Stupid eBay user du jor

Well, depending on the "dumbness" of the program doing the refreshing it can vary pretty wildly. When I was doing the software for the "plug this card into your PC in place of the normal MDA and drive your VT-100 (or 220) with it, it was actually pretty surprising how well a VT220 at 19200 could keep up with a monochrome 80x25 display. All it took was a sufficient amount of processing horsepower at the adapter end to make determinations of what was going on and issuing the proper ANSI escape sequences. We had a threshold that once exceeded determined that it was faster to clear the display and repaint it than send out all of the "move to (X,Y), clear to end of line, etc." sequences. Out of curiosity, I kept a counter that recorded how many times in a session that actually occured. It wasn't very often--and typically coincided with an application clearing the screen. Detecting scrolling activity was a bit tricky. You couldn't hook the BIOS routine to do it, because very few full-screen programs (like Lotus 1-2-3) actually used the BIOS routines and in between samples, the screen may have scrolled several lines. I've sometimes wondered if much of Windows couldn't have been simplified with a dedicated processor to track the contents of the various windowed information instead of having the application redraw it all of the time. Cheers, Chuck