Intermec Transaction Manager 9560, Руководство пользователя

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Interactive Reader Language
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Magnetic Card Reader Commands
The magnetic card reader accepts many data formats. Use the commands in
this section to specify your data format and to create custom IRL programs.
Reading Standard Data
The host may request the data from the reader in two ways:
Single Byte Command Standard card data is read from the corresponding track
location. For example, standard track 2 data is read at track 2 on the card.
Double Byte Command
A particular track format is read from a different track
location. For example, track 1 format is read on track 2. The command is
followed by an ASCII number (1, 2, or 3) representing the ANSI track format
for processing the data.
Reading Custom Data
The magnetic card reader accepts custom data with 3 to 7 bits per word. Use
one of two methods to read custom data:
• If the data does not contain NULL characters (all bits zero), then use the
2-byte command.
• If the data contains NULL characters, then you must insert an “Underline”
(5F) between the 2 bytes. The card reader stores all bits found in the card,
starting with the first 1 bit. The card reader ignores the last 10 bits at the
end of the card.
The IRL program must request data from the card reader using the following
structure:
Transmit custom data (fwd/rev.) Track X (X = Track #, 1-3).
“Underline” (if data with NULL is expected)
Number of bits per character (3-7)
The card reader takes the number of bits specified for each character, adds the
selected parity, and then transmits all the data. The read sequence starts when
the card reader locates the first “1” in its storage and ends with the last
character found.