I have a program written for R14 using ADS/ARX and I would like to add serial port communications in order to be able to collect data inside of AutoCad. Iused to use the Greenleaf Comm libraries under DOS, but Greenfeaf is not familiar with any of the AutoCad development systems and they are unable to advise me if any of their products will work, especially under R14. Has anyone been able to implement interrupt driven serial communications under ADS/ARX ? I'm using visual C++, version 4.2b. Thanks.