Autor Wątek: Karabas-128 - ZX Spectrum 128k clone  (Przeczytany 16862 razy)

andykarpov

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    Nikopol, UA
    • Andy Karpov's github projects
Odp: Karabas-128 - ZX Spectrum 128k clone
« Odpowiedź #165 dnia: 2020.06.01, 00:33:08 »
Thanks! It's seems the same chip used in the ZX-UNO VGA2M. Not so cheap, but probably less rare ;)
My retrocomps: Karabas-128 rev.B1, Karabas-Nano rev.D, Buryak-Pi 2019, ZX-Evolution rev.C4, Profi 5.06, Harlequin 48k rev.G, Harlequin 48k rev.H, Reverse-U16 rev.C, DivGMX, Aeon Lite, MiST, Galaksija SMD, UT-88

Maryjan

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Odp: Karabas-128 - ZX Spectrum 128k clone
« Odpowiedź #166 dnia: 2020.06.01, 11:21:42 »
Will the 1 Mb ram version be developed?

"... podobno są dwie szkoły, Falenicka i Otwocka."

andykarpov

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  • Wiadomości: 37
  • Miejsce pobytu:
    Nikopol, UA
    • Andy Karpov's github projects
Odp: Karabas-128 - ZX Spectrum 128k clone
« Odpowiedź #167 dnia: 2020.06.02, 19:50:39 »
Hehe, i think the 1mb option is not so important and useful today, really. There are more problems with that extended memory than profits. Also it depends by which standard the external ram will be mapped. As you may know, there are at least 3 (really - much more) different incompatible standards (pentagon via port #7ffd, profi via port #dffd, pentagon via service ports #1ffd, #7ffd, scorpion, etc, etc).  So, i'm pretty sure nobody needs that. Also, the old software that uses access to port #7ffd via a short name (#fd) will be totally incompatible with any extram standards, that's why almost all ex-USSR speccies has a hardware switch to disable any extram options ;) Also, i think - there is no reason to have that extended ram at all. In that old times it was useful for the RAM-discs to simplify handling of disk images under TR-DOS. Currently we all have DivMMC that works independently and pretty nice, so 128k will be enough for all, still ;)
My retrocomps: Karabas-128 rev.B1, Karabas-Nano rev.D, Buryak-Pi 2019, ZX-Evolution rev.C4, Profi 5.06, Harlequin 48k rev.G, Harlequin 48k rev.H, Reverse-U16 rev.C, DivGMX, Aeon Lite, MiST, Galaksija SMD, UT-88

Maryjan

  • *****
  • Wiadomości: 5323
  • Miejsce pobytu:
    Skarżysko-Kam.
  • Scotch whiskey and West Highland Terrier
Odp: Karabas-128 - ZX Spectrum 128k clone
« Odpowiedź #168 dnia: 2020.06.02, 21:21:12 »
Actually, every user would have to program such memory themselves. It does not make sense. It is better to stay at 128kb RAM
"... podobno są dwie szkoły, Falenicka i Otwocka."

andykarpov

  • *
  • Wiadomości: 37
  • Miejsce pobytu:
    Nikopol, UA
    • Andy Karpov's github projects
Odp: Karabas-128 - ZX Spectrum 128k clone
« Odpowiedź #169 dnia: 2020.06.04, 17:06:23 »
What about AS7C4096A-12TIN? This SRAM chip is 5V compatible and in TSOP 2 package.

Added a TSOP-I 48 Cypress SRAM CY62167 into the new revision rev.G of the karabas-nano. Feel free to try. This chip works nice with karabas-nano, my friend already tested it on a breadboard ;) There are also a few minor changes in that revision. like SD connector is now Molex 49225-0821, i like them so much. Also a smaller buttons and some routes refactoring. Due to another pin mapping, that rev.G is not compatible with older revisions, so i will add a separate firmware for each revision since now.






My retrocomps: Karabas-128 rev.B1, Karabas-Nano rev.D, Buryak-Pi 2019, ZX-Evolution rev.C4, Profi 5.06, Harlequin 48k rev.G, Harlequin 48k rev.H, Reverse-U16 rev.C, DivGMX, Aeon Lite, MiST, Galaksija SMD, UT-88