User avatar
mtp66

Posted Sun May 01, 2022 4:10 pm

I had a Hitachi Processor (HD68000P8) and I replaced it with a Motorola (MC68000P8) and that fixed the issue. No more black screen with J100 closed.

Keep in mind that it does take around 10 seconds or so for it to request the Kickstart disk.

User avatar
EzdineG
Springfield, MO

Posted Sun May 01, 2022 4:36 pm

Dragonheart wrote:
Sun May 01, 2022 2:23 pm
The issue with J100 is solved:

If you have an Hitachi (HD)68000, J100 will not work and cause a black screen when set.

If you use a Motorola 68000, J100 will work as expected. It doesn’t matter if the CPU is plastic or ceramic, but it has to be an original Moto. Guaranteed.
Interesting. We saw some similar shenanigans with that Atari ST's DMA and certain hard drive adapters. CMOS 68000's would work fine, but original HMOS would load the bus with errors.

It may just be there will be certain combinations of motherboard / processors that will produce different results.. especially with regard to third party addons.

Great find!

User avatar
Dragonheart

Posted Mon May 02, 2022 8:38 am

jdryyz wrote:
Sun May 01, 2022 2:39 pm
I have a Motorola 68000 and still have the black screen.
Try a P8 instead of the G8 (if you have one)

User avatar
jdryyz

Posted Mon May 02, 2022 9:02 am

I thought I did have another one stashed away (pulled from my A2000) but I cannot locate it. It is probably with my A2k cpu slot adapter which I have also misplaced.
Last edited by jdryyz on Wed May 11, 2022 7:06 pm, edited 1 time in total.

User avatar
jdryyz

Posted Wed May 11, 2022 7:05 pm

I received a 68000P8 today.

JP100 now works!!

So, I gotta ask- what is it about these differences in the 68000 that would make the Rejuvenator not function correctly? I confess, I did not even know someone other than Motorola made a version but I also did not know that there were different clock speeds in the 64pin package.

I can certainly understand how the Rejuvenator may not like a faster 68000 instead of the stock 8Mhz, but I didn't try to use a faster one. I cannot find any info on the G vs P variants. Perhaps some subtle timing differences?

Certainly these variants existed back in the day so wouldn't there be documented cases about people experiencing black screens with original Rejuvenator boards? I admit I did not *thoroughly* read the original instructions. I mostly focused on the installation portion.

User avatar
McTrinsic

Posted Thu May 12, 2022 3:01 am

The Phoenix Board from back then knows of a similar issue. The manual at Amiga.resource.xx.

On page 11 of the manual, you get this text:

„If your CPU is manufactured by Thomson (…) or Hitachi, the problems of overloading the bus may occur. As the Phoenix Boards‘s SCSI controller and Expansion slot are in effect loading the bus, it is likely that problems will occur. We strongly advise all people to change to a ‚Motorola‘ type to avoid problems.“

So yes, things like these were known back then.

Cheers,
McT

User avatar
olDirdey

Posted Wed Jun 29, 2022 3:11 am

edit: seems no one cares about it

User avatar
obitus1990
USA

Posted Sun Jul 17, 2022 7:00 am

olDirdey wrote:
Wed Jun 29, 2022 3:11 am
edit: seems no one cares about it
What was it? I hate seeing content lost. :(

User avatar
Appee

Posted Fri Dec 23, 2022 5:51 pm

McTrinsic wrote:
Thu May 12, 2022 3:01 am
The Phoenix Board from back then knows of a similar issue. The manual at Amiga.resource.xx.

On page 11 of the manual, you get this text:

„If your CPU is manufactured by Thomson (…) or Hitachi, the problems of overloading the bus may occur. As the Phoenix Boards‘s SCSI controller and Expansion slot are in effect loading the bus, it is likely that problems will occur. We strongly advise all people to change to a ‚Motorola‘ type to avoid problems.“

So yes, things like these were known back then.

Cheers,
McT
You mentioned your adspeed didn't work with the parceiro 2. Any chance it's the 68k's fault?

User avatar
intric8
Seattle, WA, USA

Posted Fri Dec 23, 2022 5:56 pm

You mentioned your adspeed didn't work with the parceiro 2. Any chance it's the 68k's fault?
David and I had a similar thought. I changed the CPU out with a spare I had sitting in an A2000 motherboard chip graveyard and had the same results. David and I are looking at a possible solution; I should know in the next couple of weeks (fingers crossed). In the meantime I started looking around for a 68010. I could have sworn I had one, but I can't find it anywhere. I can't remember if I put it in my Phoenix or what the heck I did with it. I wish there was a source online where they could be easily found or I'd pick one up just to have for a backup.

The annoying part is in my tray-box where I keep all my spare loose chips, in the CPU tray there is a sticker that fell off that says "010". And yet there is no chip to match! So I know I must have one - or had one. I'm a lamer.





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