Amiga 500 rev5 - Kickstart 3.1 upgrade issues

[dirkies]

standard OCS Agnus in my A500 rev5 (8371)
But ordered an ECS 1MB 8372A one so I can mod the trapdoor RAM into chip RAM.

[Zippy Zapp]

Originally Posted by dirkies

standard OCS Agnus in my A500 rev5 (8371)
But ordered an ECS 1MB 8372A one so I can mod the trapdoor RAM into chip RAM.

Props to Kipper for figuring out the mystery. That will be helpful when I upgrade the 500 Rev 5 I have which has an 8371 Agnus.

Where do you find the 8372A chips? I need one for an A2000, NTSC. I think the 8372A is PAL and NTSC, iirc.

[dirkies]

got mine from Vesalia. They have almost all OCS/ECS chips in stock except super denise.

[Zippy Zapp]

Originally Posted by dirkies

got mine from Vesalia. They have almost all OCS/ECS chips in stock except super denise.

Awesome. I have ordered from them in the past (A500 Keyboard Membrane).

Thanks for the info!

[Psygore]

I bought the rom 3.1 from AmigaKit too some months ago and have the rom checksum error (red screen) when booting on:
- A500 rev 5 with a Fat Agnus 8372A (modified socket rom)
- A500+ rev 8, Fat Agnus 8375 (not modified socket rom)

I connected an ACA500 (booting with the soft-kicked 3.1) to dump the physical ROM and found 1 different bit.

Of course, the rom 3.1 was checked and re-checked by AmigaKit on several amiga and they didn't find something wrong.

[cpiac64]

tomorrow test 3.1 on my rev 5 with 8371 and rev 5 with 8372a

[cpiac64]

tested, 3.1 wire mod work fine on rev5 green pcb with 8371 or 8372a and with or without 512k trapdoor

[dirkies]

well, seems it may not be the exact same eprom used for your 3.1 rom, or there are other differences in components on the mobo causing this (as C= was famous for sourcing components from different manufacturers for the same models)

[kipper2k]

The plot thickens

[cpiac64]

kick 3.1 with wire mod work in a500 rev3

[danko]

I have a Amiga 500 motherboard REV 5 and REV 6A work Kickstart v2.04 rev 37.175?

[cpiac64]

in the rev5 need modifiy
in the rev6 work fine

[dirkies]

My rev 5 required a patched eprom 3.1 even with wire mod to make it work (none of commercially sold ones worked). For 2.x I don't think there is an issue, mine worked fine with just the wire mod (was not an eprom may I add)

[DesktopDynamite]

I have successfully installed KS3.1 ROM on a Rev5 brown mobo using the wire mod. Also installed kipper2k A508 fastmem board. Boots classicwb 68k successfully from an 8gb cf card . Now I bought the 8372A chip from
http://www.amibay.com/showthread.php?t=82012 to load more games which require 1MB chipmem. Thus the 8372A tricks the trapdoor RAM expansion slow mem into being chipmem...

Sent from my GT-I9301I using Tapatalk

[crashserious]

First post, created an account just to add this here since google sends people here after a search of this issue pretty high up in the returned sites list. Hopefully it helps!



So I realize this is an older thread, but I just encountered this issue as well. And as an experienced IT Professional, who also has a background in electronics, I just about scared the heck out of myself thinking I'd fried my beloved Rev5 Amiga 500 to simply add a HDD side car.


The text on that page SHOULD read:


On the ORIGINAL socket on the A500 motherboard, connect pins 1 and 31 of the socket. Then pull pin 31 on the CHIP out so that it does not go into the socket.



Plug in the chip into the socket (or riser socket) and jumper pin 21 to teh pulled out pin 31 on the CHIP.


That works!


DO NOT Jumper all three together, that doesn't. It doesn't seem to fry anything-- but I suppose it could have.

if you are coming from 1.2/1/3 know that it takes longer at a black screen to boot from a floppy if no HDD is present, I read about 30 seconds... and that seems right.

Originally Posted by Viserion

I used A500 rev5 Kick3.1 Upgrade

Get a socket to do the soldering on. It's easier, and is easier to reverse should you want to in the future.

As you can see in the link I provided you should bend pin 31 up so it has no contact with the socket.

Then solder the pins.


I needed the 3.1 rom for an another Amiga, so I removed the 3.1 rom and inserted a 1.3 rom instead(mine had originally a 1.2 rom).

I still have the socket I modified so I could change again.

Tried to find it so I could take a better/bigger picture for you, but don't remember where I put it.

Anyway, I succeeded using the link above

[LSone]

I'm trying to install a rom switcher 1.3/3.1 into a rev 5 A500. I believe that I need to do this mod, anyone have an updated link to the instructions? I intend to use an extra socket I had laying around instead of directly modifying the mainboard.


Thanks!

Originally Posted by Viserion

I used A500 rev5 Kick3.1 Upgrade

Get a socket to do the soldering on. It's easier, and is easier to reverse should you want to in the future.

As you can see in the link I provided you should bend pin 31 up so it has no contact with the socket.

Then solder the pins.


I needed the 3.1 rom for an another Amiga, so I removed the 3.1 rom and inserted a 1.3 rom instead(mine had originally a 1.2 rom).

I still have the socket I modified so I could change again.

Tried to find it so I could take a better/bigger picture for you, but don't remember where I put it.

Anyway, I succeeded using the link above

[theq]

I believe this might be useful http://eab.abime.net/showthread.php?t=82824.
It gives you an insight of the problem and a solution to fix the problem with the rev.5 motherboards.

Hope it helps

[cypher007]

Originally Posted by dirkies

My rev 5 required a patched eprom 3.1 even with wire mod to make it work (none of commercially sold ones worked). For 2.x I don't think there is an issue, mine worked fine with just the wire mod (was not an eprom may I add)

hello,

im having a similar issue. mine will boot but i get a yellow screen briefly on warm boot.

what needed to be patched?