Barcode Scanner: Connection, Data Matrix, Common Issues

The scanner beeps on every barcode, but there is silence in the software; or the "Chestny ZNAK" marking code refuses to be recognized, even though the regular item barcode is read without any problems. In both cases, the issue is almost never a broken scanner, but rather the data transmission mode or the settings for a specific code type. Let's walk through the diagnostics step by step.

1. Symptom → Cause → Section#

2. How the Scanner Transmits Data: HID, COM, or Driver#

Three ways a scanner transmits the read code to a computer:

• HID keyboard — the most common "plug-and-play" mode: the scanner emulates a keyboard and "types" the code into the currently focused field as if it were typed manually.
• Virtual COM port — the scanner is visible to the system as a serial port; data must be fetched directly by the POS/inventory management software itself; typing "into any field" like a keyboard will not work.
• Manufacturer driver mode — data goes through an SDK/service, usually for complex scenarios (multiple scanners, software profiles).

Diagnostic test. Open Notepad, place the cursor in the field, and scan a barcode. If the code appears, the scanner and its mode (most likely HID) are working fine, and if the working software remains silent, the issue lies in its configuration (it expects a different mode or the cursor is not in the right field). If Notepad is also blank, the issue is with the scanner itself or its transmission mode (§3). The test instantly separates "the scanner is not working" from "the software is not listening to the scanner."

3. Beeps, but Nothing Enters the Software#

If the Notepad test (§2) yielded no results either, check the following:

1. Suffix after the code. In HID mode, the scanner must append an Enter character (less often Tab) after the code — otherwise, the cursor remains in the input field, and the software does not understand that the input is complete. This is enabled using a setup barcode from the model's programming sheet (usually a PDF on the manufacturer's website).
2. Keyboard layout. The scanner emulates a specific layout (usually EN-US). With an active RU layout in the system, letter characters in the code appear as gibberish, while numbers are correct. Solution: switch the system layout or reprogram the scanner for RU using the same setup barcode.
3. Software expects a different mode. Everything types normally in Notepad, but the POS software is silent — check the input mode (HID/COM) in its settings and align it with the mode the scanner actually operates in.

4. Scanner physically cannot read the code#

Before changing settings, check simple physical reading factors:

1. Code condition. Creases, scuffs, or a tear in the label on a package curve often make part of the barcode unreadable.
2. Glare. Glossy film or cellophane over the code reflects the scanner's light — tilt the package at a different angle or remove the film.
3. Scanner window. Dust, fingerprints, or scratches on the reading window reduce contrast — wipe it with a soft cloth.
4. Distance and angle. Every model has its own operating range; holding it too close or at an acute angle prevents the code from being captured properly.
5. Code type is beyond the scanner's capabilities — see §5, a separate and very common cause.

5. Reads EAN-13, but Not Data Matrix: 1D vs. 2D#

This is not a malfunction, but a physical limitation of the technology: a 1D (laser) scanner reads only linear barcodes (EAN-13, EAN-8, Code128) — it literally scans a single line with a laser and cannot interpret a two-dimensional pattern. A 2D imager takes a picture of the code with a camera and reads both linear and 2D codes — QR, Data Matrix, including "Chestny ZNAK" labeling codes.

How to identify your model: check the data sheet on the manufacturer's website ("laser"/"1D" or "imager"/"2D") or simply scan any QR code — a 1D scanner will not react to it at all. If 2D is required for labeling and your scanner is 1D, this cannot be configured; you need to replace it with a 2D model.

6. 2D Scanner Configuration for "Chestny ZNAK"#

The marking code is a GS1 DataMatrix: several variable-length fields (product code, serial number, crypto tail) without space separators, replaced instead by a control group separator character (GS, also known as FNC1). If the scanner transmits the code "raw" without this character, the fields merge into a single string, and the POS cannot parse the code—even if the barcode itself was read perfectly.

Typical configuration (menu items vary based on vendor instructions for your model, usually a programming sheet or configuration utility):

1. Enable GS1 DataMatrix symbology recognition (sometimes "AIM Identifiers"—a prefix with code type and version).
2. Enable control character transmission (GS/FNC1) in the output string—without this step, marking code parsing will fail.
3. Save the profile using the "Save settings" barcode from the same sheet.
4. Test with a demo marking code (not on a real product)—ensure that the software receives a full string with readable fields, rather than a merged set of digits.

7. Connecting to a Smart Terminal and Factory Reset#

Smart terminal (Android). Make sure the terminal supports USB-OTG (host mode — not every model enables this out of the box). Connect the scanner via an OTG cable in HID keyboard mode — this is the most compatible option without needing the manufacturer's SDK. Some scanners cannot be fully powered by the terminal via OTG: if it doesn't turn on or blinks unstably, you will need a cable with an external power supply or a scanner with its own battery. Test using the same method described in §2.

Resetting and configuring from scratch. Look for the programming sheet (a set of service barcodes for configuration without a PC) on the manufacturer's website by exact model, usually under the "support"/"documentation" section. Typical order for an unfamiliar or problematic scanner:

1. Factory Reset — service reset barcode from the programming sheet.
2. Base transmission profile — HID keyboard (or COM if required by the POS software, see §2).
3. Enter suffix after each code — a separate service barcode (§3).
4. GS1 DataMatrix + GS/FNC1 transmission — if you plan to scan serialization codes (§6).

Scan the codes strictly in the order given on the sheet — some models require a service "Save" code between steps, skipping which rolls back the settings.

8. Example#

A store with marked goods switched receiving to a new out-of-the-box 2D scanner. Regular packaging barcodes were read perfectly, but the POS system did not accept marking codes — it couldn't find the item on the receipt. Checking the programming sheet showed that the default profile did not include GS separator transmission. After completing the steps from §6 (GS1 DataMatrix + control characters + verification on a test code), marked goods started scanning normally.

9. How to do this in Cenaly#

• The scanner connects via Cenaly Hardware Bridge; its status is visible in the Hardware section, and "Hardware checks" provide a quick scan test without a real item — making it convenient to verify the setup from §6 or §7 immediately after changing the profile.
• In Cenaly POS, barcode scanning is used to search for items in the catalog — simply specify the barcode in the item card.

10. Frequently Asked Questions#

Why does the code print in Notepad, but not in the POS software? The scanner and transmission mode are working fine — the issue is in the software settings: it either expects a different mode (COM instead of HID), or the cursor was not in the correct input field.

Is it mandatory to buy a 2D scanner if I don't work with product marking? No, a 1D scanner is enough for standard EAN-13/Code128 barcodes — it is cheaper. A 2D scanner is needed only for Data Matrix (marking, QR codes).

The scanner is configured for "Chestny ZNAK", but the code sometimes fails verification — is this also a scanner setting issue? Not necessarily: if the code is scanned and transmitted completely (check on the demo code from §6), and the POS still throws an error — the reason is no longer the scanner, but the marking verification itself, see about marking.

Related articles: marking at the POS · Cenaly Hardware Bridge · how to choose a POS

The material is for reference purposes only and does not replace consultation with a service center or equipment manufacturer. Primary sources: technical documentation and programming sheets from barcode scanner manufacturers, GS1 DataMatrix standard, guidelines for product marking (chestnyznak.rf).