Moxa MD-119-X1 [37/44] Cmd message commands and queries

MD-119 HW Manual Display UART Command

C-3

CMD (Message Commands and Queries)

The command can be one of the following values:

CMD 0 CMD 1 CMD 2 ASCII Description

0x42 0x4C

0x49

“BLI”

Brightness Control

0x45 0x54 0x43 “ETC”

Elapsed Time Counter Query

0x44 0x53 0x54 “DST”

Display State

0x4D 0x41 0x4E “MAN”

Manufacturer ID Code

0x4D 0x43 0x43 “MCC”

OSD Control

0x50 0x4F 0x54 “POT”

Potentiometer Control

0x53 0x4E 0x42 “SNB”

Serial Number Query

0x53 0x57 0x49 “SWI”

Software Version Query

0x54 0x59 0x50 “TYP”

Type/Model Number Query

0x56 0x45 0x52 “VER”

ID Version Number Query

LEN (Data Length)

This byte defines the length of data in the message in bytes. The maximal value for this field is 74 bytes, and

the minimal value is 0 byte.

IHCHK (Inverse Header Checksum)

This is a simple 8-bit checksum of the header data, message bytes 0 to 5 on which a bit-wise inversion has been

performed. The checksum should be initialized to 0. The 8-bit sum (without carry) of bytes 0, 1, 2, 3, 4, 5, and

6 shall be 0xFF.

If a message is received with an incorrect checksum, the display will replay with the attention code set to NAK

and no data field. This does not apply to Broadcast messages in RS-485 mode, in which case there will be no

reply.

DATA (Data Field)

The data field shall only be transmitted if LEN is larger than 0. This field depends on the CMD transmitted.

IDCHK (Inverse Data Checksum)

These bytes shall be only transmitted if LEN is larger than 0. This is a simple 8-bit checksum of the data field,

message bytes 7 to 7+(LEN-1) on which a bit-wise inversion has been performed. The checksum shall be

initialized to 0. The 8-bit sum (without carry) of bytes 7 through 7+LEN inclusive shall be 0xFF. The receiver will