Intermec 6804DM, Техническое справочное руководство

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SECTION 4 Operation
Intermec Portable Printers Technical Reference Manual 4-45
until the host requests the data. Data is flushed either
when the host explicitly requests that the buffer is zeroed
or when the printer falls asleep.
Smart cards, however, vary widely and many have specific
security issues (such as passwords, cryptographic keys, and
application knowledge of file structure) that must be pre-
sented to gain access to data stored on the card. For smart
card applications, the 6804 and 6808TCR printers acts as a
conduit for commands and data from the host, and returns
data sent from the card.
In normal operation, the printer will probably be asleep
when any card or button transaction begins.
1. The printer will wake up whenever a magnetic card or
smart card is inserted, or the probe is touched to a
button.
2. The button is read automatically whenever the printer
is awake and the button is sensed by touching with
the probe.
3. The magnetic card is read when the printer is awake
and the card is moving.
4. This data is stored in an internal buffer in the printer
and available to the host via RS--232 or IrDA.
5. Data directly from the smart card can be read by com-
mand from via RS--232 or IrDA
Magnetic Card Reader
Although insertion type card readers such as the one used
on the reader can read cards either upon insertion or with-
drawal, the read rate is much higher upon withdrawal with
virtually all readers of this type (e.g. the gas pump read-
ers). This is because the card is unstable and the rate of
movement can change drastically when the card is first in-
serted.
If the reader is already awake, and more than one card
could be inserted, the application may choose to zero the