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monotech / NuXT

MicroATX Turbo XT Motherboard, with VGA, Floppy, CF, Serial
GNU General Public License v3.0
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CGA cold boot #5

Open eltair opened 5 years ago

eltair commented 5 years ago

Cold booting the machine with the onboard VGA disabled and an IBM CGA card, no output is displayed on the monitor. If I wait a bit and reset, the machine boots correctly with CGA output. If I try to reset too quickly I get no output, so maybe the CGA card just hasn't had enough time to initialize?

skiselev commented 5 years ago

Weird. I've actually tested my Micro 8088 (not a NuXT) with CGA, and it works properly as long as I have the DIP switches set correctly. If the switches are not set correctly, for example they set to "VGA/EGA/None" instead of CGA 40x25 or CGA 80x25, it will show garbled text on the screen. Not sure the on-board VGA (although disabled) somehow interferes with CGA.

eltair commented 5 years ago

Interesting. Even weirder, mine actually works fine with the onboard VGA enabled, and doesn't exhibit the cold boot problem.

jalgithub commented 2 years ago

I can confirm this problem. Booting the NuXT with an ATi Small Wonder rev 2 doesn't display anything, though the monitor is clearly driven (screen is black, as opposed to white when not driven). I have to wait about 10 seconds, then warm reboot for the CGA to work.

explit7 commented 3 months ago

This is exact the same issue, which i have on my Micro8088: https://github.com/skiselev/8088_bios/issues/73#issue-2383886346