Mindeo FS580, Руководство пользователя

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For example: Scanner sends NAK.
Length Opcode Status Cause Checksum
0x04 0x4E 0x00
0x40
(the parameter requested is not exist)
0xFF 0x6E
Table 5-4 describes NAK types supported by the scanner.
Table 4-5 Scanner-supported NAK types
NAK Type Meaning Receiver Action
NAK_OVERFLOW Data Overflow
While receiving message with the baud rate
115200B/s, scanners receive buffer may occur
overflow. If the message length is greater than
7, the scanner fails to receive and process the
data without delay, and reply NAK_OVERFLOW
to host.
NAK_RESEND Checksum incorrect.
Ensure checksum is correct. Send packet again
with resend bit set (with the retransmit status bit
set).
NAK_BAD_CONTEXT
The parameter want to be changed
do not exist
Do not send the same message again. Ensure
the correct message is sent.
NAK_DENIED
The parameter want to be changed
exceeds the range
NAK_NO_PARA
Host does not recognize the
command.
NAK_OUT_OF_RANGE
Host is unable to comply with the
requested command (e.g., scan
mode setting code is out of range).