A500 4mb-8mb fast ram expansion

[waltermixxx]

Do you have any more 8 meg upgrades for A600?


Cheers

[dirkies]

I am still interested in an A500 model, but I did not get a reply on my email. Is this still for sale??

[Obliterator]

Wow lots of good stuff to get for my A500

[kipper2k]

New boards will be in my hands probably Friday/Monday

[kipper2k]

Hi all,

i am moving from Churchill to Thunder Bay soon so i will be in and out for the next 4 weeks while i have lots of things to sort at work and here in my apartment so be patient if it takes a while to get back to people. I'll still be building things but will be a little distracted.

If anyone doesn't mind the frigid North, my job will be going up for grabs


I have lots of new boards arriving Mon/Tues

[NovaCoder]

Love your work, good luck with the move

[Kai]

Hey - thread resurrection here, i know, but....

...will the likes of this board ever be seen in production again, even as bare PCB's?

[project23]

Originally Posted by Kai

Hey - thread resurrection here, i know, but....

...will the likes of this board ever be seen in production again, even as bare PCB's?

Obviously we'd all like one of kipper2k's cards, but since they seem unavailable I did stumble across this the other day...

https://github.com/kr239/A500-8MB-FastRAM

It's a little thru-hole heavy and i've not got any word on whether you can select for 4mb or 8mb (or indeed if it even works properly!), but I went ahead and ordered 5 PCB's anyway so I can have a play around.

Seems to be recently updated too?

John

[Kai]

...thats my github! I found the original project that it was based on and redid it in kicad as a through hole/easy to solder project for those of us with shaky hands.

You can select 4mb or 8mb if you want, but have to burn the right .jed's which i've not compiled with quartus yet - gimme some time

PCBWay have sent the first 10 PCB's to me, should arrive by Saturday.

[SukkoPera]

Well, it seems these expansions are pretty popular these days, as I also made my own versions, which are more similar to Kipper2k's. I made both A500 and A600 versions.

Check out the other thread if you are interested:

http://eab.abime.net/showthread.php?t=97459

@Kai:I think we met on Twitter

[project23]

Originally Posted by Kai

...thats my github! I found the original project that it was based on and redid it in kicad as a through hole/easy to solder project for those of us with shaky hands.

You can select 4mb or 8mb if you want, but have to burn the right .jed's which i've not compiled with quartus yet - gimme some time

PCBWay have sent the first 10 PCB's to me, should arrive by Saturday.

Hah! Small world! I've also got five boards arriving at the weekend, so consider me a beta tester lol

John

[8 Bit Dreams]

Originally Posted by project23

Hah! Small world! I've also got five boards arriving at the weekend, so consider me a beta tester lol

John

Watch out, these will probably not work on A2000, because the autoconfig chain is broken.
You would have to split the AS signal and hide it for RAM autoconfig cycle.
In other words Amiga must not be aware of the autoconfig cycle of the FastRAM, because otherwise the first Zorro slot card would register.
Same for A500 - will be a problem as soon as something hangs on the expansion port.
CDTV will not work either, because there is ALWAYS a DMAC autoconfig, A2000 exits as soon as an expansion card is in it.. We already gone thru it some time ago. We tried to make them work together with TF530 cards back in the days and this was the issue.

[SukkoPera]

If that board is based on lvd's design like mine, it can be flashed with the non-autoconfig firmware. This should solve all of those issues, but then the RAM will need to be configured manually with addmem.

[project23]

Originally Posted by 8 Bit Dreams

Watch out, these will probably not work on A2000, because the autoconfig chain is broken.
You would have to split the AS signal and hide it for RAM autoconfig cycle.
In other words Amiga must not be aware of the autoconfig cycle of the FastRAM, because otherwise the first Zorro slot card would register.
Same for A500 - will be a problem as soon as something hangs on the expansion port.
CDTV will not work either, because there is ALWAYS a DMAC autoconfig, A2000 exits as soon as an expansion card is in it.. We already gone thru it some time ago. We tried to make them work together with TF530 cards back in the days and this was the issue.

Thanks for this. I imagined that getting it to work with my setup would require a bit of playing around with the verilog.

Can you just confirm for me whether or not that would be sufficient? I.e can this be sorted in the firmware, or is it an issue with the board itself.

I have five boards and was going to build one up, but I won't bother if there are board-bound issues.

I don't mind playing with the verilog - that's partly why I wanted to build it. I'd like to get 4mb working with my TF530 and I know I need it to autoconf into 60000+ rather than 20000, so knew there would be some fiddling involved.

Worst case - I don't mind using addmem on boot with no autoconf, but the verilog part was kinda the point of me playing.

Cheers dude,

John

[SukkoPera]

I don't get it though. The TF530 is said to be compatible with Kipper2k's 4 MB expansion, which is a 1:1 implementation of lvd's design. So did he modify the verilog?

[project23]

I believe Stephen may have played with it at one point... Not entirely sure if changes were made.

All I know is that for obvious reasons it can't claim 0x0020000...

If it works with addmem surely it can just be tweaked anyway?

[SukkoPera]

Yes. I'm not fluent in verilog but looking at the code it seems it doesn't pay attention to the address autoconfig actually assigns it and just assumes it will be $200000. It should only be necessary to actually store the assigned address and use it when decoding addresses for memory selection.

Although in verilog this might not be as easy as it sounds .

This is just to make it play nice with the TF530. The autoconfig issue reported by Viktor above is a different issue.

[project23]

Right, yeah, so i'd have to have the card play naughty still, but have it grab 0600000, or fix it completely and have it use the address autoconfig assigns it?

I mean, this is fine. I do look forward to learning a bit of verilog by playing around like this.

And as a 'failsafe' if i can just use it with addmem then that'll let me sanity-check my soldering etc.

Cool,

John

[SukkoPera]

I think it should work fine with addmem if you use the non-autoconfig firmware. Still need to test that with my boards though.

If you do the fix, of course it would be great if you did a full and nice one . I'll also look into it when I have time.

[project23]

Yeah i mean don't hold your breath, haha. I'm completely new to verilog itself, but the hardware has become such an interesting hobby for me that it is something I am looking forward to playing with.

I figured that a simple memory card for the Amiga would be a relatively simple place to start, ya know?

I'll probably give your card a build too. Kai's pcb's have just arrived, i'm gunna put an order in for some more stuff soon and i'll probably do a couple of your PCB's too.

John