TransCore encompass 4, Руководство пользователя

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Encompass 4 Reader System Guide
TransCore Proprietary.
7–130
Reader response:
Done
697 Set User-Programmable Group Select Equals (GSE) Filter
Refer to “549 Display User-Programmable Group Select Equals (GSE) Filter Data” on page 7–111.
Command #697 assigns the user-programmable GSE filter.
The command string is assigned according to the following format:
#697 MM AA DDDDDDDDDDDDDDDD
Where
MM =
The tag uses this mask to determine which of the eight Comparison Data bytes are to
be compared for the Group Select filter (1-byte field, 2 characters).
For example:
#697
30
00 000063B400000000
MM = 30: 00 11 0000
In this example, the mask indicates to the tag to compare data in position 02 and 03
after address 00.
AA = This field is used by the tag to determine the start address in the tag memory for the
comparison data (1-byte field, 2 characters).
#697 30
00
000063B400000000
For example, using the SeGo ID E02263B4002C9232:
E0 22 63 B4 00 2C 92 32 – SeGo ID
┬ ┬ ┬ ┬ ┬ ┬ ┬ ┬
00 01 02 03 04 05 06 07
– Byte locations/addresses starting at 0
DD…DD = Comparison Data: an 8-byte field (16 characters) used by the tag as the comparison
data for the Group Select Equals filter. The tag compares the data in this field to data
in tag memory beginning at the Start Address to determine if the tag will respond to a
reader Group Select request. Only the bytes having the corresponding bit set in the
Mask is used for this comparison.
For example, consider two tags with the following SeGo ID:
SeGo ID:
E022
63B4
002C9232
SeGo ID:
E022
63B4
002D8132
These two SeGo IDs have the same information in bytes 02 and 03 (63B4), so both of
these tags will respond to the reader.
The Group Select Equals filter written as follows will cause only tags with 63B4 in bytes
02 and 03 to respond.
#697 30 00 0000
63B4
00000000
The 2-character Address indicates where the Group Select filter starts. Anywhere
there is a 1 in the binary representation of the 2-character hexadecimal Mask, the tag