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Topic:   .Input method hangs the application when using USB/422/485 device

By: JorgePosted on: Sep 20 2017 at 01:56:52 PM
When operating with wired 422/usb converters, InBufferSize cannot exceed 5462 bytes. 5463 hangs the application on calling SComm.input. If a 422/blue tooth converter is used, the 5462 byte threshold does not apply. Tested with a buffer size of 15000 with no problem.
Suggest you include it in the specs of SComm
MSComm does not have this limitation.

By: SupportPosted on: Sep 29 2017 at 06:01:19 PM
I was able to reproduce the problem using a starttech USB/422/485 device. I wasn't able to reproduce it with any other devices.

So it seems to be related to a specific device chipset.

The problem appears when InbufferSize or OutbufferSize is set to an odd number. Seems the device doesn't like odd numbers.

I think we need some more testing and we'll release an update that avoids the problem. This update will be released soon. In the meantime just set both buffers, InbufferSize and OutbufferSize to even numbers, for example 4096, 8192, 16384 etc and the problem goes away.

Thank yuou Jorge for sending your sample project that helped to reproduce/diagnose the problem.

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Topic:- .Input method hangs the application when using USB/422/485 device


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