Receive terminal notifications

Outlines handling messages and events sent from the terminal to the sale system.


Progress events are sent from the POI (also known as Pin Entry Device (PED)) to the Sale system (also known as Point of Sale or Cash Register). Progress events do not require any action by the cash register. They inform the staff of what is happening on the POI.

To receive progress events, the Sale System or Sale Server must run a HTTP server. Contact the Support Team to configure these end-points (IP or URL).

Progress events are returned in the ReferenceID, as an event value (possible values are listed in the Progress events section). ReferenceID is form encoded and can contain multiple values, including eventTransactionID (POI ID / tender reference) and timestamp.

For Display requests, the ServiceID of the original request is included, and the Device ID will differ for each display request.

If an Event notification refers to a specific request, the header will include the ServiceID of that request, otherwise the ServiceID will not be included.

The SaleID and ServiceID in the MessageHeader should be unique. SaleID and ServiceID combinations are rejected if used recently, within 48 hours.

No content is expected in the HTTP response body for these messages. If the response does not arrive, we do not retry.

There are two types of messages, display messages and event notifications.

  • Display messages: messages and events sent during services (such as payment) that include transaction status information. Will be sent to the IP that started the transaction (in a local setup) and at endpoints configured by the POS Support Team
  • Event messages: sent to the Sale System outside of the payment flow, for example, going down for maintenance, available after maintenance, etc.