Moxa Technologies IA5150 - Manual (Page 85)

NPort IA5150/5250 Series User’s Manual Configuring NPort Administrator
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function, the NPort driver will keep querying NPort’s firmware several times to make
sure there is really no data queued in the NPort firmware buffer, rather than just flushing
the local buffer. This kind of design is used because of some special considerations.
However, it might take more time (on the order of several hundred milliseconds) than a
native COM1, because it needs to work via Ethernet. That’s why the native COM ports
on the motherboard can work fast with this function call, but NPort requires much more
time. In order to accommodate other applications that require a faster response time, the
new NPort driver implements a new “Fast Flush” option. Note that by default, this
function is disabled.
• To begin with, make sure there are some “PurgeComm()” functions being used in your
application program. In this kind of situation, you might find that your NPort exhibits a
much poorer operation performance than when using the native COM1 port. Once you
have enabled the “Fast Flush” function, you can check to see if there has been an
improvement in performance.
• By default, the optional “Fast Flush” function is disabled. If you would like to enable this
function, from the “NPort Administrator,” double click on the COM ports that are
mapped to the NPort, and then select the “Fast Flush” checkbox. You should find that
when “Fast Flush” is enabled, the NPort driver will work faster with “PurgeComm().”
8. The Serial Parameter settings shown here are the default settings when the NPort
IA5150/5250 is powered on. However, the program can redefine the serial parameters to
different values after the program opens the port via Win 32 API.