NEC RS-232C user manual Message type, Get current Parameter from a monitor

5. Message type

5.1 Get current Parameter from a monitor.

STX

OP code page

OP code

ETX

Hi

Lo

Hi

Lo

1st

2nd

-3rd

4th

–5th

6th

Send this message when you want to get the status of a monitor.

For the status that you want to get, specify the “OP code page” the “OP code”, refer to

“Appendix

A. Operation code table”.

1stbyte) STX: Start of Message

ASCII STX (02h)

2nd-3rdbytes) OP code page: Operation code page.

Specify the “OP code page” for the control which you want to get the status.

Refer to “Appendix A Operation code table” for each item.

OP code page data must be encoded to ASCII characters.

Ex.) The byte data 02h must be encoded to ASCII characters '0' and '2' (30h and 32h).

OP code page 02h -> OP code page (Hi) = ASCII '0' (30h)

OP code page (Lo) = ASCII '2' (32h)

Refer to Operation code table. (Appendix A)

4th–5thbytes) OP code: Operation code

Refer to “Appendix A Operation code table” for each item.

OP code data must be encoded to ASCII characters.

Ex.) The byte data 3Ah must be encoded to ASCII characters '3' and 'A' (33h and 41h).

OP code 3Ah ->

OP code (Hi) = ASCII '3' (33h)

OP code (Lo) = ASCII 'A' (41h)

Refer to Operation code table.

6thbyte) ETX: End of Message

ASCII ETX (03h)

5.2 "Get parameter" reply

STX

Result

OP code page

OP code

Type

Max value

Current Value

ETX

Hi

Lo

Hi

Lo

Hi

Lo

Hi

Lo

MSB

LSB

MSB

LSB

1st

2nd-3rd

4th–5th

6th

–7th

8th

-9th

10th -13th

14th -17th

18th

The monitor replies with a current value and the status of the requested item (operation code).

1stbyte) STX: Start of Message

ASCII STX (02h)

2nd-3rdbytes) Result code.

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