User's Manual

PIN Pad 791 Programmer’s Manual (PCI POS-A) UDN PM0103-U Rev. 06
Section 6 – Contact EMV Level 2 transaction messages 2015-04-20
Page110
Uniform Industrial Corp. Proprietary and Confidential Total 342 pages
Message T27 Get Online authorization Data
Format: <STX>T27<ETX>[LRC]
Message length: Fixed 6 bytes.
Usage: Issue this message to get data (EMV) for online authorization.
Message element:
Field Length Value and description
<STX> 1 <02>
T27 3 Message ID
<ETX> 1 <03>
[LRC] 1 Checksum
While the EMV transaction must be authorized online, issuing message T27 to get the necessary data for
online authorization from PIN pad. If the transaction must be authorized online, PIN pad
User can load a tag list for online authorization data into PIN pad, PIN pad will search the corresponding
values according to the tag list and return it as transaction record. Please refer to Appendix D for more
details.
Message flow:
HOST Direction PIN pad
Message T27


<ACK> (Good LRC)
<NAK> (Bad LRC)
<EOT> (after 3 NAKs)

Message T28
<ACK> (Good LRC)
<NAK> (Bad LRC)
<EOT> (after 3 NAKs)
