[Python] Datalogic GD4400 Scanner Outputs Encoded Data via CH340 Serial Interface

Problem Description I have a Datalogic GD4400 barcode scanner connected to a Raspberry Pi/Linux system via a CH340 USB-to-Serial adapter. When scanning barcodes, the scanner outputs encoded data instead of plain ASCII text.

Hardware Setup Datalogic GD4400 barcode scanner CH340 breakout board Connection: PIN 6 (TX) → CH340 RX, PIN 5 (RX) → CH340 TX, PIN 4 (GND) → CH340 GND, PIN 7 (VCC) → 5V

What I'm Seeing When I scan a barcode with text "X0043FEWFX", I get this binary output instead of plain text:

Received data (length: 11 bytes):
HEX: EA F6 76 96 36 D5 45 CD 3D 95 00


My Python code:

import serial
import time
import sys

def listen_to_scanner(device_path="/dev/ttyUSB0", baud_rate=9600):
try:
with serial.Serial(
port=device_path,
baudrate=baud_rate,
bytesize=serial.EIGHTBITS,
parity=serial.PARITY_NONE,
stopbits=serial.STOPBITS_ONE,
timeout=0.1,
rtscts=True
) as ser:
print(f"Connected to {device_path} at {baud_rate} baud")
print("Listening for scanner data... (Press Ctrl+C to stop)")

while True:
try:
data = ser.read(64)
if len(data) > 0:
print(f"\nReceived data (length: {len(data)} bytes):")
print(f"HEX: {' '.join([f'{b:02X}' for b in data])}")
try:
ascii_str = data.decode('ascii')
print(f"ASCII: {ascii_str}")
except UnicodeDecodeError:
print("*** Non-ASCII data received ***")
except serial.SerialException as e:
print(f"Serial error: {e}")
break
time.sleep(0.01)
except serial.SerialException as e:
print(f"Error with serial port: {e}")
except KeyboardInterrupt:
print("\nProgram terminated by user")

def main():
listen_to_scanner()

if __name__ == "__main__":
main()


What I've Tried

Changed Interface Settings: I've tried configuring the scanner to use "RS-232 Standard" interface using programming barcodes from the manual.

USB Mode Works: When I connect the scanner directly via USB and configure it for USB HID (keyboard) mode, it correctly outputs plain ASCII, but I need it to work with the CH340 serial connection.

Baud Rate: I've verified the baud rate is correctly set to 9600.

Physical Connections: I've verified all pins are correctly connected.

Could you please help me where i am doing wrong ? Do i need a specific decoding code for the scanner brand ?

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