Instruction Manual

5. Modbus RTU

141

Modbus

(4) Query sample

A sample query that moves a controller of axis No. 0 to start position 2 is shown below.

An example of start position setting.

Fig. 5.2

Query (silent intervals are inserted before and after the query)

First time 01 05 04 1D 00 00 5C FC --- Write 0000

to set the edge

Second time 01 05 04 1D FF 00 1D 0C --- Movement command

Field RTU mode

8-bit data

Start Silent interval

Slave address [H] 01

Function code [H] 05

Start address [H] 041D

Changed data [H] First time: 0000

Second time: FF00

Error check [H] First time: 5CFC

(in accordance with CRC

calculation)

Second time: 1D0C

(in accordance with CRC

calculation)

End Silent interval

If the change is successful, the response message will be the same as the query.

(5) Start address

Address Symbol Name Function

0418 ST7 Start position 7 Move to position 7

0419 ST6 Start position 6 Move to position 6

041A ST5 Start position 5 Move to position 5

041B ST4 Start position 4 Move to position 4

041C ST3 Start position 3 Move to position 3

041D ST2 Start position 2 Move to position 2

041E ST1 Start position 1 Move to position 1

041F ST0 Start position 0 Move to position 0