Magtek eDynamo, Programmer'S Manual

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8 - Commands
eDynamo| Secure Card Reader Authenticator | Programmer’s Manual (COMMANDS)
Page 95 of 245 ( D998200115-17 )
8.4 Command Group 0x03 - EMV L2 (EMV Only, Extended Commands Only)
When calling Command 0x49 - Send Extended Command Packet (Extended Commands Only) , a
value of
0x03
in the most significant byte of the Extended Command Number is reserved for EMV L2
commands, which are documented in this section.
8.4.1 About EMV L2 Transaction Flows (EMV Only)
The general flow of an EMV L2 transaction is as follows (bear in mind the device does not have a
display, so in these steps the host drives the user interface for both the terminal operator / cashier and for
the cardholder / customer):
1) The terminal operator / cashier performs steps external to the transaction, generally resulting in a total
balance owed, and directs the host software to initiate a transaction.
2) The host software sends the device Extended Command 0x0300 - Initiate EMV Transaction
(EMV Only) . From this point until the host sends the device transaction results to the transaction
processor, the host may cancel the EMV transaction by sending Extended Command 0x0304 -
Cancel Transaction (EMV Only) .
3) If the cardholder has not already presented payment, the device sends the host Notification 0x0300 -
Transaction Status / Progress Information , followed by Notification 0x0301 - Display Message
Request to prompt the cardholder to PRESENT CARD . The device waits until the user presents
payment, pending a timeout.
4) (MSR Only) At this point, if the MSR is enabled and Extended Command 0x0300 - Initiate EMV
Transaction (EMV Only) indicated the MSR should be armed, the cardholder may swipe a magnetic
stripe card:
a) On devices that do not support EMV MSR Flow (see Table 1-2 ), the device cancels the EMV
transaction the host initiated, and reverts to the behavior described in section 6 Magnetic Stripe
Card Data Sent from Device to Host (MSR Only | Keypad Entry Only) .
5) (Contact Only) If the cardholder has inserted a chip card, the device attempts to communicate with
the card. If it is unable to do so:
a) (Contact Only) On devices that do not support EMV MSR Flow (see Table 1-2 ), the device
immediately terminates the transaction with no retries and sends the host Notification 0x0300 -
Transaction Status / Progress Information to report the failure.
6) (Contact Only) If the cardholder has inserted a chip card, and the card reports to the device that the
cardholder should select a language, the device sends the host
Notification 0x0302 - User Selection
Request to present a selection menu to the cardholder. After the cardholder selects a language, the
host passes the selection to the device by sending Extended Command 0x0302 - User Selection
Result (Contact Only) .
7) (Contact Only) If the cardholder has inserted a chip card, and the card holds more than one payment
application, the device sends the host
Notification 0x0302 - User Selection Request to prompt the
cardholder to select which application to use. After the cardholder selects an application, the host
passes the selection to the device by sending
Extended Command 0x0302 - User Selection Result
(Contact Only) .
8) The device communicates with the chip card or contactless payment device, and keeps the host and
cardholder apprised of progress by sending one or more
Notification 0x0300 - Transaction Status /
Progress Information and Notification 0x0301 - Display Message Request .
9)
If the device’s EMV configuration [see
Extended Command 0x0311 - Read EMV Configuration
(Contact Only) ] does not specify Online Only transactions, the device consults the chip card or
contactless payment device to determine whether to approve or decline the transaction offline, or
perform the transaction online with the approve/decline decision made by the transaction processor.