MagTek P-SERIES USB - Manual (Page 17)

9
SECTION 3. OPERATION
A card may be read by inserting it into the Reader slot or removing it from the Reader slot. The
direction of the read that is sent to the host is controlled by the MSR_DIRECTION property,
which is described in the next section. The magnetic stripe must face toward a read head during
the swipe. Once the card is swiped, the reader will attempt to decode the data and then send the
results to the host via a USB HID input report or, if in Keyboard Emulation mode, as if the data
was being typed on a keyboard. After the results are sent to the host, the reader will be ready to
read the next swipe. To help reduce read errors, if a good read occurs when the card is inserted
and a bad read occurs when the card is removed, then the read data for the card insert will be sent
to the host when the card is removed instead of the bad read data from the removal.