Mindeo FS580, Руководство пользователя

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5-7 REQUEST_REVISION
Description: Request the software revision string from the scanner
Packet Format
Length Opcode Status Checksum
0x03 0x56
Field Descriptions
Field Name Format Size Description
Length 0x03 1 Byte Length Field
Opcode 0x56 1 Byte
Identifies this opcode type.
Status
Bit 0: Identifies transmit status
Bit 6-1: Unused
Bit 7: Command source
1 Byte
Bit 0:
0=First time packet is sent
1= Subsequent transmission
attempts
Bit 7: always be 1(message is from
the host)
All unused bits recommend to be set
to 0.
Checksum
2's complement sum of message contents
excluding checksum.
2 Bytes Checksum of message.
For example:
Length Opcode Status Checksum
0x03 0x56 0x80 0xFF 0x27
Host Requirements
The host sends this message to request revision information from the scanner. The scanner responds
with REPLY_REVISION.
Scanner Requirements
The scanner sends its revision string to the host. See
“ 5-8 REPLY_REVISION ” .