Modbus – IAI America ROBO Cylinder Series User Manual

Page 110

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5. Modbus RTU

102

Modbus

(4) Query sample

A sample query that reads the deviation monitor (from address 900E

H

) of a controller of axis No. 0

is shown below.

z

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

01 03 90 0E 00 02 88 C8

Field

RTU mode

8-bit data

Start

Silent interval

Slave address [H]

01

Function code [H]

03

Start address [H]

900E

Number of registers [H] 0002

Error check [H]

88C8 (in accordance with

CRC calculation)

End

Silent interval

The response to the query is as follows.

z

Response (silent intervals are inserted before and after the response)

01 03 04 00 00 00 0B BB F4

Field

RTU mode

8-bit data

Start

Silent interval

Slave address [H]

01

Function code [H]

03

Number of data bytes [H] 04 (4 bytes = 2 registers)

Data 1 [H]

00 00 00 0B

Error check [H]

BBF4 (in accordance with CRC calculation)

End

Silent interval

The deviation monitor is “0000000B” o Convert into decimal number o 11

The deviation over a 1-ms period between the position command value and the feedback

value (actual position) is 11 pulses.

Note The data of the response example is simply an example and will vary depending on

various conditions.

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