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Re: REU for C-64 & C-128

Posted: Thu May 17, 2018 4:40 pm
by amigo-mexicano
Thanks for the info Nonefornow. I will check the link you posted!

Re: REU for C-64 & C-128

Posted: Sat May 19, 2018 1:33 pm
by eslapion
Nonefornow wrote: Wed May 16, 2018 4:00 pm I have given up on this. The guy that started the whole thing (in the other forum) had indicated that he received something like 10 e-mails from people showing interest. BTW - He never reply to my e-mails.

In any case I am now following this, which is already in development.. https://www.vintageisthenewold.com/rc20 ... nt-part-2/

It is not 16MB but .. 4MB in a real REU are better than 16MB in an imaginary REU.
It's my understanding GeoRAM is a considerably simpler RAM expansion than the Commodore REU.

Instead of using DMA, it offers a large number of pages of 256 bytes through the external IO areas. Not a very interesting RAM expansion IMHO.

Re: REU for C-64 & C-128

Posted: Sat May 19, 2018 7:06 pm
by Nonefornow
Well yes. Georam was the more affordable solution than the C1750 REU. Without DMA could not offer the speed and versatility of the C1570. It was basically just for GEOS. But it did not require the heavy duty power supply.
Realistically speaking there is not much more software to use with the C1570 so if the objective is to expand on GEOS, Georam is a valid alternative.

I was talking with the guy at GGlabs and I am not sure if there are any real benefits in having 4MB instead of 2MB. But other people seemed interested in the 4MB version.

GEOS will not use more than 2MB but GUI like Wheels and MP3 can take advantage of the extra ram.
Also, at least on a theoretical basis, this should offer better compatability to GeoRam than using the REU inside the 1541UII+.

Re: REU for C-64 & C-128

Posted: Sat May 19, 2018 8:23 pm
by eslapion
Nonefornow wrote: Sat May 19, 2018 7:06 pm Well yes. Georam was the more affordable solution than the C1750 REU. Without DMA could not offer the speed and versatility of the C1570. It was basically just for GEOS. But it did not require the heavy duty power supply.
Realistically speaking there is not much more software to use with the C1570 so if the objective is to expand on GEOS, Georam is a valid alternative.

I was talking with the guy at GGlabs and I am not sure if there are any real benefits in having 4MB instead of 2MB. But other people seemed interested in the 4MB version.

GEOS will not use more than 2MB but GUI like Wheels and MP3 can take advantage of the extra ram.
Also, at least on a theoretical basis, this should offer better compatability to GeoRam than using the REU inside the 1541UII+.
I beg to differ.

While there is a small but clearly present support for 1750/64 REUs with 512k or modded to carry more as well as the REU in the 1541 Ultimate series of carts (they use exactly the same mode of operation and control registers but they can offer up to 16MB), I don't know of anything at all which could use more than 512k on the GeoRAM architecture.

In fact, I don't know of anything other than GEOS itself which can use GeoRAM at all!

Re: REU for C-64 & C-128

Posted: Mon May 21, 2018 5:39 am
by Zippy Zapp
eslapion wrote: Sat May 19, 2018 8:23 pm In fact, I don't know of anything other than GEOS itself which can use GeoRAM at all!
That is the problem I see right there. I mean it is fine if all you want to use it with is GEOS. But the CBM REUs work with so much more. I use it frequently with not only GEOS but Maverick, BBS software, Terminal Software the occasional demo and a few other utilities that I have that take advantage of the 1764/1750. None of these will work with GEORAM. Don't get me wrong, I am not saying don't make it but it sure would be nice if a 100% compatible replacement could be made or the REU from the 1541U2 or Turbo Chameleon could be decoupled into a cost effective cartridge.

Re: REU for C-64 & C-128

Posted: Wed May 23, 2018 7:34 am
by ckoba
eslapion wrote: Sat May 19, 2018 8:23 pm In fact, I don't know of anything other than GEOS itself which can use GeoRAM at all!
My Infocom interpreters can use the GeoRAM. It's actually a little faster than using the REU. The banking scheme is the same as for EasyFlash.

Re: REU for C-64 & C-128

Posted: Fri Jun 01, 2018 12:10 am
by motrucker
Nonefornow wrote: Wed May 16, 2018 4:00 pm I have given up on this. The guy that started the whole thing (in the other forum) had indicated that he received something like 10 e-mails from people showing interest. BTW - He never reply to my e-mails.

In any case I am now following this, which is already in development.. https://www.vintageisthenewold.com/rc20 ... nt-part-2/

It is not 16MB but .. 4MB in a real REU are better than 16MB in an imaginary REU.
You do know that you can modify the Commodore 1750 to a 4Mb Max? I am currently using a 2Mb version of this project. GEOS will use all of this RAM (as RAM disks, of course). This is a very old idea, but it works until something better comes along.