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Question When I install NPort Real COM driver, I see a "Fast Flush" option, what does it mean?
Question Type Application
Updated 4/1/2008 4:03:26 PM
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Products NPort 5230 Series,NPort Express DE-211,NPort Express DE-311,NPort 5210/NPort 5230/NPort 5232 Series,NPort 5410/NPort 5430/NPort 5450 Series,NPort 5430 Series,NPort 5610/NPort 5630 Series,NPort Server Lite DE-301/302/304/331/332/334,NPort DE-311M


1. Fast Flush :

You can make sure that there are some Win32 "PurgeComm()" functions being used in your application program. You also find NPort gets much poorer performance than native COM1 in operation. Then, you can try to enable this option to check if this status can be improved.

2. How to work?

In some applications, the user's program will use Win32 "PurgeComm()" function before it reads or writes data. In our design, after the program uses this PurgeComm() function, the NPort driver will keep querying NPort's firmware several times to make sure there is really no data queuing in NPort firmware's buffer, rather than just flushing local buffer only. This design is due to some special consideration. However, it might take more time (about several hundred milliseconds) than native COM1 because it needs to work via Ethernet. That's why the native COM ports on motherboard can work faster with this function call, but NPort needs much more time to make it. In order to fit some other applications that require to speed up the response time, we implement a new "Fast Flush" option in the new NPort driver now. By default, this function is disabled.

* This function is just for NPort Management Suite v3.2 above or NPort Administrator Suite v1.2 above.

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