AA3000+ Accelerator

[nyteshade]

Hey folks. I have a A3660/50 but I’m seeking an accelerator that has accelerator RAM (for speed) and the A3660 does not. What should I be looking for?

I have a Hese built AA3000+.

Thanks,
Brielle

[TjLaZer]

Wait for the TF4060 card.

https://www.retrounlim.com/2022/04/2...r-a3000-a4000/

[Hedeon]

There is an memory adapter in the works for the A3660. Haven't seen updates recently, though

[trixster]

I’ve got two of those A3660 memory boards being built up at the moment. Doubt they’ll work in an AA3000+ though (or 3000 or 4000T) due to scsi / no dma issue. So 4000D only.

[trixster]

Originally Posted by TjLaZer

Wait for the TF4060 card.

https://www.retrounlim.com/2022/04/2...r-a3000-a4000/

Or Matze’s new card. Word is the pcbs and BOM will be released this month

[nyteshade]

Originally Posted by nyteshade

Hey folks. I have a A3660/50 but I’m seeking an accelerator that has accelerator RAM (for speed) and the A3660 does not. What should I be looking for?

I have a Hese built AA3000+.

Thanks,
Brielle

Thanks everyone. As far as A4K vs A3K it’s hard to tell how much if any DMA is supported given it’s half an A4K

[Jope]

Originally Posted by nyteshade

Thanks everyone. As far as A4K vs A3K it’s hard to tell how much if any DMA is supported given it’s half an A4K

The DMA problem is with the A3660's RAM board. The AA3000++ SCSI will stop working if you don't have a DMA capable CPU card.

[nyteshade]

Wow I did not know that! Thanks.

[Kin Hell]

Originally Posted by nyteshade

Thanks everyone. As far as A4K vs A3K it’s hard to tell how much if any DMA is supported given it’s half an A4K

Half an A4K!

Damn it man....It's everything the A4K should have been when it was released.

Onboard SCSI, DSP Sound, PCI, blah blah blah...

I'd be leaning more towards Hese's AA3000+ being at least 1.5 x an A3000, maybe 2.0

Half indeed!

[alexh]

Originally Posted by Jope

The DMA problem is with the A3660's RAM board. The AA3000++ SCSI will stop working if you don't have a DMA capable CPU card.

This is quite likely a SW issue and might be possible to fix by modifying the A3000 SCSI driver in Kickstart ROM.

There were similar issues with the CDTV CD-ROM driver where it requested memory for DMA buffers but didn't specify it needed 24-bit DMA capable memory.

It was possible to HEXEDIT the driver find the AllocMEM calls and add MEMF_24BITDMA to the call.

[nyteshade]

You guys are awesome. Thank you.

[Leon Besson]

Originally Posted by nyteshade

You guys are awesome. Thank you.

That’s what they do Mang! One of the reasons I joined on here

[Jope]

Originally Posted by alexh

This is quite likely a SW issue and might be possible to fix by modifying the A3000 SCSI driver in Kickstart ROM.

DMA to chip RAM or Z2 RAM (if installed) will probably work by setting a narrow mask for the partitions.

I don't know enough about the super dmac to know whether it is possible to do PIO transfers with it.

[alexh]

Originally Posted by Jope

DMA to chip RAM or Z2 RAM (if installed) will probably work by setting a narrow mask for the partitions.

Yes I forgot about that. The right mask setting in HDtool box when partitioning the drive might prevent the driver trying to DMA outside of DMA capable RAM.

That wasn't possible with the CDTV CD-ROM driver

[nyteshade]

Who has more info on that bit?

[alexh]

Originally Posted by nyteshade

Who has more info on that bit?

What bit?

[Kin Hell]

Originally Posted by alexh

What bit?

Originally Posted by Jope

DMA to chip RAM or Z2 RAM (if installed) will probably work by setting a narrow mask for the partitions.

I don't know enough about the super dmac to know whether it is possible to do PIO transfers with it.

Originally Posted by alexh

Yes I forgot about that. The right mask setting in HDtool box when partitioning the drive might prevent the driver trying to DMA outside of DMA capable RAM.

That wasn't possible with the CDTV CD-ROM driver

Originally Posted by nyteshade

Who has more info on that bit?

Maybe the Bold Bits....

[nyteshade]

The proper mask settings. Of course.

[alexh]

Originally Posted by nyteshade

The proper mask settings. Of course.

The HDToolbox mask is IIRC 1-bit for every bit of a 32-bit memory space. So by setting only 24-bits you're guaranteeing that the OS filesystem will never make DMA buffers outside of Chip/Motherboard Fast/ZorroII Fast RAM.

0x00FFFFFC

[SpeedGeek]

First, this thread is off topic here and should be moved into support.hardware. Hopefully, a GM will do that for us.

Second, I hate to rain on the parade here, but if your proposed mask solution would have worked for the X-Calibur, then don't you think someone would have reported this by now?

http://amiga.resource.cx/exp/xcalibur

The problem with mask is it only affects filesystem transfers. But what about SCSI direct transfers? In particular, reading the RDB from the drive, which of course needs to be done first in order to boot from the drive.