Synchronous Mode

Messages in synchronous mode require a response from the POS application. They are typically sent by IPC so the EPOS operator can enter additional transaction data e.g. manual authorisation details where a card has been referred; or can influence the transaction flow.

The request from IPC is in the form of key value pairs sent on the Message port. The response from the EPOS application should be sent on the same port.

Following is the list of attributes IPC can send during transaction:

Following is the list of attributes EPOS can send during transaction:

The synchronous mode example below is for a Sale transaction where IPC requests Accept/Reject Signature

Accept/reject Signature

This request is issued by IPC on the message port when a transaction requires signature validation.

Request from IPC:

2=401
3= AUTH CODE:XXXXXXIs Signature Ok ?
99=0

The response from the EPOS application is in the format below

Response from EPOS:

2=401
3= 0  ( Accepted), 1 (Rejected)
99=0

Referral Request

This request is issued by IPC on the message port when a transaction is referred by the acquiring bank and requires the EPOS application either to reject it or to supply a manual authorisation code to complete it.

The IPC request provides the information required by the EPOS operator to contact the acquiring bank i.e. the contact numbers and the merchant id (MID) in use for the transaction.

Request from IPC:

2=400
3=CALL BANK Amount:xx.xx
11=MID e.g. 21249872
12=Acquirer contact numbers e.g. 02083871299,02083871295
99=0

Response from EPOS:

2=400
3=0 (Accepted), 1  (Rejected)
4=Authorisation Code received from bank (Present only if the above value is 0)
99=0

Fallback Confirmation Request

This request is issued if a transaction requires card fallback i.e. the card cannot be verified using the optimum method available on both the card and terminal. IPC issues this request when a magnetic swipe card falls back. The intention is that the sales operator may reject fallback and thereby cancel the transaction if there is any doubt about it.

Request from IPC:

2=402
3= Swipe card fallback allowed ?
99=0

Response from EPOS:

2=402
3= 0 (Accepted), 1 (Rejected)
99=0

CNP Confirmation Request

IPC will send this request to EPOS application for CNP Confirmation if merchant has selected AVS details Mandatory in YESEFTConfig. However, if merchant has selected AVS details Mandatory and Apply AVSRules in YESEFTConfig then IPC will not send this request.

Request from IPC:

2=403
3=Security Code Matched, Address Matched, ZIP code Matched
99=0

Response from EPOS:

2=403
3= 0  (Accepted), 1 (Rejected)
99=0

Cashback Confirmation Request

Where IPC is enabled to allow cashback, and a cashback candidate card is read by the PED, IPC will send this request to the EPOS application to confirm cashback, and the cashback amount. If the cashback amount is greater than the allowed limit, IPC sends an error message and will attempt the cashback request twice more. If IPC does not receive valid amount in three attempts then IPC will process the transaction with the original amount.

Request from IPC:

2=405
99=0

Response from EPOS:

2=405
3= 0 (Accepted), 1 (Rejected)
5=Cashback amount (present only if the above value is 0) e.g. 50.00
99=0

Address and Postcode (ZIP code) Enter Request

The Address and Postcode (ZIP code) request is issued under these scenarios:

CNP transaction

If the merchant has selected ‘AVS details Mandatory’ in YESEFTConfig, IPC will always send the request below to the EPOS application to prompt for entry of CNP address and postcode/ZIP code details. However, if the merchant has selected ‘AVS details Mandatory and Apply AVSRules’ in YESEFTConfig, this request will be sent according to the AVS confirmation rules set. Similarly, if the merchant has selected only ‘Apply AVSRules’ in YESEFTConfig, then IPC will send this request according to the AVS confirmation rules.

Keyed/Forced keyed Referral transaction

This request is issued on message port for Keyed/Forced keyed referral transactions if IPC is being used with Worldpay US acquirer using the Vx820 PED. IPC prompts for Card number, expiry date, CVV and State code on the PED. CVV and State code are not mandatory entries.

After these entries on the PED are complete, IPC will send the request below to the EPOS application for Address and ZIP code entry. If the merchant does not have the values for Address and ZIP code then both the fields can be sent empty with accept response (3=0). In the Keyed/Forced keyed scenario this message port request is not configurable through the AVS details tab.

Request format

According to the CNP rules configured, the application can prompt

Only for Address, request from IPC :

2=407
3=Address
99=0

Expected Response from POS:

2=407
3=(Accepted), 1 (Rejected)
7=Cardholder Address
99=0

Only for ZIP code, request from IPC:

2=407
3=ZipCode
99=0

Expected Response from POS

2=407
3=(Accepted), 1 (Rejected)
8=Cardholder Zipcode
99=0

For both Address and ZIP code, request from IPC:

2=407
3=Address,ZipCode
99=0

Expected Response from POS:

2=407
3=(Accepted), 1 (Rejected)
7=Cardholder Address
8=Cardholder Zipcode
99=0

Cancel Transaction Request

This request is issued by IPC on the message port after having commenced a new transaction (Sale or Refund). Whilst the ‘Insert or Swipe Card’ message is displayed on the PED. the transaction may be cancelled by sending a string formed of the keyword ‘Cancel’ on the message port.

The string is not case sensitive can be send in either capital or small letters.