VGA over IO Board - sync based on speed?
Posted: Fri Jul 31, 2020 11:36 pm
I'm trying to get this working on a CRT VGA monitor, and I've noticed something weird.
If I use vga_scaler it looks like crap. If I disable it, it appears to be displaying at native resolutions, but the image is unstable.
What's extra weird, is the stability of the image is based on what speed I'm running it at. In MS-DOS at the lowest speed, I get an "OUT OF RANGE H: 18.7Khz V:35.8Hz" warning. As I increase the speed, the image gradually becomes more and more stable, with it being the most stable (but not quite perfect) at 100Mhz.
Any ideas? Running to a Dell E772c using the Analog IO Board via VGA. Using the latest cache 29.
If I use vga_scaler it looks like crap. If I disable it, it appears to be displaying at native resolutions, but the image is unstable.
What's extra weird, is the stability of the image is based on what speed I'm running it at. In MS-DOS at the lowest speed, I get an "OUT OF RANGE H: 18.7Khz V:35.8Hz" warning. As I increase the speed, the image gradually becomes more and more stable, with it being the most stable (but not quite perfect) at 100Mhz.
Any ideas? Running to a Dell E772c using the Analog IO Board via VGA. Using the latest cache 29.