User's Manual

PIN Pad 791 Programmer’s Manual (PCI POS-A) UDN PM0103-U Rev. 06
Section 9 – Online transaction messages with Master / Session keys 2015-04-20
Page214
Uniform Industrial Corp. Proprietary and Confidential Total 342 pages
Message flow:
Normal frame
HOST Direction PIN Pad
Message Z3


<ACK> (Good LRC)
<NAK> (Bad LRC)
<EOT> (after 3 NAKs)
Display prompts as required
Authenticated frame
HOST Direction PIN Pad
Message Z3


<ACK> (Good LRC)
<NAK> (Bad LRC)
<EOT> (after 3 NAKs)

Message Z3
(response frame)
<ACK> (Good LRC)
<NAK> (Bad LRC)
<EOT> (after 3 NAKs)


Display string
<EOT> (if received <ACK>)