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Oracle® Retail EFTLink Core Configuration Guide
Release 18.0
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5 Merchant Link

This chapter describes the Merchant Link implementation.


This Merchant Link implementation is for use with any compatible terminal that has Merchant Link firmware installed, with communication based on a socket protocol.

EFTLink General

This document assumes static EFTLink configuration. When deploying with a POS that supports dynamic configuration, all property settings referred to below should be set on the POS, and not directly into local property files.

Minimum Version

The Merchant Link interface requires a minimum EFTLink version of 16.0.3.

System Architecture

Merchant Link is deployed as an intelligent terminal. EFTLink connects directly to the PoslynxMINI device which in turn connects to the Verifone MX925 device using a proprietary socket/XML protocol. The PoslynxMINI device acts as a message broker to the MX925 device. The MX925 device will need to know the PoslynxMINI device address. When setting up the system for the first time it is best to contact Merchant Link who will be able to talk through the process.


In addition to standard EFTLink files:

  • poslynxcore.jar – executable code for the Merchant Link EFTLink core.

  • poslynx.properties – configuration settings to specify which features are enabled and to define communication parameters for the interface with the terminal.

  • Lang<CC>_<Core>.properties – Language translation file, for further information see Language.


If the POS supports dynamic configuration, properties can be set there instead of in poslynx.properties.


The translation files for this core should not require alteration, but if necessary then this can accomplished by amending the relevant Lang<CC>_<Core>.properties within the base eftlink folder.

The language used will follow the language set in the EFTLink framework; see the Oracle Retail EFTLink Framework Installation and Configuration Guide, EFTLink General Information, Translation section.


DisplayLanguage = EN

Supported country codes are: CN, DE, EN, ES, FR, IT, JP, NL, PT, RU and SV.

Core Classname

The following should have been set in the EftlinkConfig.properties file by installcore.bat or installcore.sh:

EPSCore0 = manito.eft.poslynx.PoslynxCore

Configuration Settings

The full set of configuration properties is defined and commented in poslynx.properties.

Key Settings

Settings that may be different for each POS/PED.

The Core will connect to the PoslynxMINI device, this device is connected to the internet and the LAN and is accessible by Merchant Link. The device is DNS enabled and will have an address of the following format:

Table 5-1 Merchant Link - Key Settings

Setting Description Example


IP of PoslynxMINI device.

TerminalIP =

Secondary Settings

Table 5-2 Merchant Link - Secondary Settings

Setting Description Default Example


Port number.


TerminalPort = 5015


Connection time out in seconds.


ConnectionTimeout = 10


Overall response timeout in seconds.


ResponseTimeout = 300


Maintenance menu selection timeout in seconds.


MaintenanceTimeout = 60


Option to buffer customer printout generated during the transaction and then include it in the POS authorization response so that it can be merged with the POS receipt line to form a single receipt/voucher.


EmbeddedPrinting = false


Trigger/key in receipt text to indicate that a paper signature is required.




Whether to enforce an electronic signature capture for credit transactions over a designated value.


SignatureCaptureEnabled = false


Floor limit to be applied if SignatureCaptureEnabled is set true.


SignatureCheckFloorLimit = 5.00


Timeout in seconds on waiting for signature.


SignatureCheckTimeout =


Maximum line item description length allowed by comms protocol or visible on terminal.


MaxLineItemTextLength =


Maximum number of line items allowed in a single message.


MaxLineItems = 10


Maximum number of separate line item update messages it is practical to send before it becomes too cumbersome and slow.


MaxLineItemUpdates = 20


Whether to include line items in the voucher.


ShowlineItemsOnVoucher = false


Keyword or phrase that identifies start of item summary on voucher.


ReceiptLineItemStartTag = QTY DESCRIPTION


Keyword or phrase that identifies start of item summary on voucher.


ReceiptLineItemEndTag = Total:


Whether to remove EMV tags from the EFT voucher.


ShowEMVTagsOnVoucher = false


A comma separated list of text from the response indicating the operator to call for voice authorization.


VoiceAuthorizationIndicators = R001 CALL VOICE AUTH - REFERRAL


Whether to send the Lane ID to the TL device.


AddLane = false


Whether to print the merchant copy of the receipt.


PrintMerchantCopy = true


Enforced minimum gap interval in milliseconds between messages.


MinimumInterMessageGap = 10


The client merchant access code sent to TL device.


MerchantAccessCode = FFFFFFFFFFFF


Client ID sent to TL device.


ClientID = 1


Encryption type sent to TL device.


GiftCardEncryptionType = 64


The lane ID sent to the TL device.


LaneID = L1


Whether to enable TL-controlled SAF processing.


EnableSAF = true


Whether to support TL-controlled SAF processing for voice authorization.


