NEC RS-232C user manual Check code, Header Message, Delimiter

Models: RS-232C

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4.5 Check code

Message format of the “Set parameter” is as follows,

STX

OP code

OP

code

Set

Value

 

ETX

 

page

 

 

Hi

 

Lo

Hi

 

Lo

MSB

 

 

 

LSB

 

Refer to section 5.3 “Set parameter” for more details.

4Set Parameter reply

 

The monitor replies with this message for a confirmation of the “Set parameter message”.

 

 

 

 

Message format of the

“Set parameter reply” is as follows,

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

STX

 

Result

OP code

OP code

 

Type

 

Max value

Requested setting

ETX

 

 

page

 

 

 

Value

 

 

 

Hi

Lo

Hi

 

Lo

Hi

 

Lo

Hi

 

Lo

MSB

 

 

 

LSB

MSB

 

 

LSB

 

Refer to section 5.4 “Set parameter reply” for more details.

5Command

“Command message” format depends on each command.

Usually, this “command message” is used for some non-slider controls and some special operations, such as “Save current settings”, “Get timing report”, “power control”, “Schedule”, etc. Refer to section 5.5 “Commands message” for more details.

6Command reply

The monitor replies to a query from the controller.

“Command reply message” format depends on each command. Refer to section 5.5 “Commands message” for more details.

4.5 Check code

Header Message

Check code

Delimiter

Check code is the Block Check Code (BCC) between the Header and the End of Message except SOH.

 

SOH

 

D0

27

26

25

24

23

22

21

20

 

 

 

 

 

 

 

 

 

 

 

Reserved

 

 

D1

 

 

 

 

 

 

 

 

 

 

Destination

 

D2

 

 

 

 

 

 

 

 

 

Source

 

D3

 

 

 

 

 

 

 

 

 

Type

 

D4

 

 

 

 

 

 

 

 

 

Length(H)

 

D5

 

 

 

 

 

 

 

 

 

Length(L)

 

D6

 

 

 

 

 

 

 

 

 

STX

 

D7

 

 

 

 

 

 

 

 

 

Data

 

 

D8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ETX

 

Dn

 

 

 

 

 

 

 

 

 

Check code

 

Dn+1

P

P

P

P

P

P

P

P

Dn+1 = D1 XOR D2 XOR D3 XOR ,,, Dn

XOR: Exclusive OR

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NEC RS-232C user manual Check code, Header Message, Delimiter