exxos's Atari, Amiga & retro forum

Can I use the 2021 adapter board only as a 16 MHz CPU booster? I have the 6 chip 1.04 ROM chips from your store already installed and I'm not really that interested in the dual tos functionality for now at least. Sorry if this info is available somewhere but I looked around a bit and didn't see anything.

Basically you can use the booster without dualtos....

The booster will still decode ROM faster ,so you still need fast ROMs. But if the ROMs are from more my store then they are generally fast enough for just using TOS104 6chip at 16mhz anyway.

Ok perfect! Aye it's the ROMs with the fancy rainbow TOS stickers from your store. Thanks for the quick reply. :)

Then I guess I just have to figure out where to connect the ROM CE signal on the bare motherboard? Would that be on U68 somewhere? Or on the glue chip? Sorry I'm not that great with schematics yet. It's a 70789 type board but a later model with the SMT GLUE/MMU chips.

You don need to connect ROM CE.

Ah ok, that had me a bit confused. Even simpler then! Thanks again for your help. :D

@exxos So do you have any figures for which speed grade of EPROMs you need for the booster @ 16MHz?

I'm thinking of using one of your 16MHz booster/TOS decoder boards on an H4/H5 & have some 90ns Atmel OTP EEPROMs that I could use (if they would be fast enough)...there are some 55ns parts on their way to me (apparently) if the 90 are not fast enough.

TIA

100ns I know works for 16mhz. 120ns and slower might but I've never tried or bought slower ROMs .

55ns or faster is mostly for the STE when running the 32mhz booster.

Thanks @exxos !

Perfect.

So now I already ordered this earlier and should have probably asked this before ordering, but I have a blitter installed in the STFM. Will the booster work fine with that? I assume it won't actually boost the blitter clock but it should still work fine I hope?

krs wrote: 06 Sep 2023 20:05 So now I already ordered this earlier and should have probably asked this before ordering, but I have a blitter installed in the STFM. Will the booster work fine with that? I assume it won't actually boost the blitter clock but it should still work fine I hope?

The booster was designed with the blitter in mind. It doesn't boost the blitter because thats a RAM thing which can't been speeded up.

There are benchmarks from a previous gen booster here.

https://exxosforum.co.uk/atari/last/V23 ... /index.htm

I think I did experiments trying to speed up the blitter for ROM access years ago, but IIRC made no odds.