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FI-521 User Manual
6 Serial Communication
6.1 Com Port 1
COM1 is a RS-232 bi-directional port. See the service manual for connection details.
6.2 Com Port 2
COM2 can be RS-232 or RS-485. See the service manual for connection details.
6.3 Protocol
The baud rate and byte format is set by USER>COM1/2>BAUD.RT and USER>COM1/
2>BYT.FMT.
Responses to serial commands will be immediate or within one force measure cycle of
the indicator. One second should be adequate for use as a time-out value by a remote
(controlling) device.
6.4 Transaction String
The length of each item in a transition string:
l
Reading data --- 6 bytes
l
Data polarity ----1 byte: "-" for negative, and followed the first digit; " " for
positive.
l
Decimal point ---1 byte: "."
l
Measure unit ----1-3 bytes:" lbf"," kgf","N”. Units are always lower case and
left aligned
l
Current status-- 4 bytes
m
If the force is over capacity, the indicator will return eight "^" characters
(the field of polarity, decimal point, force data is filled by "^").
m
If the force is under capacity, the indicator will return eight "_" characters
(the field of polarity, decimal point, and weight data is filled by "_").
m
If the zero point is error, it will return eight "-" characters (the field of
polarity, decimal point, and weight data is filled by "-").
Useless leading 0 before digits is suppressed, reading force is right aligned.
Table 6.1 Symbols Used
<LF>
Line Feed character (hex 0AH)
<CR>
Carriage Return character (hex 0DH)
<ETX>
End of Text character (hex 03H)
<SP>
Space (hex 20H)
H
1
H
2
H
3
H
4
Four current status bytes
