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Operation method, Rs485 communication function – Yamato Scientific BB600 Low Constant Temperature Water Bath User Manual

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Operation Method

RS485 Communication Function

5.2 Write communication example

Example) Request message:
A request for setting "SV to 135" (writing 135) is transmitted to the unit set at address 03.
Reply message from the unit to this request message: Information that the request message has
been received is returned.

Confirm that the data has been properly written by reading it separately.






S

T

X

0

3

A

C

K

E

T

X

B

C
C


Code Symbol/Data

ASCII

code

*2

Start Code

STX 02H

Address

03

30H 33H

Request (Write)

W 57H

Identifier

*1

PV1

53H 56H 31H

Numeric Data

00135

30H 30H 31H 33H 35H

End Code

ETX 03H

Request

56H

BCC data

Reply

04H

Acknowledgement code

ACK 06H

*1): See "7. List of Identifiers/Commands."
*2): For ASCII codes, see "8. List of ASCII Codes."

S

T

X

0

3

W

S

V

1

0

0

1

3

5

E

T

X

B

C
C

Write request message

(transmitted from the host computer)

Reply message (returned from the unit)