Windows App · Support Docs

Swift Interface

The bridge between your Swift POS and your payment terminals, printers, and cash drawers — runs quietly in the background so every transaction just works.

~11 MB Windows 10 or later Released Mar 18, 2026 .NET Framework 4.8

Download Latest

v0.1.3 · ~11 MB
Windows 10 or later

What is Swift Interface?

A lightweight Windows app connecting your salon hardware to Swift POS.

Payment Terminals

Routes payments from POS to terminal and returns results automatically.

Clover MiniClover Flex Clover CompactPAX S300PAX Aries8

Receipt Printing

Prints to network or USB printers. Supports Star Micronics and ESC/POS.

NetworkUSBStar Micronics

Cash Drawer

Auto-opens drawer via RJ-12 cable through the receipt printer on cash payments.

How it works

SI runs in your system tray. When a customer pays, Swift POS sends the charge to SI, which forwards it to the Clover or PAX terminal. The customer taps or inserts their card, and the result returns to POS in seconds. Printing works the same way: POS tells SI what to print, SI routes it to your receipt printer.

What's New

Recent updates and improvements to Swift Interface.

v0.1.3

Mar 18, 2026

Latest

Payment speed 3–7s faster — Removed 4 unnecessary delays before card processing starts

Reuse SignalR connection — POS browser no longer creates a new connection per payment (saved 200–1500ms)

Removed pre-check delay — Stopped asking terminal "already paid?" before every sale (saved 500–5000ms)

Non-blocking logging — Payment log writes no longer delay the transaction

Removed unnecessary cancel command — Stopped sending ESC to terminal before every payment

PAX: Fixed socket leak — Terminals properly disconnected after each transaction

PAX: Fixed USB timeout — Increased from 500ms to 30 seconds

PAX: Real error messages — Shows actual error instead of generic "Connection Unstable"

Clover: Fixed device name — Shows "Compact" instead of SDK class name

v0.1.0

Mar 17, 2026

Improved connection stability — Clover auto-reconnects if disconnected

Clover Compact terminal support (SDK v5.0.1)

Clover crash protection — device disconnect, null results, pre-check failures

Detailed activity logging for easier troubleshooting

Security improvements for local connections

Dec 15

Dec 15, 2025

Production build (12.15)

Clover SDK updates

Nov 30

Nov 30, 2025

Production build (26.11)

Bug fixes and stability improvements

Nov 24

Nov 24, 2025

Production build (24.11)

Nov 21

Nov 21, 2025

Initial production release

All Versions

Download any previous release of Swift Interface.

Version	Date	Notes
v0.1.3 Latest	Mar 18, 2026	Payment speed optimization + PAX socket fix
v0.1.2	Mar 18, 2026	PAX socket fix, USB timeout fix, Clover device name fix
v0.1.0	Mar 17, 2026	Clover SDK v5.0.1, crash fixes, structured logging
Dec 15	Dec 15, 2025	Production build (12.15)
Nov 30	Nov 30, 2025	Production build (26.11)
Nov 24	Nov 24, 2025	Production build (24.11)
Nov 21	Nov 21, 2025	Initial release

Rollback Instructions

Close Swift Interface on the salon PC (check the system tray).
Download the older version from the table above.
Extract and replace all files in your SI folder.
Restart Swift Interface.
Verify the connection status shows green in the POS.

Clover USB Drivers

Required for USB connection to Clover terminals. Install once per PC.

Version	Date	Supports
v5.0.1 Latest	Mar 12, 2026	Mini, Flex, Compact, Companion
v5.0.0	Jan 8, 2026	Mini, Flex, Compact, Companion
v4.0.6	Jul 8, 2022	Mini, Flex only

Clover Compact users: You must use driver v5.0.0 or newer. Older drivers do not recognize the Compact.

Full Clover USB Setup Guide →

Setup Guide

Get Swift Interface running in a few minutes.

Download & Extract

Download the ZIP file using the button above. Extract all files to a folder on your PC (e.g., C:\SwiftInterface\).

Run Swift Interface

Double-click SwiftInterface.exe to launch. Windows may show a SmartScreen warning on first run.

SmartScreen warning: Click "More info" then "Run anyway". This is normal for newly downloaded applications.

Configure Terminal in POS

In your Swift POS browser, go to Settings → Terminal and select your terminal type (Clover or PAX). Your Swift POS representative will help with the initial setup.

Pair Clover Terminal

All Clover devices (Mini, Flex, Compact) use the same setup process.

