A Hypothetical ROM Question

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gsmcten's picture
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A Hypothetical ROM Question

Hi All,

Besides my Apple II's I also dabble in the C64 computers.
By "Dabble" I mean that I have a couple but have yet to use them. lol

Looking at a majority of the early C64 software, it all seems to be on ROM chips placed in a cartridge.

I was thinking:

Would it be possible to place software on EPROMS and use the Integer ROM Card from an Apple II/II Plus
in Slot 7 to load programs?

Has someone else tried to do this before?

If they have, I have not heard of it.
If they have not, why not?

All input welcome.

Steven Smile

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Re: A Hypothetical ROM Question

Looking at a majority of the early C64 software, it all seems to be on ROM chips placed in a cartridge.

Well, yes and no. Lots of game software was put on cartridges for the same reason you find Atari 2600 games on cartridge - it's an easy way to distribute software that a) is foolproof, and b) is difficult if not impossible for the average consumer to copy. Much, much more software was distributed via disk, if you look more carefully.


Would it be possible to place software on EPROMS and use the Integer ROM Card from an Apple II/II Plus
in Slot 7 to load programs?

Yes, of course. Like the PET computers, some very early Apple II software was distributed via ROM chip that could be inserted right in the motherboard. One such example is the Woz Programmer's Aid #1 ROM (http://apple2history.org/history/ah03/).

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Re: A Hypothetical ROM Question

Not to forget the Apple Diagnostic Cards.....
In fact they are just cards that contain the testing program in the EPROMs
and start at bootup and then pickup results of the program right away from
the slots....

I have also similar Hardware for the Sinclair ZX81....
due to the fact that it usually had no Diskdrive at all and loading from
cassette port was timeeating and also resulted to errors i had a kind of
"basic programming system" in Eprom containing as simple editor and a
Z80 machinecode assembler so only assemled machine was demanding to be
saved or loaded from cassetterecorder. Later i added a adaptercard that
permitted either adding 6116 static RAM or 2716 Eproms to the system.
Later i modified the ZX81 itself by adding internal 3 time 6264 Static RAM:
http://www.appleii-box.de/ZX81/ZX8103intExpansions.htm

In a special kind of way you may also view to the Crackshot card or the Wildcard
same way like to the Programmers aid or the diagnostic card.....
Both contain programms to interrupt software by programm in ROM and then
dump the memory content to diskfiles.

Similar is valid to the AP64 from IBS Computer Systems.
It´s a Interface card that contains in the ROM ( Eprom ) the entire software for reading and writing Eproms.

So a program in ROM must not allways be a kind of game....
rather more often it´s cantaining programs for use with special hardware....
i.e. also measurementcards or cards for electrical engineering use at the Apple may be viewed at same aspect...

Also a similar kind of card for the Apple 1 is like this one:
http://www.appleii-box.de/A16_Apple1ROMexpansion.htm

so in fact the use of ROM / Eprom as storage device is only limited by space of the device and limitation
of phantasy...

speedyG
sincerely speedyG

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Re: A Hypothetical ROM Question

yes you can do it and there are real world examples.

Swyft card - this one is a custom card, but offers the same functionality as a firmware card, plus a little extra
The brainboard with Wozanium

If the program fits in 2K, it was very common to include functionality in the I/O space right on a peripheral card. I have some examples on my Superproto page.

The reason why it wasn't done more, is that floppy disks are vastly less expensive and don't use up precious slots. After 1978, virtually every Apple II had floppy drives, so why bother with hardware.

regards,
Mike Willegal

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Re: A Hypothetical ROM Question

Mike, Speedy, and David,

Thanks guys.

I knew about the items you mentioned, but It just struck me funny that
I have never heard of anyone trying this out the last few years
as a possible Hard Drive like the SD or CFFA Cards.

And I get the point about a ROM being limited for space.

Anyone else like to chime in?

Steven Smile

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