Symbol SE 923, Integration Manual

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SE-923 Scan Engine Integration Guide
requested, this reply may fall outside the programmable Serial
Response Time-out. It should not be considered an error if the time-
out is exceeded. To compensate, increase the time-out.
Decoder Requirements
When the decoder receives this message, it processes the information by formatting a
PARAM_SEND message containing all requested parameters that are supported, and their
values. The programmable Serial Response Time-out may be exceeded when processing this
message, depending on the time-out set, and the number of parameters requested.
Hints for requesting parameter values:
Before forming a PARAM_REQUEST, be sure you are requesting parameters supported by
the decoder (Table 6-7). To find out what parameters are supported, send an 0xFE (request
all parameters). The response to this is a PARAM_SEND which contains all the supported
parameters and their values.
When using the 0xFE, it must be in the first position of the request_data field, or it is treated
as an unsupported parameter.
Unsupported parameters are not listed in the PARAM_SEND response. Requesting
unsupported parameters has no effect, but can cause delays in responding to requests for
valid parameters. See Table 6-8 for example requests and responses.
Table 6-7. Example of Supported Parameter Numbers
Supported Parameter Number Associated Parameter Values
01 00
02 01
9C 07
E6 63
Table 6-8. Example Requests and Replies
PARAM_REQUEST message Response PARAM_SEND message
#ALL 05 C7 04 00 FE FE 32 0D C6 00 00 FF 01 00 02 01 9C 07 E6 63 FC 3E
#1, 9C 06 C7 04 00 01 9C FE 92 09 C6 00 00 FF 01 00 9C 07 FD 8E