Memory hacks . . .

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jt
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Memory hacks . . .

. . . RAM disks and maximum RAM configs for the Apple II series.

I usually do my own homework, but this is sort of a sideline interest for me . . .

. . . and since AF2.0 has close to ZERO activity lately, I'll just ASK for a change! Acute

Woogs told me NOT to hack my Laser 128, so I'll just have to max the sucker out. I'm buying the NASTIEST lookin' reworked IDE/Flash card the mfr. can dig up for this baby. It's got no internal memory expansion card soooo . . .

The expansion slot hanging off the left side is suddenly sporting a prototyping card that's been banging around in various boxes here since about 1990.

HEH! :ebc:

How much Memory can an A2 support and does anyone have links to the equivalent of DevNotes for the A2? I'm going to put an edge card socket on the protoboard (a few if I can get it to address more than 2 slots per the mfr's expansion box.) and there will very likely be a crapload of empty thruholes/prototyping space for a SIMM socket and conversion logic. Is the DRAM on older SIMMs compatible with the AII series memory type?

I'm a total n00b in this area, but I'll catch on eventually . . .

jt ::)

jt
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NUTS!!!!!!!!

. . . I for got the -bump- post trick and now my typos are preserved for posterity. Beee

Does the rolleyes emoticon show up correctly for anybody else, it looks like a : + a Smile in iCab under OS 9.

jt Beee

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RAM disk memory in an Apple II, Maximum?

Well, I guess the answer is; It depends.

6502 series processors can only access 64k RAM, but with bank switched memory, and your own custom controller/firmware, I suppose the sky could be the limit.

For practicallity, try an enhanced //e with an Apple issue 1 meg memory expansion card. ProDOS recognizes it, it has fast access, they are still obtainable (if you look REAL hard), etc. . .

Definitely get the IDE/Flash card reader too. It is awesome! Then you can access 4, 32MB partitions on a 128MB FC. Quiet, small, and solid state are hard to beat. And fast access time?!?! Wah-Hoo !!! And of course, you can make it your start-up "disk."

Mutant_Pie

jt
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Last seen: 17 years 9 months ago
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Re: RAM disk memory in an Apple II, Maximum?

Well, I guess the answer is; It depends.

6502 series processors can only access 64k RAM, but with bank switched memory, and your own custom controller/firmware, I suppose the sky could be the limit.

For practicallity, try an enhanced //e with an Apple issue 1 meg memory expansion card. ProDOS recognizes it, it has fast access, they are still obtainable (if you look REAL hard), etc. . .


PRACTICAL! :? Moi! HeHe! That's NEVER gonna happen! We're talking Laser 128 ALL the way here!

BTW, is the 1MB card the one with one bank of soldered 54256 DIP DRAM ICs and 3 banks of empty sockets . . . if so, I've got five of them, four brand new and one in my IIgs, IIRC. That's what I've been eyeballing to noodle our the req. for fanout/decoding/paging circuitry for something like an 8 MB SIMM.


Definitely get the IDE/Flash card reader too. It is awesome! Then you can access 4, 32MB partitions on a 128MB FC. Quiet, small, and solid state are hard to beat. And fast access time?!?! Wah-Hoo !!! And of course, you can make it your start-up "disk."

Acute Very nice! If that card supports ATAPI, that 5.25" FDD in the Laser 128 is HISTORY!

I just found a nice //c mouse for it, musta come with the IIgs.

jt :ebc:

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A2/LASER RAM

jt;

The cards that you are describing are the ones that
work in the stock Apple IIe series computers. That's
what I have in my 'hot-rod'. I don't know if that is
the limit, or if that is just the limits set by the
technology and programming of the time. (Remember, back
then 640K was the top limit for most software.) The IIgs
supports more than 1 MEG, so I think it would be possible
to do the same with an ordinary IIe or LASER type of
machine. Don't know/don't think that the old RAM cards
would support ATAPI. Same for the FlashCards. Maybe some
one else here has the answer to that? It would be really
neat to see a marriage between old-tech A2/LASER and new-
tech Flash Memory and mass storage! We've got some geniuses
here at this site that I'm sure have approached this in the
'Hardware Hack' section. I think you have the right approach
for the LASER! Get the most out of these old critters!

jt
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Hiya, woogs!

I couldn't find ANYTHING mentioning CD-ROM/ATAPI on the site or forums.

http://dreher.net/?s=projects/CFforAppleII&c=projects/CFforAppleII/main.php

I'll ask Rich when I email him again, but seeing as Flash/IDE appears to be an either-or proposition so far, I doubt the cards support ATAPI/CDs. That's OK though, because for the Laser it's actually just a research toy. What I REALLY want to do is develop similar NuBus/Bridged 030 PDS/Duo Docking Connector implementations of Flash/IDE AND ATAPI Opticals for 68k & NuBus PPC Macs & PBs. Rich moved on to PCs and has no plans to take his project in that direction, so I won't be stepping on his toes.

It should be fun . . . if maybe just a little bit less than sane . . . :ebc:

jt Smile

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