The setup on the earlier monitors was sometimes call “ODB” , don‘t know why. Was equivalent to setup.
Sent from my iPhone > On May 20, 2024, at 11:02, Wayne S <wayne.su...@hotmail.com> wrote: > > In the vt100, setup menu “B” had an interlace on or off setting. > I just looked it up. > > > Sent from my iPhone > >> On May 20, 2024, at 10:51, Paul Koning via cctalk <cctalk@classiccmp.org> >> wrote: >> >> >> >>>> On May 20, 2024, at 1:37 PM, Wayne S via cctalk <cctalk@classiccmp.org> >>>> wrote: >>> >>> Young , hah. No i’m old 70. >>> The pc monitors, not Tv, always had a setup menu. Even the Vt100 series let >>> you choose interlace if you needed. >> >> VT100? I don't think so. And yes, it has a setup menu, but that's setup of >> the terminal functionality, not the monitor part. >> >> The earliest monitors could only handle one format. A major innovation was >> "multisync" where the monitor would determine the horizontal and vertical >> sweep rate and line count, and display things the right way. The first PC I >> owned had one of those, and as far as I can remember it had nothing that one >> would call a "setup menu". >> >> The reason interlace matters is not the very slight slope of the scan line >> in analog monitors, but rather the fact that alternate frames are offset by >> half the line spacing of the basic frame, so each frame sweeps out the gaps >> in between the lines scanned by the preceding frame. It matters to get that >> right, otherwise you're not correctly displaying consecutive rows of pixels. >> In particular, when doing scan conversion (from analog format to a digital >> X/Y pixel raster) you have to offset Y by one every other frame if interlace >> is used, but not if it isn't. >> >> paul >> >>
