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G5 Weighing Instrument
4-1
4. Output Data
Output data mapping is shown in the table below. Output data is 8 bytes as described
in table below. Data direction is from network (PLC) to G5 Instrument.
Byte Size Description
0 – 1 2 Command
2 – 3 2 Parameter ID
4 – 7 4 Data to write
Command
Bytes 0 - 1: The command byte is used when writing data to the instrument and to
issue various scale related commands such as taring, zeroing etc.
Note that a new command is detected when the content of the command register is
changed. If the same command shall be issued again, the command byte must first be
set to 0 and this should be verified by reading command acknowledge. Then the
desired command may be issued.
The response to a given command is the ‘Command acknowledge’ and the
‘Command error’ bytes in the input data of the connection.
Parameter ID
Bytes 2 - 3: The selected Level (1 - 4) or Setpoint (1 - 4) to set. The data in byte 2 and
3 are ignored for any other commands than 221 and 222.
Data to write
Bytes 4 to 7: The value of the Preset tare, Level, Setpoint, Digital outputs or Analog
Output to set. Note that the format of the value should be floating point or integer
depending on the
Data Format parameter. The data in bytes 4 to 7 are ignored for any
other commands than 200, 201, 220 – 222. No of decimals in an integer value is
according to the weight and flow rate set-up. Analog output (command 200) is always 3
decimals.
Example: A value with 3 decimals e.g. 7.234 should be written as 7234 to the
bytes 4 – 7.
Byte order
The byte order in multi byte values (more than one byte) is depending on the type of
fieldbus used.
Profibus DP: MSB first (Most Significant Byte first).
DeviceNet: MSB first.
ControlNet: MSB first.
EtherNet/IP: LSB first (Least Significant Byte first).