April 09, 2012How to make my 16-bit app 'play nice' under XP?
Hello, I am developing a 16-bit DOS helper application that works with a 32-bit Windows console application. The function of the 16-bit app is to access emulated features of ntvdm that 32-bit console apps (so far as I can tell) do not have access to, specifically blinking text and full-screen 40-column text mode. The 32-bit console app does the network communication required that 16-bit DOS programs (so far as I can tell) do not have access to under NTVDM. While the 16-bit helper program works fine, it has a busywaiting problem. While waiting for instructions from the 32-bit console app, it uses >95% CPU. There are several documented interrupts for DOS programs to call when they are idle, but none of them seem to do the trick to tell WINXP that the program is idle. I've tried INT 28h and Int 2Fh function 16h subfuction 80h. Neither reduces the CPU usage of my program. Any ideas?