Re: Need card Identified, please.

["Michael J. Mahon" <mjmahon@aol.com>]

Bill Garber wrote:
> "Michael J. Mahon" <mjmahon@aol.com> wrote in message
> 2K-dnfsMY6yfLNHfRVn-qQ@comcast.com">news:2K-dnfsMY6yfLNHfRVn-qQ@comcast.com...
> : Bill Garber wrote:
> :
> : <snip>
> :
> : > It appears that it's a ROM card. You either write your ROM to
> : > the 6116 ram and back it up with the rechargeable batteries,
> : > or you can burn eproms and insert them. If I can adapt it to
> : > larger ram or Eproms, then it will be a nice card. Otherwise,
> : > I have a FlashROM card that can go up to 512K easily enough.
> : > What good is 16K in this day and age, when larger ROM cards
> : > are possible??  :o)
> :
> : The capacity limit will depend on the decoding and bank
> : select logic on the board.
> :
> : Given that it was intended for 2KB EPROMs/SRAMs, it would
> : be surprising if it went much beyond that.
> :
> : All addressing of the on-card memory must be "windowed"
> : into, I would guess, the 2KB I/O extension space on the
> : Apple II, from $C800 to $CFFE.
>
> Sounds right, except that the switches might select which
> 2K area is active, or be setting how many 2K areas are active.
> We'll know more once the Docs are translated to English.
> Assuming the number of people who have downloaded them is
> correct, then I believe I should have OCR'd copies, and possibly
> translated copies in a day or two. If so, thank you to whomever
> is doing so.  :o)

The DIP switches may set some default, but it would be much
handier if all ROM enabling were controlled by bank select
logic manipulated by software--which I expect is the case,
because of the other chips on the card.

What the card probably doesn't support is mapping ROM/RAM
larger than 2KB in "pages" to the windowed address space,
which would make any size ROM/RAM inserted look like 2KB,
at most.

-michael

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