beautypg.com

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

Page 33

background image

30

Operation Method

RS485 Communication Function


4.4 Reply Message Structures

4.4.1 Reply Messages to Read Request Messages

S

T

X



A

C

K









E

T

X

B

C
C


4.4.2 Reply Messages to Write Request/Storage Request Messages

S

T

X



A

C

K

E

T

X

B

C
C


4.4.3 Reply Messages In Case of an Error

S
T
X



N
A
K


E
T
X

B
C
C

Start

code

Address

Identifier

Numeric

data

End

code

BCC

data

Acknowledgement
code

⑧ ⑥

Start

code

Address

End

code

BCC

data

Acknowledgement
code

Start

code

Address

End

code

BCC

data

Negative
acknowledgement
code

ERR

type