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skiselev / micro_8088

Micro 8088 - IBM XT Compatible Processor Board based on Faraday FE2010 chipset
GNU General Public License v3.0
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CGA Cards works only after reset or second PowerOn in Micro8088 #21

Closed explit7 closed 2 months ago

explit7 commented 2 months ago

Hello @skiselev and other collegues! I have a strange issue with CGA Cards on Micro8088. Doesnt Matter ift it is a Cycle Logic CGA or Graphics Gremlin Card, it works only after second PowerOn cycle or reset.

If i switch Micro8088 for the first time - i have garbage on the screen (Cycle Logic CGA Card) or constant Graphics Gremlin Test Pattern (Graphics Gremlin 1) which stays static. The computer boots in the background, but the screen stays static.

GG_Pattern

Thats very strange, in another XT Mainboard (TripleD TD-20) both cards works without any issues. VGA Card works also without any problems in Micro8088.

The CGA Card occupies the next ISA Slot after Micro8088 Board, in another Slots it the same issue. Could it be timing issue, that the CGA Card need more time to initialize?

I have following cards in My Micro8088 System:

Any ideas, where this problem is coming from?

Update: Here seems to be the same issue: https://www.andavno.com/?p=248

explit7 commented 2 months ago

Close, as opened in the wrong Repo. It belongs to the 8088_bios Repo.