Compaq 99875320-5 Manual De Usuario

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Section 4.  USB Communications 
 
Item Value 
(Hex) 
Input (Data, Variable, Absolute, Buffered Bytes) 
82 02 01 
Usage (Track 3 data) 
09 32 
Report Count (110) 
95 6E 
Input (Data, Variable, Absolute, Buffered Bytes) 
82 02 01 
Usage (Command message) 
09 20 
Report Count (24) 
95 18 
Feature (Data, Variable, Absolute, Buffered Bytes) 
B2 02 01 
End Collection 
C0 
 
CARD DATA 
 
Card data is only sent to the host on the Interrupt In pipe using an Input Report.  The device will 
send only one Input Report per card swipe.  If the host requests data from the device when no 
data is available, the device will send a Nak to the host to indicate that it has nothing to send.  
When a card is swiped, the Input Report will be sent even if the data is not decodable.  The 
following table shows how the input report is structured. 
 
Offset Usage 
Name 
Track 1 decode status 
Track 2 decode status 
Track 3 decode status 
Track 1 data length 
Track 2 data length 
Track 3 data length 
Card encode type 
7 – 116 
Track 1 data 
117 – 226 
Track 2 data 
227 - 336 
Track 3 data 
 
TRACK 1 DECODE STATUS 
 
Bits 7-1 
Value Reserved  Error 
 
This is a one-byte value, which indicates the status of decoding track 1.  Bit position zero 
indicates if there was an error decoding track 1 if the bit is set to one.  If it is zero, then no error 
occurred.  If a track has data on it that is not noise, and it is not decodable, then a decode error is 
indicated.  If a decode error is indicated, the corresponding track data length value for the track 
that has the error will be set to zero and no valid track data will be supplied. 
 
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