DL8000 Preset Instruction Manual
D-74
Communications Protocols
Revised February-2016
specifies four registers (100, 101, 102, and 103) that are mapped to a
group of analog input (AIN) values in engineering units (EU) starting at
the analog input in the fourth module location, first position (4-1), such
that:
Register 100 = EU of AIN point in location 4-1.
Register 101 = EU of AIN point in location 4-2.
Register 102 = EU of AIN point in location 4-3.
Register 103 = EU of AIN point in location 4-4.
With
Parameter Indexing
the configuration of:
Starting Register
Ending Register
Device Parameter(s)
Indexing
Conversion
109
114
FST 1,R1
Parameter
1
specifies six registers (109, 110, 111, 112, 113, and 114) that are
mapped to a group of FST 1 parameters starting at FST Register 1, such
that:
Modbus Register 109 = Register 1 of FST Point Number 1.
Modbus Register 110 = Register 2 of FST Point Number 1.
Modbus Register 111 = Register 3 of FST Point Number 1.
Modbus Register 112 = Register 4 of FST Point Number 1.
Modbus Register 113 = Register 5 of FST Point Number 1.
Modbus Register 114 = Register 6 of FST Point Number 1.
Conversion Code 1 (Float to Integer, Float Scale 1) converts the floating
point value to an integer before the response message returns to the host.
Once you map a register, any Modbus request can reference it,
providing the TLP’s data type is appropriate for the function code.
Note
:
If the native data type does not meet the requirements of the
Modbus Host device, conversion codes are available to convert
the data to the required data type. For the
DL8000
, you can
select to have the mapping apply to all communication ports or
on a selected port only.
When the system receives a Modbus request, it searches for the
referenced register(s). If it finds a matching register number, the system
builds a response based on the device point type and parameter
configured in the table. If the system cannot find a register number
match, it returns an error message.
A DL8000 has 24 available register tables, each table containing 15
entries.
You use either point indexing or parameter indexing to define multiple
registers for each table entry. By making the registers continuous (where
the Start Register address of a new line is one greater than the End
Register address of the previous line), you can create a continuous data
