BLN nobel G5, Technical Manual

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G5 Weighing Instrument
6-23
Supported Modbus functions
Function Description
01
Read Coil Status
Reads the state of discrete outputs (0X references, coils).
Only implemented because some 'masters' use this function
to initiate communication.
Coil range: 1 – 16 (Max number of points to read: 16).
Response: Zero (OFF) for all requested points.
02
Read Input Status
Reads the state of discrete inputs (1X references).
This function is implemented only because some 'masters' use
this function to initiate communication.
Input range: 1 – 16 (Max number of points to read: 16).
Response: Zero (OFF) for all requested points.
03
Read Holding Reg.
Reads the binary contents of holding registers (4X references).
Max number of registers to read: 125
05
Force Single Coil
Forces a single coil (0X references) to either ON or OFF.
This function is used to activate commands in the instrument.
06
Preset Single Reg.
Presets a value into a single holding register (4X references).
08
Diagnostics
This function can provide a series of different communication tests,
depending on a sub function code. The instrument supports only
sub function code 00, which is a 'loop-back' test. The same data as
received will be sent back to the master.
Max number of data bytes: 64
15
Force Multiple Coils
Forces each coil (0X references) in a sequence of coils to
either ON or OFF. This function is used to activate commands
in the instrument.
Max. number of points: 16 (only the first is used).
16
Preset Multiple reg.
Presets values into a sequence of holding registers (4X references).
Max number of registers to preset: 125
Note: No broadcast messages are allowed.
It is possible to send or fetch any number of registers (max 125) or I/O bits (max. 16).
If the master tries to read more registers than there are available, the instrument will
send dummy values for those registers not available.