USB Connection (recommended)

Install Clover USB Drivers on your PC (download above)
On the Clover device, open the USB Pay Display app from the App Market
Connect the USB-C cable from the Clover to your PC
In Swift POS → Settings → Terminal → Add Terminal
Select Terminal Type: Clover, Protocol: USB
Click Connect — SI auto-discovers the device, no pairing code needed

Network Connection (TCP/IP)

On the Clover device, open Secure Network Pay Display from the App Market
Note the IP address shown on the Clover screen
In Swift POS → Settings → Terminal → Add Terminal
Select Terminal Type: Clover, Protocol: TCP/IP
Enter the Clover IP address and click Connect
Enter the pairing code shown on the Clover screen

View full Clover USB setup guide with screenshots →

Pair PAX Terminal

For PAX S300 or Aries8 terminals:

On the PAX terminal, go to Settings → Communication → LAN
Note the IP address and port (default: 10009)
Make sure the PAX and your PC are on the same network
In Swift POS → Settings → Terminal → Add Terminal
Select Terminal Type: PAX, enter the IP and port
Click Connect

Connect Printer

In your Swift POS, go to Settings → Printer and enter the printer IP address and port. Use the test print button to verify the connection.

Verify Connection

Open your POS in the browser. The connection indicator should show green. Run a small test payment ($0.01) to confirm the full flow — sale, tip, signature, and receipt printing. Void the test payment immediately so it doesn't process.

Troubleshooting

Common issues and how to fix them.

Check Windows Event Viewer for errors (Windows Logs → Application).
Make sure .NET Framework 4.8 is installed.
Try running as Administrator (right-click → Run as administrator).
Check if another instance is already running — look for the SI icon in the system tray.

Make sure Swift Interface is running (check the system tray icon).
Verify SI and the POS browser are on the same computer.
Check if port 3179 is blocked by Windows Firewall.
Restart Swift Interface and refresh the POS page.

USB: Try a different USB port. Check Device Manager for the Clover device.
Network: Verify the Clover terminal and PC are on the same network.
Make sure the Clover terminal is powered on and showing its home screen.
Restart both Swift Interface and the Clover terminal.

Verify the PAX IP address and port are correct in SI settings (default port: 10009).
Make sure the PAX terminal and the PC are on the same local network.
On the PAX terminal, go to Settings → Communication → LAN and confirm the IP address.
Check that no firewall is blocking the PAX port on the PC.
Restart both Swift Interface and the PAX terminal.

PAX uses TCP communication — network latency or drops will cause timeouts.
Check that the PAX terminal is not stuck on a previous transaction screen.
Cancel any pending transaction on the PAX terminal itself, then retry from POS.
If timeouts happen frequently, check the network cable/Wi-Fi signal to the PAX device.
Check SI logs at C:\Swift\Terminal\ for PAX-specific error codes.

Check SI logs at C:\Swift\Terminal\ for errors.
Try canceling the payment and re-running it.
If stuck for more than 2 minutes, restart Swift Interface.
Check the terminal screen for any prompts that need attention.
Clover: Make sure the terminal shows its home screen (not stuck on a previous prompt).
PAX: Check if the terminal is displaying a "Processing" or error screen — cancel on the terminal first.

Verify the printer IP address and port in SI settings.
Check the printer is powered on and connected to the network.
Use the test print button in SI settings to diagnose.
Cash drawer: Make sure the RJ-12 cable connects the drawer to the printer (not directly to the PC).

Check the internet connection on the salon PC.
SI checks for updates every 60 minutes — wait or restart SI to trigger an immediate check.
Check C:\Swift\Setting\SettingModel.txt — AutoUpdate should be set to True.
Manual update: Download the latest version from this page and replace the files in C:\SwiftInterface\.

Logs are located at C:\Swift\Terminal\
Log files are named by date (e.g., Action_03172026.txt, Payment_03172026.txt).
Open with any text editor (Notepad works fine).
Look for entries with Error or Exception.

System Requirements

Make sure your setup meets these requirements before installing.

Operating System

Windows 10 or later (64-bit)

Runtime

.NET Framework 4.8

Memory

8 GB RAM minimum

Disk Space

200 MB available

USB Port

For Clover USB connection

Network

For Clover network, PAX & printer

Firewall Port

3179 must be open

USB Setup Guide

Clover Compact USB Setup

Connect your Clover Compact to Swift POS in about 15 minutes. Follow each step in order.

💳

Clover Compact

Activated with your merchant account

🔌

USB-C Cable

USB-C to USB-A (included with Compact)

💻

Windows 10+ PC

Running Swift Interface

🌐

Internet

On the Compact for initial app install

Part 1 Install USB Drivers on Your PC

Install USB Drivers on Your PC

You only need to do this once per PC.

Download Clover USB Drivers

On your PC, open Chrome and go to the Downloads section
Under Clover USB Drivers, download version v5.0.1 (latest)
Extract the ZIP file to a folder on your PC

Clover Compact users: You must use driver v5.0.0 or newer. Older drivers do not recognize the Compact.

