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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Tahoe on December 12, 2004, 10:36:23 AM

Title: A500 rev8 upgrade?
Post by: Tahoe on December 12, 2004, 10:36:23 AM
I have received an A500 with a revision 8 mainboard. As far as I know the rev8 is the board used in an A500+. This however is a regular A500.
What do I need to do to make it a +? The Agnus is the 8375, the Denise however is the older one (8362R8?).
Onboard half the memory sockets are populated, if I just solder in the other half will it work or do I need some extra parts?
Title: Re: A500 rev8 upgrade?
Post by: poweramiga2002 on December 12, 2004, 10:53:03 AM
gday i have an A500+ rev8.1a it has a full 2meg chip and 2 meg fast

so if you put all chips on main board you should get 2 meg chip ram and then the trap door will just give you fast ram

ive only ever seen 1 rev 8.1a and i have it
let me know how you get on with it
Title: Re: A500 rev8 upgrade?
Post by: Tahoe on December 12, 2004, 12:33:07 PM
This one has only 512K of Chip. Found another little problem with this bugger, the mouse. It goes up and down but not left to right. It's a little like playing Quake, you need both keyboard and mouse to move around :(
Swapped the CIA's, that didn't help.... Help? Maybe one of the capacitors or thingy's next to the port?

BTW; I wonder if the 1MB expansion (trapdoor) i bought for this machine (it is suitable for an A500+) will work with this baby. Also, will I get 1.5mb of Chipram?
Is it for this rev 8 also the case that if I fit an extra 512K on the Mainboard the trapdoor becomes useless?
Title: Re: A500 rev8 upgrade?
Post by: tomekm on December 13, 2004, 09:25:12 AM
Title: Re: A500 rev8 upgrade?
Post by: Michael_D on December 24, 2004, 01:29:08 AM
Hi,

read http://www.fh-luh.de/~spider/Amiga/Hacks/A500.txt . :-o
(only German but may be helpful :-D )
Title: Re: A500 rev8 upgrade?
Post by: Michael_D on December 24, 2004, 01:29:28 AM
Hi,

read http://www.fh-luh.de/~spider/Amiga/Hacks/A500.txt . :-o
(only German but may be helpful :-D )
Title: Re: A500 rev8 upgrade?
Post by: SHADES on December 24, 2004, 03:05:07 AM
Rev 8 is a standard AMIGA 500
Rev 8.10a is the AMIGA 500+ that has the ability to do some extedned graphics reolutions due to an updated Denise chip and not much else. The trapdoor fast ram is not true fastram, but slow chipram re-mapped to the fastram address. It was nicknamed SlowFast ram.
p.s. I also have one :)
What I don't have is a AMIGA 1500 or was it the 2500 :( I forget now. :(
Title: Re: A500 rev8 upgrade?
Post by: Tahoe on December 24, 2004, 08:05:15 AM
Both exist, a 1500 is either a custom built A500 (was basically a casing made by Checkmate in the UK) or a rebadged A2000 with two disk drives and a black Amiga logo on the front.
The 2500 is basically a 2000 with accelerator (020 or 030) and a SCSI controller.

But back to my A500. I am not quite sure whether it's a 8 or an 8.1. Stuffed a 1MB expansion in the trapdoor slot but it sees it as only 512K. Strange machine this is.... The Agnus is the 8375 so should be the 2MB version.
Title: Re: A500 rev8 upgrade?
Post by: Tahoe on December 24, 2004, 08:07:55 AM
Quote

Michael_D wrote:
Hi,

read http://www.fh-luh.de/~spider/Amiga/Hacks/A500.txt . :-o
(only German but may be helpful :-D )


Fantastic! Thanx! That was just what I was looking for!!