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echo: apple
to: comp.sys.apple2
from: BLuRry
date: 2008-08-07 04:45:00
subject: Re: Ideas for //c (rom 0) mods

On Aug 7, 4:36=A0am, "Michael J. Mahon"  wrote:
> > mega-huge transformer with a lot of wire coming off of it, goes
> > through the x-ray. =A0So I'd love to get rid of that part and lighten
> > the load a little (lot!)
>
> That surprises me, since all modern laptops--and almost everything
> else, too--has a "power brick". =A0Many printers have
"bricks" of similar
> size.
>
> Furthermore, what you will have inside the case will look very much
> like a power brick (though a switching one instead of a 60Hz
> transformer).

You're right, the similarity is there -- but a much smaller
transformer or switching power supply looks a lot more familiar and
less scary to those who didn't discover computers until the late
90's.  And most importantly should reduce the weight of the //c
considerably!

> I just recently went through security twice (in Seattle and Wichita)
> with a 17-board AppleCrate, packed in nested cardboard boxes with
> Masonite panels in between.

You're much braver than I.  I would have overnighted it.  I do not
trust baggage handlers or **gasp** other travelers who try to maximize
overhead bin space by smashing everything in their way.
> > -Which begs the question, are there any micro-controllers that emulate
> > floppies like SVD did? =A0Another totally kooky idea is something that
> > has the timing to emulate the boot 0 phase to push 256 bytes of loader
> > code into ram and execute a much cooler program that is less timing-
> > dependent and reuses the floppy signals to stream data in a way that
> > doesn't need to mimic physical media in favor of a larger storage
> > scheme based on IDE-style flash. =A0I think the only real barrier might
> > be the //c woz machine part. =A0Any way to bypass and go straight for
> > the raw signals?
>
> Sure, you can transfer data just like a smartport device.
>
> And the boot code can be any length that doesn't require a seek--
> which is not a problem if you're *emulating* a disk...

But the boot 0 is controlled by the woz machine and hence the //c rom,
right?  So is this possible without reprogramming the onboard rom?

>
> > -Pie in sky idea: Microdrive with a flash card that mounts in the
> > floppy drive opening. =A0Is there any way to tap the //c bus on a rom-0
> > board to create a virtual "slot"? =A0I seem to remember
that the //c ha=
d
> > its own rom that more or less occupied the bank-switch rom reserved
> > for physical cards in other ]['s, which leads me to believe that no
> > bankswitching =3D=3D no support for card rom =3D=3D no possibility to h=
ack a
> > slot. =A0Which is a bummer, but understandable.
>
> There should be pretty easy workarounds for ROM, since you will be
> changing it in any case. =A0All the signals needed for a slot are there
> or can be synthesized, so that should be possible.

Right, so you're saying this is doable if I pop the rom out and
reroute the traces accordingly.  Basically, making my own bankswitch
-- but where is it best to do this?  Hijack the processor or the rom
slot?  I'm certainly not opposed to re-learning what little I knew
about TTL logic! :-)

Thanks Michael!
-Brendan
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