Search found 8 matches

by Badwolf
Wed Jan 29, 2020 3:22 pm
Forum: HARDWARE ISSUES
Topic: New User with a Falcon problem.
Replies: 12
Views: 896

Re: New User with a Falcon problem.

I have a couple of Falcon's. One is a thing of beauty, one is turning into a bit of a pig. On boot the screen is completely white. RGB mode, VGA, etc., all the same. Apologies -- might be teaching granny to suck eggs -- but completely white display is what you see if the CPUBGI / CPUBGO jumper isn'...
by Badwolf
Wed Jan 29, 2020 2:05 pm
Forum: HARDWARE ISSUES
Topic: 68030 bootstrapping issue
Replies: 9
Views: 476

Re: 68030 bootstrapping issue

Hi guys, Quick follow up to let you know the state of play, since you've been so helpful: Holding /BGACK via the expansion header seems to have improved things -- or at least postponed the failure mode! The first couple of dozen bus cycles now act exactly as the onboard one does, but how long bus ac...
by Badwolf
Wed Jan 22, 2020 4:46 pm
Forum: HARDWARE ISSUES
Topic: 68030 bootstrapping issue
Replies: 9
Views: 476

Re: 68030 bootstrapping issue

The CT60/63 uses the bus grant signals as well as the halt signal. The reason for the use of the bus grant signals use is that when the DMA request the bus the "new" CPU has to release the bus and at that point this invalidate the halt state of the on board 68030, so the new CPU (actually the CPLD)...
by Badwolf
Tue Jan 21, 2020 2:26 pm
Forum: HARDWARE ISSUES
Topic: 68030 bootstrapping issue
Replies: 9
Views: 476

Re: 68030 bootstrapping issue

Could you disable 030 with RESET signal ? But as TF suggests, I think the "normal" method is to request the bus from the 030 and just never release it as the new 030 will take over as the main bus master. I assume thats how the CT60 does it. I think the reset on the expansion header (/XRESET) is ac...
by Badwolf
Tue Jan 21, 2020 2:17 pm
Forum: HARDWARE ISSUES
Topic: 68030 bootstrapping issue
Replies: 9
Views: 476

Re: 68030 bootstrapping issue

EDIT: Also verify /XHALT is correct and check the onboard CPU isnt getting hot. In my experience you need to hold 020/030's with BR/BGACK. Ah! That's an idea. /XHALT is held low (and measured low) when the card's enabled, but perhaps that doesn't do what I think it does. I'm a bit hazy on how the C...
by Badwolf
Tue Jan 21, 2020 1:54 pm
Forum: HARDWARE ISSUES
Topic: 68030 bootstrapping issue
Replies: 9
Views: 476

Re: 68030 bootstrapping issue

Thanks for the reply, guys. The arrangement is actually inspired by terriblefire 's early boards -- using a CPLD to gatekeeper the control lines through to the Falcon (buffer was the wrong word). The 16 data lines are basically wired directly to the upper 16 on the 030 and the address lines are wire...
by Badwolf
Mon Jan 20, 2020 5:31 pm
Forum: HARDWARE ISSUES
Topic: 68030 bootstrapping issue
Replies: 9
Views: 476

68030 bootstrapping issue

Hi guys, I'm quite a new member here, but am trying to build some hardware for my Falcon and hope you guys will be the best people to ask for tips. I'm making a little board for the Falcon -- plugging into the expansion headers -- which carries a PGA 030 chip. On the face of it, this doesn't do much...
by Badwolf
Tue Nov 19, 2019 12:18 pm
Forum: Terriblefire's channel
Topic: My Channel
Replies: 64
Views: 9491

Re: My Channel

Thanks for keeping the repos and the videos up, TF. I've been working through the vidoes learning as I go as I've been fancying building some hardware for my Falcon and Archie 3000 and very much liked your approach. I'd not really been aware of CPLDs before I saw your work and they seem like the mis...

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