SupportSAFForVoiceAuthorization = false


Minimum number of characters for the authorization code for voice authorization.


MinimumAuthCodeLength = 1


Maximum number of attempts to capture the authorization code from the operator.


MaximumGetAuthCodeAttempt = 3


Whether POS triggered batch close is enabled in the administrative functions.


EnablePOSTriggeredBatchClose = false


The vendor name of our middleware sent to the TL device.


MWVendor = Oracle


The official name of our middleware sent to the TL device.

Oracle Retail EFT Link

MWModel = Oracle Retail EFT Link


Whether to send the InvoiceNum or POS transaction number to the TL device.


SendInvoiceNum = true

Supported Functions

Below is a list of supported functionalities of the interface to Merchant Link. Many functionalities are provided by Merchant Link, such as Loyalty, Cashback and so on, (please refer to interface specification for details) but are not implemented because of the business requirement.

Administration Functions

The terminal has some administration/maintenance functions. These are normally invoked from a dedicated EFT Maintenance button, but if this is not available, they could be accessed by an engineer using the EFTLink built-in test harness.

EFTLink uses DeviceProxy messages to display input prompts on the POS to manage these functions.

Table 5-3 Merchant Link - Administration Functions

Function Description

Local Connection Test

Sends a request to test the connection to the device. This Core builds an XML request with the "CONNECTIONTEST" command and should receive a response with an "APPROVED" result if successful.

Host Connection Test

Sends a request to test the connection between the device to the MerchantLink gateway. This Core builds an XML request with the "CONNECTIONTEST" command and should receive a response with an "APPROVED" result if successful.

Pin Pad Reset

This command will terminate any pending transaction on the pin pad and return the pin pad to its 'ready' state. For the VeriFone and Equinox pin pads, the pin pad will display the 'Welcome' screen. For the Ingenico pin pads, the pin pad will display the respective offline form.

Pin Pad Reboot

Sends the PPREBOOT command which reboots the pin pad.

Signature Capture

Sends request to test the signature capture functionality on the device.

Batch Summary

Sends a batch summary request to the terminal. This provides a summary report of the current information for that batch of transactions prior to settlement. It should be considered as flash report typically referred to as an X read report.

Batch Report

Sends a batch card totals request to the terminal. This will return a report which will summarize the card type totals for the current batch prior to settlement.

Batch Close

Sends a batch close request to the terminal. This will initiate a batch close process on the host processor which triggers transactions to be submitted for financial settlement. This returns a day end report.

Get Versions

Sends a request to get the firmware versions of the TL device. The details are displayed to the operator.

Pin Pad EMV Configuration

Sends a request to reset the pin pad. This command will force the terminal to restart after acquiring Certificate Authority Public Key (CAPK) file from the host processor.into the pin pad.

Contact NetVu Management Server

Sends the CONTACTNETVU command which contacts the NetVu management server and uploads the current diagnostic and statistics log files on the TL device to NetVu.

Run Diagnostics Utility

This command executes the Diagnostics Utility. The Diagnostics Utility is an application on the TransactionLink device that can be used to verify if the installation/set-up is correct. The Diagnostic Utility will use the pin pad to display a sequence of system and configuration information, one parameter at a time. The user can then compare and confirm if the set-up is using the correct parameters as displayed.

Invoice Detail

Sends a request to retrieve the details of the most recent financial transaction.


Sends payment request to the terminal. Terminal will return a response message with unformatted receipt strings for customer and/or merchant receipts.

In an event of referral where authorization cannot be obtained online then a prompt for authorization code will appear; authorization code must be obtained via telephone and entered here.

If successful, appropriate receipts will be printed at the end of transaction.


Sends reversal request to the terminal. This will reverse a transaction specified by the transaction number, found on the receipt, which must be captured by the POS and pass on to EFTLink.


Sends refund request to the terminal. This will refund a transaction with specified amount.

Sale State Notifications

Sends line items through to the device so the customer display can be updated in line with the POS.

SVC Payment

Sends a gift or merchandise credit card payment request to the terminal. If there are not enough funds available, only the funds available will be deducted. The POS client will have to settle the transaction with another tender in this scenario.

SVC Activate

Sends a gift or merchandise credit card activation request to the terminal.

SVC Deactivate

Sends a gift or merchandise credit card deactivation request to the terminal. The account is disabled after this as the request is intended to be used for lost or stolen cards. It is not possible to use the card or account once this request has been issued and accepted

SVC Add Value

Sends a gift or merchandise credit card add value request to the terminal. This will only add value to an account that has been activated.

SVC Balance Enquiry

Sends a gift or merchandise credit card balance enquiry request to the terminal.

SVC Unload (Cashout)

Sends a gift or merchandise credit card cash out request to the terminal. All funds are deducted from the account and the cash back amount is returned to the POS. The account is not deactivated as part of this process.