Hi,

I have a gizmo attached on serial port and need to detect
changes of controls signals DSR, DTR etc. no data, just
changes (edge). I do it with MSCOMM.ocx and it works,
but only when is CPU on idle and windows messages are
delivered on time. When is load over 20% timing of the
messages sent is broken and can't be decoded properly.

Please let me know with any idea how to tap serial's driver's
IRQ via callback.

Thank you,

VIeditorlover

MS-Windows is not a real-time operating system, so no matter what you try the signals might or might not arrive to your program on time. You might try the Communications Resources link

Spot on and sorry for late reply

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