Our 32 bit application relies on a 3rd party 32 bit DLL COMM Port driver (via external function calls) to communicate with various scientific instruments.  The code pattern is a DO Loop making function calls and waiting. This code is embedded into device specific user object functions. (Not OO code)  Our code is tightly coupled to this driver API

Our application code is fully ported and tested  in 64 bit with the exception of this feature set.  The hold up is that the COMM driver vendor is out of business.,  There will never be a 64 bit version.

We looked at OCX solutions.  All of them supply event handlers that an app codes to respond to input buffer or signal line changes. Here are a couple of examples

https://www.fabulatech.com/serial-port-control-api/ax-Control.html

http://www.comm32.com/index.html

The bigger challange is what to do for 64 bit.  The PB IDE only supports Event coding for 32 bit OCX controls!  For 64 bit the OCX must be dynamically loaded.  There is no place to write an event handler for a generic OLEControl!

Do you have any concrete suggestions on how to proceed?  Know of a control that might might?

Thanks for sharing