Install the Drivers

Double-click CloverUSBDrivers.exe
If Windows shows a security warning, click "Yes" or "Run anyway"
Follow the installer — click Next → Install → Finish
Restart your PC after installation

Why is this needed? Without Clover USB drivers, Windows won't recognize the Compact when you plug it in.

Part 2 Set Up the Clover Compact

Set Up the Clover Compact

You only need to do this once per Compact device.

Make Sure Your Compact Is Activated

Your Compact should already be set up with your Clover merchant account
The home screen should show your business name and Clover apps
If the Compact hasn't been set up yet, contact your Clover representative first

Install the USB Pay Display App

On the Compact, tap the Clover App Market icon (shopping bag icon)
Search for "USB Pay Display"
Tap Install and wait for it to complete

Don't see "USB Pay Display"? Contact your Clover reseller — they may need to enable semi-integration permissions on your merchant account.

Open USB Pay Display

From the Compact home screen, tap USB Pay Display
The screen will show: "Waiting for POS connection..."
Leave this app open — do not exit it

Remember: USB Pay Display must be open on the Compact whenever you want to process payments. If you close it, just reopen it from the home screen.

Part 3 Connect the Cable

Connect the Cable

Plug in the USB cable between your Compact and PC.

Plug In the USB Cable

Plug the USB-C end into the port on the back of the Compact
Plug the USB-A end into a USB port on your PC
You may hear the Windows "device connected" sound

Verify Windows Recognizes the Compact

Right-click the Start button → click Device Manager
Look for the device under "Universal Serial Bus devices" or "Clover"
No yellow warning triangle = you're good!

See "Unknown Device"? Reinstall the USB drivers from Part 1 and try a different USB port.

Part 4 Connect Swift Interface

Connect Swift Interface

Link your Swift POS to the Compact through Swift Interface.

Start Swift Interface

Open SwiftInterface.exe on your PC
The SI icon should appear in the system tray near the clock
Keep SI running — it must be open to process payments

Configure the Terminal in Swift POS

Open Swift POS in Chrome on the same PC and log in
Go to Settings → Terminal → Add Terminal
Fill in the settings:

Setting	Value
Terminal Type	`Clover`
Terminal Name	e.g., `Front Desk Compact`
Protocol Type	`USB`
Tip Type	`On Pos` or `On Terminal`

Click Save.

Connect to the Compact

Click the Connect button next to your terminal
Wait a few seconds — SI will auto-discover the Compact on USB
The Compact screen changes to show "Connected"
In Swift POS, the terminal status should show green

No pairing code needed! USB authenticates automatically through the cable.

Part 5 Test Your Setup

Test Your Setup

Run a quick test payment to confirm everything works.

Run a Test Payment

In Swift POS, create a ticket with a small amount (e.g., $0.01)
Click Pay Bill → Credit
The Compact should prompt the customer to tap/insert/swipe
Complete the payment — POS should show "Payment Approved"
Void the test payment immediately so it doesn't process

Verify the Connection Indicator

In Swift POS, check the terminal connection indicator
It should show green — ready to accept payments

All done! Your Clover Compact is connected to Swift POS via USB.

Daily Use

Each day before you start accepting payments:

Turn on Compact

Power on device

→

Open USB Pay Display

On the Compact

→

Run Swift Interface

On the PC

→

Check Green Indicator

In Swift POS

Swift POS → Swift Interface → Compact → Customer taps card → Result back to POS

Troubleshooting

Common issues and how to fix them.

Is Swift Interface running? Check the system tray
Is USB Pay Display open on the Compact?
Is the USB cable firmly plugged in on both ends?
Try: Close SI → unplug cable → replug cable → reopen SI

Check the Compact screen — may be waiting for the customer to tap/insert card
Cancel on the Compact first, then retry from POS
If stuck more than 2 minutes, restart Swift Interface

Reinstall Clover USB Drivers (Part 1 above)
Try a different USB port or a different USB cable
Restart the PC after driver installation

Contact your Clover reseller and ask them to enable semi-integration
Alternative: Use network (TCP/IP) connection instead

Check SI logs at C:\Swift\Terminal\ — open the latest Payment_*.txt
Common causes: expired card, insufficient funds, network issue on Compact

Quick Reference

Keep this handy for your front desk staff.

Cable	USB-C (Compact) to USB-A (PC)
Compact App	USB Pay Display (must be open)
PC Software	SwiftInterface.exe (must be running)
POS Setting	Terminal Type: Clover, Protocol: USB
Drivers	CloverUSBDrivers v5.0.0 or newer
Pairing Code	Not needed for USB
Port	localhost:3179 (automatic)