Moxa MPC-2150Z-T [53/65] Idchk inverse data checksum

MPC-2150 Hardware Display Control Interface

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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).

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

message that the checksum has failed with the attention code set to NAK.

Downloading RGB Files

Use the following commands for downloading RGB files.

Commands Description

DL? Data: none (0 byte)

ACK: Total packet numbers (1 byte)

DLN Data: Appointed packet (1 byte)

ACK: File content (30 bytes maximum, except for the last packet)

The command DL? will send a request to the micro controller and ask how many packets that need to be

downloaded. The reply from the micro controller shall be used when using the command DLN to download the

specific packets. Refer to the following section for detailed descriptions of the DL? and DLN.

Command DL?

Byte No. Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6

Hex 0x7 0xFF 0x44 0x4C 0x3F 0x0 0x2A

ASCII D L ?

Command DLN

Byte No. Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Byte 8

Hex 0x7 0xFF 0x44 0x4C 0x4E 0x1 0x1A 0x50 0xAF

ASCII D L N

Here is the example of downloading the RGB file package 0:

Command to read package 0.

0x07 0xFF 0x44 0x4C 0x4E 0x01 0x1A 0x00 0xFF

ACK the package 0 of the first RGB file

0x06 0xFF 0x44 0x4C 0x4E 0x20 0xFC 0x00 - Data IDCHK

Data should be the real value of the RGB file package 0.