CSI CARDPIN1, Installation Manual

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Installation Guide ABA Readers
CSI Readers 15
ABA Readers
The door processing units can receive standard TTL level Data and Strobe lines from an
ABA magnetic stripe reader. CSI’s DPUs use standardized data recovery and interpreta-
tion as defined on the ABA track (Track 2 - center track) of a magnetic stripe card. The
ANSI/ISO standard (ANSI x4.16-1983/ISO 3554) defines this format.
ABA Data Format
Compatibility with standard ABA encoded cards facilitates the use of many off-the-shelf,
low-cost, mag-stripe readers and cards. The data is encoded on the mag-stripe as a
sequence of 5-bit hexadecimal digits (4 bits plus odd parity on each digit). The ABA
format described in ANSI x4.16 is oriented as shown below.
The following is a sample Track 2 data string.
Data is transmitted with the least significant bit first within the ABA digit format, and
most significant digit first within the CSI field format. The ABA data format used with
the CSI DPUs is broken into five sequential digit fields, left to right on the encoder
display.
Table 5 lists each digit field as it appears on the display.
BBBBP
0123
00000 Leading zeros
11010 Start sentinel
xxxxP Variable length data field (up to 37 digits)
"
"
xxxxP
11111 Stop sentinel
xxxxx
LRC character (longitudinal even parity on all bits from start
sentinel to LRC)
00000 Trailing zeros
Leading zeros Start sentinel
5
Data
3
Data
4
Data
7
Data
Stop sentinel LRC
Trailing
zeros
000... 11010 10101 11001 00100 11100 11111 10000 000...