Introducing ACA 1221 Low Cost Accelerator At AmigaKit.com

[Schoenfeld]

WHDload has quite a few options to make things work, where the easiest of them is to play with caches. The ACA1221 has a 68020 processor, which has only iCache, so all options are easy and quick to work through. When we're done testing the new ACA500 firmware, you can also play with CPU speeds.

On the ACA500, people sometimes forget that they don't have an AGA machine. AGA games cannot be played on OCS/ECS :-)

Jens

[CrashMidnick]

No workaround found for the games I listed. Tried nocache, cache, novbrmove, noautovec... None of them worked.
Well as said before, every single accelerator has its incompatibilities with whdload games. If I really want to play the games and demos (like world of commodore 92) that do not work with an accelerator, I remove it and the ACA500 plays them just fine.

Well this is not related to ACA1221 but ACA500, sorry for the OT Jens I will stop there.

[Dejavu]

Jens,
My setup is consisting from an Amiga 500+, ACA500, ACA1233, Indivision ECS, Rapidroad USB. Although using an ATX-PSU which is 350Watt of good quality, artifacts always occur when CF is reading. Please see this short video : [ Show youtube player ]

If i use ACA500 alone, that black line issue is almost* not seen anymore. (*even so sometimes i saw them.)

Meanwhile video output from Amiga' RGB port is flawless even if with all components connected together. Problem solely comes from VGA output of Indivision ECS.

So i think ( i don't know how to express) the required power for whole system should be decreased.

At this point, for power consumption, do the ACA1221 have noticeable improvement over ACA12XX ? (especially ACA1233).

Do you think, using this card solves my problem? What is your other recommendation?

[Schoenfeld]

Your problem is power-supply related. You are using an ATX power supply, which by itself is a huge no-go, as they normally don't have the 5V rail as their main power rail. This means you have high ripple on the 5V line, along with poor regulation, because the main 12V power rail is under-loaded.

We did solve quite a few problems with A500+Indi-ECS power issues with a patch on Indivision ECS. Please contact your reseller to find out if your unit is already patched (been delivering them with the patch for a good two years now), or if it may still need that patch.

Jens

[Retrofan]

Originally Posted by Schoenfeld

Your problem is power-supply related.
Jens

Another and another and another and more each day... Please help us

[Dejavu]

I found an old A500 PSU. I measured lines to verify it is alive.... And it worked, no artifacts, no flickering , no black line, just perfect.

It is heavy but provides only 2,5A@12V.

Anyway lesson learned: the new isn't always the best, give a chance to the oldies

[daxb]

The problem is that Amiga systems are different (tower or desktop, highly or low expanded) and so they need different power supply units. An one-for-all is difficult or expensive to build. At least if you want ot have a good efficiency. On the other hand there exists PSU`s already (not plug`n play) but you have to search for one that match your needs. Unfortunately, some knowledge and rigs is required too.

[Kehil]

@thread, Jens: what tests would you recommend to perform in trial mode, to be sure that cpu frequency upgrade would be stable. Programs, duration... ? Thank you for suggestions.

[Schoenfeld]

Originally Posted by Kehil

@thread, Jens: what tests would you recommend to perform in trial mode, to be sure that cpu frequency upgrade would be stable. Programs, duration... ? Thank you for suggestions.

First of all: Close the A1200 trapdoor lid to *reduce* airflow around the CPU. Then generate a few AIBB modules (at least two), generate a huge LHA file in RAM: and test it over and over again. A simple script like

lab start
lha t ram:test.lha
skip back start

..will keep the CPU load at 100% over night. If the computer doesn't crash after you let it grind for half a day, I'd rate the CPU overclocking-stable.

Jens

[zekstra]

Anyone tried aca1221 with mediator?
Does it work?

[BertieWooster]

My aca1221 arrived today. I was pretty much certain that, with my luck, my A1200 would need the timing fix, but I breathed a huge sigh of relief when I got it running with no problems (so far). It seems to work flawlessly. Thanks Jens!

[TenLeftFingers]

I'd love to see how Frontier Elite runs on it compared to a stock A1200.

[eXeler0]

Originally Posted by TenLeftFingers

I'd love to see how Frontier Elite runs on it compared to a stock A1200.

Probably a bit less painful if you also overclock it, but IMO Frontier loves 50Mhz 030 or better..

[TenLeftFingers]

Originally Posted by eXeler0

Probably a bit less painful if you also overclock it, but IMO Frontier loves 50Mhz 030 or better..

No doubt. But after years playing it on a bog standard A600 it's possible this card will give it enough of a boost to still feel like an upgrade.

I'd love to see a video if anyone cares to make one.

[Schoenfeld]

Here's a nice opportunity to advertise for this card - Please, could an owner of the ACA1221 make such a video that shows the speed of the ACA1221@28MHz on this game, versus standard (card removed)? This should be possible with the trial jumper set.

Bounty: 28MHz overclocking code for that video.

Jens

[Kehil]

Two videos
Stock Amiga 1200 Frontier demo [ Show youtube player ]
ACA 1221@28MHz Frontier demo [ Show youtube player ]

edit: new side by side video here: [ Show youtube player ]

[Schoenfeld]

Thanks - the second video does look a lot better, especially when the "big mothership" is visible (around 2:55).

Could you please publish the two videos and link from one to the other? I guess creating a side-by-side version is too much to ask ;-)

Bounty granted - please eMail me.

Jens

[Kehil]

Links added. I'll try side by side during the evening and add it to the original post. Thank you a lot

[TenLeftFingers]

That is very impressive. I've just watched them in two browser windows side by side synced up to the 'David Braben' logo at the beginning. The difference is quite great between the two and with the ACA looks very smooth compared to the jerky unaccelerated version. Thanks to Jens and Kehil for the good spirit - I will definitely be ordering one of these boards.

[Amiga1992]

Originally Posted by TenLeftFingers

with the ACA looks very smooth compared to the jerky accelerated version.

What do you mean? What "accelerated version"?

That looks indeed very good, I don't know if I get the same performance out of my ACA620. Are there any benchmarks comparing the ACA620 to the ACA 122A?
Can the A620 be overclocked to 28Mhz?