20
Applications
6-3. Changing the error check system
Normally, the error for communication format can be checked according to the
aforementioned
“Equipment No
～
ETX
’ s CRC-CCITT”, however, it can be changed into
“Compare (twice)” system.
To change the communication checking system, use the DIPSW
“8” on CPU board built in the
Indicator unit.
Turn off the power source before changing the setting.
Check system
DIPSW 8
CRC-CCITT system
OFF
Compare (twice) system
ON
For the Compare (twice) system, unless the same transmitted sentence is repeated twice
continuously, it will be judged as an error. Compared with the
“CRC-CCIT” system, it takes
longer time for error checking, however, since there is no need to add the BCC, the
processing at transmitter side can be relieved.
Also, if the compare system is used, the same transmitted sentences of plural quantity (3
formats or more) should be sent.
CPU board(DIPSW for setting)
DIPSW for setting
DIPSW8 for setting the
error check
