Intermec 6804DM, Техническое справочное руководство

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SECTION 4 Operation
Intermec Portable Printers Technical Reference Manual 4-47
Most smart card operating systems (inside the smart card)
do not provide a method of “reading the directory (file struc-
ture)”. The file structure and security features are unique
to the application. So although the reader gives access to
“standard card types” (as defined in ISO--7816), it is not
possible to “automatically” read and buffer the smart card
data.
Each application should have a predefined card type as well
as use of that card; the handheld should then have that
knowledge. The application, then, might choose to handle a
microprocessor--based smart card as follows:
"
Handheld prompts the user to insert their card.
"
User inserts the smart card into the card reader slot
waking up the reader>
"
Handheld polls the reader looking for the card to be
inserted.
"
Handheld commands reader to power up the card;
reader returns the card’s answer to reset (unique to
each card type).
"
Handheld commands reader to pass commands and
data to the card, selecting files and providing pass-
words and cryptographic keys as required.
"
Reader returns smart card’s response to each com-
mand and data sent from the handheld, allowing the
handheld to determine if proper access has been at-
tained.
"
Handheld requests data from the card, and reader re-
turns that data.
"
Handheld provides command with data to be written
to the card, and the reader passes that command and
data to the card and returns the card’s response.
"
When the transaction is complete, the handheld
prompts the reader to power down the card, then
prompts the user to remove the card.