to add pi as user to dialout. It was also already there.

So, its still not working.

I also tried to split the input at "0x38". This still does not work.
Can you please suggest some other options? Thanks a lot for your support.

Hi Steve,
One question:
what is the difference between USB0 and ACM0?
I have one wired scanned and it connects at ACM0. It works very well with Serial IN node. So I am wondering if there can be tweak for this? Please suggest.

It just indicates they are different types of devices, requiring different drivers. As I understand it a ttyACM device uses a linux serial modem driver. The other uses the newer USB to serial device driver framework. In use it doesn't make any difference.

Thanks for the reply. Any further suggestions for serial port communication?

Typically, cheap USB based wireless input devices use HID for communicating to computer.

Have you tried getting input via the USB-HID node?

Alternatively, here are a few wireless scanners WITH serial connection (from the base)

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