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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

4.2 Message Types

Message types include transmission request messages from the host computer and transmission

reply messages from this unit.

All codes from STY, address, request, identifier to ETX (except BCC) are represented by ASCII

codes.

4.3 Request Message Structures (transmission from the host computer to the unit)

4.3.1 Structure of Read Request Messages

S

T

X



R




E

T

X

B

C
C


4.3.2 Structure of Write Request Messages

S

T

X



W









E

T

X

B

C
C


4.3.3 Structure of Storage Request Messages

S

T

X



W




E

T

X

B

C
C


Start

code

Address

Request

(read)

Identifier

-

End

code

BCC

data

Start

code

Address

Request

(write)

Identifier

Numeric

data

End

code

BCC

data

Start

code

Address

Request

(write)

Identifier

-

End

code

BCC

data