Magtek DynaPro Mini, Programmer'S Manual

Page: 28 / 128

3 - Command Set
DynaPro Mini| PIN Encryption Device | Programmer’s Manual (Commands)
Page 28 of 128 ( D99875629-43 )
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F9 will always include nested TLV data object DFDF55 containing a MAC Encryption Type,
which specifies which key and variant was used to generate the MAC. See the definition of
DFDF55 in
Appendix D MagTek Custom EMV Tags (EMV Only) for information about
valid values.
o
F9 will always include nested TLV data object DFDF25 containing the device’s unique IFD
Serial Number, which the host can read from the device. See
Appendix D MagTek Custom
EMV Tags (EMV Only) for details about retrieving tags.

The end of the message outside the F9 data object is padded to ensure that the length of data, starting
with the F9 byte at the beginning, and ending with any additional padding, is a multiple of 8 bytes.
This is a requirement of using the CBC-MAC algorithm.

Using the key specified in the message’s documentation, the CBC-MAC is calculated over the block
of data that starts with the F9 byte at the beginning, through the last byte of any additional padding.
This yields an 8-byte CBC-MAC.

The final 4 bytes of the message are populated with the most significant 32 bits of the 8-byte CBC-
MAC, not in TLV format.

If the host is sending the message, it will send it to the device using Command 0x10 - Send Big
Block Data to Device . If the device is sending the message as part of a response or report, it will
send it to the host using Report 0x29 - Send Big Block Data to Host .