OBID i-scan
®
System-Manual
ID ISC.MR200
FEIG ELECTRONIC GmbH
Page 20 of 144
H40801-5e-ID-B.doc
The Reader supports both Protocol frames, standard and advanced protocol frame. The Host Applica-
tion can chose which protocol frame is used. If the host application chose advanced protocol frame the
Reader will always response with advanced protocol frame. If the host application chose the Standard
Protocol frame the Reader’s response will depend on the length of the response. If the host request
leads to a response with more than 255Byte the Reader will chose the advanced protocol frame as
response frame otherwise the Reader response uses the standard protocol frame.
Information on:
STX:
If the responded protocol of the Reader starts with the STX sign (0x02) the protocol
frame is Advanced Protocol-Length. Then the protocol length is defined by the 2
Byte Parameter ALENGTH.
ALENGTH (n = 8...65535):
Number of protocol bytes including STX, ALENGTH and CRC16
LENGTH (n = 6...255): Standard Protocol-Length (up to 255 Byte)
Number of protocol bytes including LENGTH and CRC16.
COM-ADR:
0..253 address of device in bus mode
Note:
The Reader can be addressed via COM-ADR 255 at any time!
CONTROL-BYTE:
Defines the Command which the Reader should operate.
STATUS
1
:
Includes the status message or protocol data from or to the Reader.
DATA:
Is a optional data field with variable length. The number of DATA byte depend on the
command. The data will be sent always as MSB first if the Reader is in the ISO-Host
Command Mode.
CRC16:
Cyclic redundancy check of the protocol bytes from 1 to n-2, as specified by CCITT-
CRC16
Polynom:
x
16
+ x
12
+ x
5
+ 1 (0x8408)
Start Value:
0xFFFF
Direction: Backward
1
see ANNEX D: Index of Status Bytes
