Mindeo ES4200, Руководство пользователя

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scanner responses NAK.
The scanner’s response to this command is PARAM_SEND, not ACK. Depending on the time-out setting,
and the number of parameters requested, this reply may fall outside the programmable Host Serial
Response Time-out. If this occurs, this is not a time-out error. To compensate, increase the time-out.
Scanner Requirements
When the scanner receives this message, it processes the information by formatting a PARAM_SEND
message containing all requested parameters supported and their values. The programmable Host
Serial Response Time-out can be exceeded when processing this message, depending on the time-out
set and the number of parameters requested.
For example: the value of scanner parameter “0301” is 1, when host query information of the parameter
“0301”, the PARAM-REQUEST sent by host is as following:
Length Opcode Status Parameter code Checksum
0x07
0x3F
(‘?’)
0x80
0x30 0x33 0x30 0x31
(‘0’ ‘3’ ‘0’ ‘1’)
0xFE 0x76
the PARAM-SEND responded by scanner is as following:
Length Opcode Status Parameter code Data type parameter Checksum
0x0A
0x23
(‘#’)
0x00
0x30 0x33 0x30 0x31
(‘0’ ‘3’ ‘0’ ‘1’)
0x44
‘D’
0x30 0x31
(‘0’ ‘1’)
0xFE 0x6A