User avatar
Hook
Ottawa, Canada

Posted Mon Mar 14, 2022 6:33 pm

Got the board installed in the A1000 per the instructions and when I turn it on, the power LED flashes, screen cycles from black to grey to green.

If memory serves me right (sorry for the bad pun), green is the color code for faulty ram, correct?

I currently have KM44C256CP-6 chips, can I use other types? I found a seller on eBay that has 70ns chips, would they work too or do I absolutely need 60ns?
20220314_211634.jpg

User avatar
Hook
Ottawa, Canada

Posted Tue Mar 22, 2022 8:47 am

Update:

Got a DRAM tester today and promptly proceeded to testing the chips. The result is 6 good chips, one bad and one fake (labelled as 256k but actually 16k)

So now to the next step. Can I mix various DRAM speeds like on modern PC SIMM/DIMMs where the system will slow down to the lowest memory speed installed? Because finding the EXACT same chip I have is proving to be a challenge.

I have 256kx4 @ 60ns, but the closest match I've found at a reasonable price are 256Kx4 @ 70ns. Do I need to replace all 8 or can I swap the two faulty 60ns ones with working 70ns?
275430961_7213452088728419_3496893439784951394_n.jpg

User avatar
Hook
Ottawa, Canada

Posted Tue Mar 29, 2022 5:32 pm

Update #2:

Continuing my monologue with this third post -

Received new DRAM chips today and proceeded to testing them. They all passed, woohoo! I proceeded to fitting the Rejuvenator board in the A1000 and presto! It works!
20220329_191021.jpg
However, it would not be a true Amiga experience if I did not have issues. I swapped the 68000 for a Pistorm, one that was confirmed working with the A1000's stock daughterboard, and it does not work with the Rejuv. Nada.

Put back the 68000, the Rejuv works, but not the Pistorm.
Put back the the stock daughterboard and the PiStorm works. Huh.

User avatar
EzdineG
Springfield, MO

Posted Tue Mar 29, 2022 6:59 pm

Hook wrote:
Tue Mar 29, 2022 5:32 pm
Put back the 68000, the Rejuv works, but not the Pistorm.
Put back the the stock daughterboard and the PiStorm works. Huh.
I have no issues using the Pistorm with a Rejuvenator. I tested with the Emu68 version and a Pi Zero 2W.

Is anything else changing when you swap them? ie. socket extender / relocator that otherwise wouldn't fit? You might inspect the 68000 socket pins to make sure they aren't starting to fail. Does it change anything if you remove the Denise RGB2HDMI adapter?

Are you sure all three of the connections from the Rejuvenator are correctly made to the motherboard? You might also solder a lead to the ground if you aren't already doing so - my 1000 didn't need it.

User avatar
obitus1990
USA

Posted Tue Mar 29, 2022 7:12 pm

where did you get the RAM tester?

User avatar
Hook
Ottawa, Canada

Posted Wed Mar 30, 2022 5:42 am

obitus1990 wrote:
Tue Mar 29, 2022 7:12 pm
where did you get the RAM tester?
From this eBay seller: https://www.ebay.ca/itm/124803897060
EzdineG wrote:
Tue Mar 29, 2022 6:59 pm
I have no issues using the Pistorm with a Rejuvenator. I tested with the Emu68 version and a Pi Zero 2W.

Is anything else changing when you swap them? ie. socket extender / relocator that otherwise wouldn't fit? You might inspect the 68000 socket pins to make sure they aren't starting to fail. Does it change anything if you remove the Denise RGB2HDMI adapter?

Are you sure all three of the connections from the Rejuvenator are correctly made to the motherboard? You might also solder a lead to the ground if you aren't already doing so - my 1000 didn't need it.
No extenders, no relocators. I am also using a Pi Zero 2W and snipped the corner of the board to get clearance from the floppy drive casing. The Rejuvenator is firmly installed and there are no gaps between it and the Denise/Agnus/Paula sockets.

My 68000 socket seems to have a lot of mileage on it though. I pondered replacing it but my Google-fu has proven unfruitful. Might just solder a couple of pin strips in lieu of an actual socket.

And what's this about a ground lead? There's a ground connector on the Rejuvenator, are you suggesting I should connect a lead and solder it to the ground plane on the A1000 mobo?

It's frustrating. Every time I take two steps forward, I take one step back. It's the Amiga way I suppose :lol:

User avatar
EzdineG
Springfield, MO

Posted Wed Mar 30, 2022 6:48 am

Hook wrote:
Wed Mar 30, 2022 5:42 am
My 68000 socket seems to have a lot of mileage on it though. I pondered replacing it but my Google-fu has proven unfruitful. Might just solder a couple of pin strips in lieu of an actual socket.

And what's this about a ground lead? There's a ground connector on the Rejuvenator, are you suggesting I should connect a lead and solder it to the ground plane on the A1000 mobo?
I have previously replaced my 68000 socket; plug a machined pin header into it a handful of times and consider it a requirement.

The A1000 is known to have problems with daughter board grounding. Since you're seeing some odd behavior, it probably wouldn't hurt to ground the Rejuvenator to the motherboard.

User avatar
Hook
Ottawa, Canada

Posted Wed Mar 30, 2022 7:25 am

EzdineG wrote:
Wed Mar 30, 2022 6:48 am
I have previously replaced my 68000 socket; plug a machined pin header into it a handful of times and consider it a requirement.

The A1000 is known to have problems with daughter board grounding. Since you're seeing some odd behavior, it probably wouldn't hurt to ground the Rejuvenator to the motherboard.
Thanks for the tips, I will try the above suggestions and report back.

User avatar
Hook
Ottawa, Canada

Posted Mon Apr 04, 2022 8:08 am

EzdineG wrote:
Wed Mar 30, 2022 6:48 am
The A1000 is known to have problems with daughter board grounding. Since you're seeing some odd behavior, it probably wouldn't hurt to ground the Rejuvenator to the motherboard.
Right.

I've grounded the board from the GND pin on the Rejuvenator to the big shield on the floppy drive and have replaced the CPU socket with round machine pins.

The issue is still there but then I noticed intermittent crashes and sometimes a green screen on boot, which is RAM or custom chips. Pressed on the Agnus chip, got visual artefacts on the screen. Sometimes the system will work for several minutes, then lock up. If I reinstall the original daughterboard, it's smooth sailing.

So the next step is figuring out if I have a faulty 8372A chip or a faulty Agnus socket.

More to come!

User avatar
EzdineG
Springfield, MO

Posted Mon Apr 04, 2022 9:56 am

Maybe dirty contacts on the Agnus ? Otherwise, I'd swap the socket.





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