Chino KP3000 User Manual

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<Table 2. Function code table>
Code Function Unit
MODBUS original function
(Reference)
02
Reads digital input data 1 bit
Reads input relay status
03
Reads analog setting value 16 bits
Reads the contents of maintenance
register
04
Reads analog input data 16 bits Reads the contents of input register
06
Writes the analog setting value 16 bits Writes to single maintenance register
08
Loop back test (Sends the received
data)
Loop back test
16
Writes multiple analog setting
values
Writes to multiple maintenance
registers
8-3-3. Data division
Function of data differs depending on the function code. During the request from the master, it
consists of code number (relative number calculated from reference number mentioned hereinafter)
of the data that is to be read and written and the data unit count etc. Response from the slave is made
up of data etc. that is requested.
Basic data of MODBUS is 16 bit integer on a whole and presence or absence of tag is specified for
each data. Thus by putting the decimal point after another number make it as an integer value or by
fixing the decimal point position make it standard by upper and lower limit of the scale and express it.
In KP, a system of putting the decimal point in a different position is fetched.
8-3-4. Reference number
In the KP, there is a number called 'Reference number' that is allotted and it is required when
reading and writing the data. KP is categorized depending on its type, into 'Digital input data', 'analog
input data' and 'analog settings value'. Number in the message is specified by “relative number”
which is corresponding with each reference number.
<Table 3. Reference number and relative number>
Data kind Reference
number
Relative number MODBUS original
(Reference)
Digital input data
10001 to 20000
Reference
number-10001
Input relay
Analog input data
30001 to 40000
Reference
number-30001
Input register
Analog setting value
40001 to 50000
Reference
number-40001
Maintenance register
Example) Relative number of execution SV of 'Reference number 30109' is '108'.
In the data division, specific numeric value can be assigned as error data, like input data. When
using such data, first judge the error of the data and then combine it with decimal point data.
If it is combined with decimal data earlier, then error data is mistook as normal data.
Precautions

Chino KP3000 Specifications

General

Brand	Chino
Model	KP3000
Category	Controller
Language	English