Poll, new accelerator for A500/A600.

[alexh]

It would be too expensive to make one that will fit both A500 and A600 since the A600 has a square PLCC surface mount 68000 and the A500 has the Rectangular socketed DIL 68000.

Keep it to A500/CDTV/A2000 if I were you.

Unless you are a PCB designer I very much doubt that you'll ever get this done. The NRE for such a project will be 2 or 3x the amount of money you'll ever make.

K.I.S.S. "Keep it simple stupid". Go with an ultra simple CPU + RAM only design to start with.

[alexh]

@hppacito

If you can not do it, doesn't mean that no one else can not do it.

I am not saying I couldnt do it, or that you couldnt do it. I am an ASIC engineer, I've worked on multi-layer Set-top-box PCB's in the past. I have access to Protel, Orcad etc. I am sure that I could do it, but I have no real incentive to do it.

In my opinion, and it's just that, it's too complicated for a first time project. What you are planning will take a long time, require a great investment of time and money and in the long run there is no real chance of any recompensation, and lots of chance it will require an expensive re-spins.

I would say all of this if it was a 680x0 board, but a coldfire board makes it 2x as risky again.

The FAST RAM expansion for A600's on the otherhand is a very feasible idea. The PCB will be relatively simple, the cost to produce will be very low, you stand a greater chance of enjoying such a project, finishing, and even though there are not that many A600's out there you stand a good chance of selling a few.

[alexh]

If you are determined to do it, even if it ends up just your own Prototype, talk to Oliver Hannaford-Day, creator of the great CDTV webpage and the last coldfire project.

http://www.cdtv.org.uk/coldfire/1154.html

He was trying to do a coldfire A3000/A4000 accelerator, but software and other things prevented it's release.

http://groups.yahoo.com/group/amigacoldfire/

He'll be able to help no-end with ideas and how to overcome board related problems.

If you could find a relatively cheap source of E41J 68060 CPU's (the ones that can clock at upto 100MHz) then I would recommend a design with one of those instead of a coldfire. You eliminate the headache of software compatibility.

Also speak to Rodolphe of czuba-tech. He recently did an 060 based design for the Atari Falcon and used an FPGA/CPLD to create an SDRAM controller.

http://www.czuba-tech.com/CT60/english/overview63.htm

[alexh]

The advantage of having only 4M is that the PCMCIA is still usable.

Edit:

Yeah unfortunately the standard A600's address range is limited to 24-bits (16Mbytes)

$000000-$07FFFF    Chip RAM
$080000-$1FFFFF    Reserved
$200000-$5FFFFF    Fast-RAM (4Mbyte)
$600000-$9FFFFF         PCMCIA   (4Mbyte)
$A00000-$BEFFFF    Reserved
$BFD000-$BFDF00    PIA B (even addresses)
$BFE001-$BFEF00    PIA C (odd addresses)
$C00000-$DFEFFF    Reserved for expansion
$DFF000-$DFFFFF    Custom chip registers
$E00000-$E7FFFF    Reserved
$E80000-$EFFFFF    Expansion ports
$F00000-$F7FFFF    Reserved
$F80000-$FFFFFF    System ROM

4Mbytes of FAST RAM (6Mbytes in total) is more than enough for a good WHDLoad system.

[alexh]

@leirbag28

Hmmm Im not sure what everyone her is talking about saying the A600 is limited to 4Mb....thats NOT true.

Yes it is, if you only have a stock 68000.

I had an Apollo 630 with 32mb ram and PCMCIA Ram card.they both worked simultaneously

But you added a processor with 32-bit address lines instead of a 24-bit!

As long as you dont use anything below a 68020 (excluding EC020 cos they are still 24-bit) you can have more RAM.

if your just gonna make a board that adds 4MB, that is a waste as there are plenty of 4Mb PCMCIA cards availble..people here just dont know where to look for them

For people who have a PCMCIA hard drive / flash drive it's not a waste. If you are going to add a CPU above EC020 then 4mb isnt a limit.

Please dont settle for a measly 4mb. We need 128Mb in that thing minimum. and at least a 68030 @50mhz, and also dont put RAM on it.....make a slot for up to 1GB of ram, or at least 256........

You power hungry maniac! A spec like that would make it difficult and expensive.

Jens Shoenfeld, he is palnning on creating the Apollo 630 line again

Jens Schoenfeld is thinking of making a NEW 68030 accelerator for the A600, NOT the Apollo a630 cos their design is too unstable.

he also gave us the A600 clockport for USB upgrades.......I am a proud owner of one

He sure did, but without a CPU upgrade, it's useless

[alexh]

PLCC socket: empty, can be populated with a 68881/2

Why have an FPU? Nothing of any significance in the Retro Amiga world (aka Games / WHDload / OS) uses it. The PLCC socket is expensive, difficult to solder, easily broken.

You could have used an non EC 68020 and added more RAM (that doesnt interfere with PCMCIA) for the same price!

I think you should also choose to do one or the other A500 Accelerator OR A600 accelerator, rather than try to make a universal design. A500 offers probably greater return as there were/are more of them and the GVP A530 on ebay always brings big prices.

[alexh]

Nobody is talking about a Stock A600

I was. A 4Mbyte A600 FAST RAM upgrade, nothing else, low cost, 20-30 Euro's. I'd be up for one more than a 200 euro accelerator!

Jens looked at simply cloning the Apollo A630 design, however when measuring the signals on an oscilloscope going between the motherboard and the FPU he determined it was pure luck that they work at all.

I do not think the new design has an FPU.

[alexh]

Those cards dont work as RAM in A600/A1200's

[alexh]

@doppie1200

We've had this conversation. The A600 uses a different shaped CPU which is soldered to the motherboard. It is unlikely (but not impossible) that you could create a single design to work with both machines.

[alexh]

Flash cards dont have removable batteries, just SRAM cards.

These are not SRAM cards and dont work as RAM in the A600/A1200.

With the flash driver available on Aminet you could probably used them as a fixed disk... but for 8 mbyte!

[alexh]

@jethro_Tull the project you refer to was being done by Jens Schoenfeld of http://www.ami.ga and originally it was going to be a remake of the A630 however it became clear to Jens that they are rubbish, easily break, dont work very well. So he began to make a new 030 based accelerator. Work has been done but not finished.