Setting Up a USB QR Scanner for Your Business

What Is a USB QR Scanner?

A USB QR scanner is a small hardware device that reads QR codes and sends the result to your computer. Think of it like a keyboard that types at superhuman speed -- when you scan a QR code, the device instantly "types" the code's content and presses Enter.

This is called keyboard wedge or HID keyboard emulation. It is the industry-standard way that barcode and QR scanners communicate with computers, used by every major point-of-sale system.

The key benefits for your business:

• Plug and play -- no drivers, no software, no configuration. Plug it in and it works
• Works with any browser -- Chrome, Safari, Firefox, Edge. No extensions or apps needed
• Fast and reliable -- scans are near-instant, much faster than pointing a phone camera
• Hands-free options available -- countertop scanners let customers hold up their own phone
• Works on every admin page -- you do not need to navigate to a special scanner screen

Setting Up Your Scanner

Getting started with a USB scanner takes about 30 seconds:

1. Plug the scanner into any USB port on your computer (or connect via Bluetooth if your scanner supports it)
2. Open your browser and log in to the Carthy admin dashboard
3. That's it -- the scanner is ready to use immediately

No drivers, no software installation, no pairing process. Your computer recognises the scanner as a keyboard automatically.

Verifying the Scanner Is Active

To confirm your scanner is working with Carthy:

1. Navigate to the Scanner page in the admin sidebar
2. Look for the green "Active" indicator -- this means Carthy is listening for scanner input
3. Try scanning any QR code to test the connection

The green indicator appears on the Scanner page whenever the USB scanner detection is running. It is active on every admin page, but the visual indicator is only shown on the Scanner page.

Scanning a Customer

When a returning customer wants to record their visit, the process is seamless:

1. The customer shows their loyalty QR code on their phone (from their welcome email or saved screenshot)
2. Point the scanner at the customer's phone screen -- or if you have a hands-free scanner, the customer holds their phone in front of it
3. The scanner reads the code instantly and Carthy automatically opens the customer's profile
4. You see the customer's name, visit history, and promotion progress
5. Select the service and record the visit as usual

The entire scan-to-profile lookup takes less than a second. There is no need to navigate to a specific page first -- the scanner works from any admin page, whether you are on the Dashboard, Customers list, Promotions, or Settings.

Recommended Hardware

Any USB QR scanner that uses HID keyboard emulation will work with Carthy -- and that covers virtually every scanner on the market. Here are our tested recommendations:

Budget Options

Mid-Range Options

Professional Options

Which One Should You Choose?

For most small businesses, we recommend the Symcode MJ-3310 hands-free scanner (around EUR 50--80). It sits on your counter, and customers simply hold up their phone to have their code scanned -- no button pressing needed. This gives the fastest workflow and the best customer experience.

On a tighter budget, the Tera HW0002 (around EUR 25--35) is a great handheld option. Staff just point it at the customer's phone and pull the trigger.

Scanner Configuration Tips

Most scanners work perfectly out of the box. However, these optional tweaks can improve the experience:

Ensure the Enter Terminator Is Enabled

Carthy expects the scanner to send an Enter key (also called CR or Carriage Return) after each scan. This is the factory default on virtually all scanners, so you should not need to change anything. If scans are not being detected, check your scanner's manual for the "terminator" or "suffix" setting and make sure it is set to Enter/CR.

Enable Only QR Code Symbology

By default, most scanners are configured to read many types of codes -- barcodes, QR codes, Data Matrix, and more. For the best performance, disable all symbologies except QR Code. This speeds up scanning and prevents the scanner from accidentally reading product barcodes or other codes in view.

Your scanner's manual will have setup barcodes you can scan to enable or disable specific symbologies.

Set a Same-Code Delay

Configure your scanner to wait 3--5 seconds before it will read the same code again. This prevents accidental double-scans when a customer's phone is still in view. Look for a "same code delay" or "reread delay" setting in your scanner's manual.

Keep the Beep Enabled

Most scanners beep when they successfully read a code. Keep this enabled -- it provides instant audio feedback to both staff and customers that the scan was successful.

Testing Without a Scanner

You do not need a physical scanner to try out the USB scanning feature. The Scanner page in the admin dashboard includes a built-in Test Scanner tool.

1. Navigate to Scanner in the admin sidebar
2. Find the Test Scanner section on the page
3. Enter a customer code or paste a customer's QR code URL
4. Click "Simulate Scan"
5. The system processes the code exactly as if a real USB scanner had read it

This is useful for verifying that scanning works correctly before purchasing hardware, or for training new staff on the scanning workflow.

Troubleshooting

USB scanners are generally very reliable, but here are solutions to the most common issues:

Scanner Reads the Code but Nothing Happens

• Make sure you are logged in to the Carthy admin dashboard
• Check that the browser tab with the admin dashboard is in focus (click on it)
• Verify the scanner's Enter terminator is enabled (see Configuration Tips above)
• Try the Test Scanner tool on the Scanner page to rule out hardware issues

Characters Appear Garbled or Wrong

This is usually a keyboard layout mismatch. Most scanners assume a US English keyboard layout. If your computer is set to a different layout (e.g., German, French), special characters may be misinterpreted.

Solutions:

• Check your scanner's manual for a keyboard layout configuration barcode and scan the one matching your computer's layout
• Alternatively, temporarily switch your computer's keyboard layout to US English while using the scanner

Note: Carthy's QR codes use only standard alphanumeric characters and URL-safe symbols, so keyboard layout issues are rare in practice.

Caps Lock Causes Lookup Failures

If Caps Lock is on, the scanner may send inverted capitalisation (lowercase becomes uppercase and vice versa). Carthy handles this gracefully with case-insensitive lookups, but if you experience issues:

• Turn off Caps Lock on your keyboard
• Some scanners have a Caps Lock compensation setting -- check your scanner's manual

Same Customer Scanned Twice

Carthy includes double-scan prevention that ignores the same QR code if scanned again within a few seconds. If you are seeing duplicate scans:

• Configure a same-code delay on your scanner (see Configuration Tips)
• Move the customer's phone away from the scanner after the first successful scan
• For hands-free scanners, ask the customer to remove their phone once they hear the beep

Scanner Not Detected at All

• Try a different USB port on your computer
• Unplug the scanner, wait 5 seconds, and plug it back in
• Test the scanner in a text editor (e.g., Notepad) -- scan any QR code and check if text appears. If it does, the scanner works and the issue is with the browser or Carthy connection
• Make sure you are not using a USB hub that is underpowered -- try plugging directly into the computer

USB Scanner vs. Mobile App: When to Use Which

Carthy gives you two ways to scan customer QR codes. Here is a quick comparison to help you decide which fits your workflow:

Many businesses use both -- a USB scanner at the main counter for speed and convenience, and the mobile app for staff working away from the desk. They work with the same customer data, so you can mix and match freely.