ICP DAS USA I-7521 User Manual page 41

[Timeout]
The $AAJN[timeout] command is only supported by firmware version 3.0 and
above.
If the length of a command or response string is too long, or the data
transmission time between the I-752N and peripheral RS-485 devices/RS-232
device is too long, the timeout value can be adjusted to ensure the amount of full
data is received.
If the timeout value for the RS-232 COM Port is too small, the response part will
be received by the 1K byte Queue buffer for RS-232 Ports.
The $AAU command can be used to read the buffer.
Note: More information about the timeout command can be found in Sec.
5.3.33.
[Summary]
COM Ports receive data based CrLfmode rules.
Each port has its own data format, timeout values and CrLfmode. Setting correct
parameters will ensure that the COM Ports work well and efficiently.
[Command and Response Flow Chart]
I-7521/I-7522/I-7522A/I-7523/I-7524/I-7527 User's Manual,Ver2.5 Aug.2015
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