liv2 / a500-2meg-chip-ram Goto Github PK

Hi Team,
I have made up a few boards using the PLCC method. I now get a black screen and diagrom fails to start.
I am using Diagrom VIA a Pistorm which normally gives me serial output on screen but it just hangs.
I am using a Rev5 board which has pin one of the Agnus pointing down.
Only thing I have different on my boards is that I have not install the 74AHCT158 multiplexer and just connected 28M jumper.
Could this have something to do with it? I have now ordered some HCT158 chips and hope this may sort out the issue.
Any thoughts are welcome.
Thanks

Any idea where to connect A20 when using on a Rejuvenator Board in an Amiga 1000, other than CPU Pin 48, to use 2MB ChipMem? Works fine without A20 connected and 1MB ChipMem or with A20 connected with CPU Pin 48 and 2MB ChipMem.

Thx in advance

Can someone confirm this for me? I'm reading that a PAL 318069-xx AGNUS can work on an NTSC Amiga?

https://eab.abime.net/showthread.php?t=92402

I'd love to be able to upgrade my NTSC A2000 with this board.

I installed this board into an A2000 Rev 6.2 and now I only see a black screen, even with DiagRom. I am using this with a 390544-01 in PAL mode. Any assistance would be appreciated. A20 is connected to pin48 on the CPU.

Hi Team,
Could be a silly question. All screenshots I see the 2meg adapter mounted horizontally.
With my motherboard, pin 1 face down and not to the right of the socket.. So would that mean I mount the adapter vertically?
Just want to make sure as pictures from https://bigbookofamigahardware.com/bboah/media/download_photos/a500mb_rev5_3.jpg
show that pin one is down but the agnus in this screenshot is facing to the right. My Amiga has the Angus mounted with pin 1 down.
Hope this makes sense.

I have an 318069-19 which is a late-model NTSC Agnus from an Amiga 3000. It is my understanding that these have a different pinout from the Agnus chips from the A600/A500+ and are replacements for the old 8372B and 8372AB.

I just get a black screen, so it does not work...

Is there a list of known working Agnus revisions?

Would it be possible to have a version of this board that works in A500+ (in fact A500++) motherboard?

This would be extremely useful when repairing an A500 Plus with the Rob Taylor's A500++ board.
I found your "Diet-Agnus-A500-plus" via his Tindie DIY projects page, but it is "only" 1MB and I have of course the 8375 Agnus.

I would like to keep my A500 Plus motherboard untouched and having RAM in a board like this seems very nice indeed.

I love soldering stuff, but I can't design these thing and I don't think I have the years left anymore to learn :)

Hello everyone. I have tried to grab parts for a small batch of these and found that 74AHCT158 is near impossible to get my hands on.
Seems to be out of stock. Is there are substitute for this chip that can be used?

Thanks