# How it works

Integration options, payment flow, and requirements for Oracle Simphony POS+.

## Overview

Oracle Simphony is a point-of-sale platform widely used in hospitality. New Simphony deployments use SPI (Simphony Payment Interface) instead of the legacy OPI API. PXP POS+ integrates with Simphony through the Oracle SPI adaptor, so Simphony sends payment requests to your terminal and POS+ handles card capture and authorisation through Unity.

## Integration options

PXP supports two Simphony POS+ configurations:

| Option  | Simphony client | Payment device | Typical use |
|  --- | --- | --- | --- |
| [Pay at Counter](/guides/point-of-sale/pos-plus/oracle/pay-at-counter) | Windows workstation | Separate terminal (PED) | Fixed checkout, counter service |
| [Pay at Table](/guides/point-of-sale/pos-plus/oracle/pay-at-table) | Android on same device as POS+ | Castles S1F4 Pro (All-in-One) | Mobile table service |


Both options use the same SPI interface and TLS security model. TLS with certificate-based authentication is coming soon; in the meantime, Operators must set the workstation connection status to **HTTPS without validation**. See [Setup](/guides/point-of-sale/pos-plus/oracle/setup).

## What Simphony controls

Simphony initiates payments. Your team does not call POS+ directly for day-to-day transactions.

Instead:

1. The cashier completes the sale in Simphony.
2. Simphony sends the payment request to POS+ on the payment device.
3. The customer presents their card on the terminal.
4. POS+ authorises the payment through Unity and returns the result to Simphony.


## Supported capabilities

Pay at Counter and Pay at Table support the same capabilities:

| Capability | Supported  |
|  --- | --- |
| Purchase |  |
| Standalone refund |  |
| Void | Acquirer-dependent.Void of refund: AIB, Elavon, and Lloyds Cardnet only. |
| Gratuity |  |
| Mandatory service charges |  |
| DCC | AIB and Elavon only. |


Confirm void and DCC eligibility with your PXP account representative for your acquirer and device mix.

## Requirements

You need the following for a supported deployment:

- **Oracle Simphony:** v19.1 minimum; v19.9 is recommended for the latest gratuity and service charge features.
- **Castles device:** S1F2, S1F4 Pro, or S1P2 for Pay at Counter; S1F4 Pro only for Pay at Table. See [Devices](/guides/point-of-sale/pos-plus/devices) and [Acquirers](#acquirers).
- **Unity:** Merchant, site, and terminal configured with POS+ adaptor type *Oracle SPI*. See [Add and activate a device](/guides/point-of-sale/pos-plus/oracle/setup#add-and-activate-a-device).
- **Network:** See [Network requirements](/guides/point-of-sale/pos-plus/oracle/setup#network-requirements).


## Acquirers

Use this section when scoping a hospitality deployment or confirming what your venue can accept through Oracle Simphony and POS+.

| Acquirer | DCC | Pay at Counter devices | Pay at Table (All-in-One) |
|  --- | --- | --- | --- |
| AIB |  | S1F2, S1F4 Pro, and S1P2 | S1F4 Pro |
| Elavon |  | S1F2, S1F4 Pro, and S1P2 | S1F4 Pro |
| PXP Acquiring |  | S1F2, S1F4 Pro, and S1P2 | S1F4 Pro |
| Lloyds Cardnet |  | S1F2 only |   |


Lloyds Cardnet on Pay at Counter is currently limited to S1F2. Confirm device availability with PXP before proposing All-in-One to Lloyds Cardnet merchants.

Enable DCC in Unity when your acquirer supports it. See [Dynamic currency conversion](/guides/point-of-sale/pos-plus/dcc).

## Card schemes

Card scheme support by acquirer is as follows:

| Scheme | Supported | Acquirer |
|  --- | --- | --- |
| Visa |  | All |
| Mastercard |  | All |
| American Express |  | Elavon, AMEX |
| Diners / Discover |  | Elavon, AIB, Lloyds Cardnet |
| JCB (contact) |  | Lloyds Cardnet |


## Get started

Start with these steps:

1. [Configure the Unity Portal, activate your device, and connect Simphony](/guides/point-of-sale/pos-plus/oracle/setup).
2. Choose your integration and run payments: [Pay at Counter](/guides/point-of-sale/pos-plus/oracle/pay-at-counter) or [Pay at Table](/guides/point-of-sale/pos-plus/oracle/pay-at-table).