Payment Terminal Setup

How to connect a card payment terminal to the In-Store App — overview of supported integrations and architecture.

The In-Store App does not talk directly to a card terminal. Payments go through a small bridge service that runs as a Windows service on the cashier PC alongside the terminal driver. The app sends payment requests over HTTP to the bridge, and the bridge handles the protocol-specific communication with the terminal.

┌─────────────────────────────────────────────────────────────────────────────┐
│  Cashier PC                                                                 │
│                                                                             │
│  ┌──────────────┐   HTTP (localhost)   ┌──────────────────────┐            │
│  │  In-Store    │ ─────────────────▶  │  Bridge middleware    │            │
│  │  App         │ ◀─────────────────  │  (Windows service)   │            │
│  │  (Flutter)   │   JSON response     │                      │            │
│  └──────────────┘                     └──────────┬───────────┘            │
│                                                  │                         │
│                                         protocol │ depends on              │
│                                         terminal │ type                    │
└──────────────────────────────────────────────────┼─────────────────────────┘
                                                   │
              ┌────────────────────────────────────┼──────────────────────┐
              │ Nets/Baxi                          │ Verifone             │
              │                                    │                      │
              │  XML/TCP :6000                     │  PSDK or VIM         │
              │       ▼                            │                      │
              │  [BaxiAgent]                       │  Android terminal:   │
              │  TCP :6001 or USB                  │  TCP → terminal IP   │
              │       ▼                            │                      │
              │  [Nets terminal]                   │  P400 terminal:      │
              │       ▼                            │  TCP :9600 ← terminal│
              │  TCP :9670                         │  dials in to bridge  │
              │  [Nets servers]                    └──────────────────────┘
              └────────────────────────────────────┘

Setup overview

Every integration requires the same three steps:

Step	What to do
1. OMS	Add the payment method in Omnium back office and assign it to the correct market and store
2. Bridge	Install and configure the bridge service on the cashier PC
3. POS app	Configure terminal type, bridge address, port, and payment method name in the app settings

Supported integrations

Integration	Terminal	Bridge service	Port
Nets / Baxi	Nets terminals (ethernet or USB)	`OmniumNetsBridge`	`5100`
Verifone P400 / M400	Verifone P400, M400	`OmniumVerifoneVimBridge`	`5102`
Verifone Android	Verifone Android terminals	`OmniumVerifoneBridge`	`5101`

POS app settings

In the app, go to Settings → Terminal and fill in:

Setting	Nets	Verifone Android	Verifone P400
Terminal type	Nets / Baxi	Verifone	Verifone P400
Bridge address	`127.0.0.1`	`127.0.0.1`	`127.0.0.1`
Bridge port	`5100`	`5101`	`5102`
Payment method name	`NetsTerminal`	`VerifoneTerminal`	`VerifoneTerminal`

Use 127.0.0.1 when the bridge runs on the same PC as the app. If the bridge runs on a separate PC on the same network, enter that PC's IP address and ensure the firewall port is open there.

Use Test connection in the settings screen to verify the bridge is reachable and the terminal is ready before opening for the day.

Payment Terminal Setup

Setup overview

Supported integrations

POS app settings

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