Re: Apple //c++ experiments...

[John <zzzjoki@yahoo.com>]

On Aug 12, 5:53 am, "William Garber" <willy4...@garberstreet.com>
wrote:
> "John" <zzzj...@yahoo.com> wrote in message1186900255.701363.179420@q3g2000prf.googlegroups.com">news:1186900255.701363.179420@q3g2000prf.googlegroups.com...
>
> : On Aug 11, 4:37 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
> : > I recently acquired a //c+ (Yay!), so I decided to try replacing the
> : > 16MHz accelerator oscilator with a 32MHz oscillator to bump the speed
> : > from 4MHz to 8MHz (making it a "//c++"  ;-).
> : >
> : > I was concerned that simply replacing the oscillator might shorten
> : > the "slowdown" times for slow slots and the speaker and joystick,
> : > which could pose a problem.
> : >
> : > The answer is that the slowdown times are timed by counting down
> : > the 1MHz Apple bus clock, not the accelerator clock, so they are
> : > unaffected by oscillator frequency--a very convenient result.
> : >
> : > Also, the Zip Chip Utilities, and in particular the ZIP.SYSTEM program
> : > that runs before any other system program on the boot volume, configures
> : > the IIc+ just as it would for any slotted Apple II.  Of course, it is
> : > necessary to leave slots 5 and 6 slow for disk access to work, and in
> : > the IIc+ it does not appear to be possible to set the joystick to
> : > "fast" (but the speaker can be set to fast).
> : >
> : > In short, just replacing the 16MHz oscillator with a 32MHz oscillator
> : > converts a IIc+ into a "IIc++", and the Zip utilities can be used to
> : > configure the actual speed, or even to default the accelerator to "off".
> : >
> : > BTW, I understand that some IIc+ machines will not run with a 32MHz
> : > oscillator.  I have several 32MHz oscillators, and found that one type
> : > would not work, while another (RXD 1100) did, so maybe the problem
> : > some have reported is an oscillator problem, not a IIc+ problem...
> : >
> : > I tried a 39.750MHz oscillator, and it didn't work--but it was of the
> : > same type that did not work at 32MHz, so I don't think that proves
> : > anything.  I was hoping it would work, so that I could run at 32MHz
> : > with some assurance of some "headroom" for reliability...
> : >
> : > -michael
> : >
> : > NadaNet file server for Apple II computers!
> : > Home page:  http://members.aol.com/MJMahon/
> : >
> : > "The wastebasket is our most important design
> : > tool--and it's seriously underused."
> :
> : I just got one of these last week. Can one add a HD somehow, too?
> :
> : I didn't get any utilities or any disks. Are these online
> : (zip control I guess, if I understand your post)?
>
> These utilities are now available on my website under
> the 'DSK Images' folder, called "ZIP CHIP II.dsk".
>
> ENJOY!!!
>
> Or, you can use this handy link.  :o))))))
>
> http://www.garberstreet.com/Apple2/DSK%20Images/ZIP%20CHIP%20II.dsk
>
> William Garber
> Email Address - willy4...@garberstreet.com
> Alt. Email - willy4...@comcast.net
> Web address -http://www.garberstreet.com

Thank you. I got it!