Cost effective memory expansions for A1200

[vext01]

Hi,

I was wondering if there are any cost effective solutions for expanding the memory of an A1200.

My current setup is an A1200 with CF and a 1MB SRAM card. This is enough to run most of your OCS and ECS games with whdload, but not enough for pretty much any AGA game.

Most of the stuff I see on the market is in the form of an accelerator. I'm not too fussed about having a faster CPU. Are there any cheaper "memory only" expansions?

Thanks

[idrougge]

The ACA series was made because prices for old memory cards had risen so much.

[gulliver]

I still hope that someone builds an inexpensive (around 50 USD) simple 4MB ram expansion for the A1200 just piggybacking on the A1200´s 68020 cpu, or other motherboard chip that has the bus available.

It can even be a non autoconfig board to save costs, without any fancy stuff like RTC, FPU, etc. A simple DIY open project would be ideal.

The cost would be the small pcb, the socket to piggyback the 68020 (or whatever other chip we choose to get acces to the bus) and the 4MB of ram which can even be soldered static ram to avoid sockets, the extra refreshing circuitry, and any compatibility issues.

It would of course mean you will have to use the addmem command in the startup-sequence to have the fastmem available, but then it would be pretty cheap and double the A1200 performance whilst enabling nearly all whdload games to run.

[Daedalus]

Unfortunately, for the A1200 it's not as simple as that due to its design. The CPU can't be piggybacked, and piggybacking another chip is going to limit you regarding speed and address space. Budgie is probably the only chip that gives you relatively easy access to the bus, and that isn't piggyback-able either. Anyway,piggybacking chips like that will only give you a small advantage in that you don't need to source an A1200 trapdoor connector - other than that you're better off going for the trapdoor slot as it won't be any more complicated electrically. In fact, someone did prototype a simple RAM expansion card a while ago using (I think) a cut up PCI socket for the trapdoor connector. Such a beast might be the cheapest way of doing it yourself, but I can't find any reference to it now, and you'll still need some sort of minimal RAM controller on board.

[Predseda]

Originally Posted by Daedalus

In fact, someone did prototype a simple RAM expansion card a while ago using (I think) a cut up PCI socket for the trapdoor connector. Such a beast might be the cheapest way of doing it yourself, but I can't find any reference to it now, and you'll still need some sort of minimal RAM controller on board.

[Daedalus]

Yes, well there's that option too And if you already had one would simplify making a homebrew RAM card. But I was thinking of an actual RAM expansion card that someone built a while back. It may have been on Facebook that I saw it, I just can't find a reference to it anywhere at the moment.

[Bprepared]

Just a thought, but Plasmab's new CD32 card could be re-spun to an A1200 spec with little fuss, the trick will be obtaining the connectors though.

[idrougge]

I have a hard time seeing a home-made card with everything sourced in small quantities comparing favourably cost-wise against mass-produced 020 accelerator cards or even used RAM boards. I bought one for 20 € just a little while ago.

[vext01]

Which model did you get?

[Lord Aga]

Probably the Blizzard 060. It has a lot of RAM

[strim]

Originally Posted by gulliver

I still hope that someone builds an inexpensive (around 50 USD) simple 4MB ram expansion

But that was done before, in form of PCMCIA card. Well it was 50 EUR no USD, but still...
http://eab.abime.net/showthread.php?t=73095

All the files needed to build it are out there:
https://github.com/Sakura-IT/ppa-pcmcia-sram

Btw. in case anyone is crazy enough to build it on his/her own, use rev 2.1 files.