> On May 20, 2024, at 3:40 PM, Adrian Godwin via cctalk <[email protected]>
> wrote:
>
> I remember the VT100 interlace setting. Yes, it changed the signal
> generated. I don't know if it also changed the characteristics of the
> monitor but I would think not.
The Pro also has such a thing in its video card. It doesn't touch the monitor
as far as I can tell. The details may in the video gate array spec (I have
that on paper, buried somewhere); my guess would be that it changes the
vertical sync frequency from horizontal rate / 262 to horizontal rate / 262.5.
> It gave slightly higher resolution (the expectation would be double but the
> tube didn't have focus that good) at the cost of a horrible juddering
> display. I don't remember it being there on the later VT220.
Yes, that's just how I remember it on the Pro.
The Pro has another display feature: you can set it to 625 lines at 25 Hz (or
half that at 50 Hz). The US monitor handles that, somewhat to my surprise, but
it's not a pleasant experience.
paul
