Apple IIc modifications

[Sam Latella]

Hi,

What modifcations can you do on a standard Apple IIc? I just purchase an
Apple IIc and am still amazed by how portable it is even after 20 years. I
tested the machine with a 55 inch LED TV and WOW! I am reallly going to
enjoy watching my kids play educational games from the Apple II era on a
modern 55 inch Samsung TV. I gues the knew meets the old!

So, back to modifying the IIc. I've read somewhere that you can mod it to
work with 3.5 inch drives is this easy to do? I've got basic experience
replacing chips, installling cards, and hard drives. Soldering is not my
forte at all.

Besides getting a Zipchip. I'm more interested in a cheap alternative of
getting a 3.5 inch drive to work with the IIc.

Any other mods I've missed for the IIc. Would like to hear them.

It's to bad Apple never went the route of the IIc for the IIgs it would have
been a winner, and very neat portable alternative for the Apple II line.
For now I'll stick to having fun on the IIc with the kids.

Thank-you for your time,
Sam

[Sean Fahey]

Your //c might already be compatible with the UniDisk 3.5 drive.

At the BASIC prompt, type: PRINT PEEK (64447)

If it returns 0, 3 or 4 then you have a compatible machine. If it says '255' then you have the original ROM and can't use one.

It may be cheaper and easier to buy an Apple IIc Plus which has a built-in 3.5 drive and runs at 4MHz (or faster when overclocked) than to acquire a ZipChip and external UniDisk 3.5 drive.

[Warren Ernst]

FYI, the majority of kids games / educational games work just fine at
the stock 1mhz, and most of the 8-bit kids games come on 5.25" disks.

-Warr

[sporadic]

I recently picked up a couple of IIc+ off eBay, and you really need the external 5.25" drive to be useful. Unless you're looking to run AppleWorks, in which case the built-in 800K 3.5" floppy and 4MHz would be better than the original IIc.

And as Sean pointed out, it might be cheaper to just get a IIc+ than to retrofit a IIc with 3.5" and a ZipChip (a rare item).

Jimmy

[Bill Garber]

"sporadic" <sporad...@gmail.com> wrote in message news:32669017.475.1319819159350.JavaMail.geo-discussion-forum...

That 3.5" Unidisk drive is fairly rare itself, not quite as
rare as the ZipChip, but also goes for quite a hefty amount
when one does come up.

Bill

[Steven Hirsch]

On 10/28/2011 12:25 PM, sporadic wrote:

> And as Sean pointed out, it might be cheaper to just get a IIc+ than to
> retrofit a IIc with 3.5" and a ZipChip (a rare item).

And, for even more computing pizazz you can hotrod many IIc+ machines to
double the clock speed (or more?). Word of warning: Do not make removal and
replacement of the can oscillator your first soldering experience :-). It's
not rocket science, but you'll be working with a double-sided board that
requires a bit of finesse.

Steve

[Michael Black]

That doesn't impact on other things in the IIC? (I have no idea.)

I got my OSI Superboard 30 years ago next month, I couldn't afford an
Apple II at the time. And I don't recall it being that much time after I
had it that I modified it so it would run at twice the original clock
speed, so it was running at 2MHz. Right away I could see the snap in the
system, it wsa only twice the speed and pretty slow speed to begin with,
but that really was a noticeable change.

Now it's really hard to double the speed of a current CPU, and I'm not
sure one would really notice the change.

Michael

[Steven Hirsch]

On 10/28/2011 04:22 PM, Michael Black wrote:
> On Fri, 28 Oct 2011, Steven Hirsch wrote:
>
>> On 10/28/2011 12:25 PM, sporadic wrote:
>>
>>> And as Sean pointed out, it might be cheaper to just get a IIc+ than to
>>> retrofit a IIc with 3.5" and a ZipChip (a rare item).
>>
>> And, for even more computing pizazz you can hotrod many IIc+ machines to
>> double the clock speed (or more?). Word of warning: Do not make removal and
>> replacement of the can oscillator your first soldering experience :-). It's
>> not rocket science, but you'll be working with a double-sided board that
>> requires a bit of finesse.
>>
> That doesn't impact on other things in the IIC? (I have no idea.)

I'm referring to IIc+ and, no, it does not. The IIc+ has essentially an
embedded ZipChip 4000 (4Mhz.). Increasing the core CPU clock has no effect on
anything else, since it's throttled back to 1.x Mhz. for timing-sensitive
diskette routines, etc.

> I got my OSI Superboard 30 years ago next month, I couldn't afford an Apple II
> at the time. And I don't recall it being that much time after I had it that I
> modified it so it would run at twice the original clock speed, so it was
> running at 2MHz. Right away I could see the snap in the system, it wsa only
> twice the speed and pretty slow speed to begin with, but that really was a
> noticeable change.

It will be quite noticeable on a IIc+.

> Now it's really hard to double the speed of a current CPU, and I'm not sure
> one would really notice the change.

Even if you did, the next release of $OPERATING_SYSTEM would be yet more
bloated and offset the potential advantage :-).

Steve

[Kevin Dady]

Not to be a buzzkill and this is just my opinion but the 800k 3.5 inch
disk is a pain in the ass and personally not worth the trouble. Its a
variable speed format that only apple used, so its not like you can
just pop a disk in your PC and copy files over to it, heck even my
powermac 9600 is a little weird making prodos disks.

The majority of apple II software is in 5.25 format so if the software
allows it the best you might be able to do is make a "mix tape" of
stuff.

Finally you can hardly find HD 1.4mb disks now let alone DD disks so
your going to have to order them, at that point once you get disks
ordered and shipped, a computer that can actually read the silly
things in apple format, and fuss with making a mix disk you might as
well just get a box of 5.25 DD disks and use as normal, or use
something like apple game server for the programs that load fully in
ram ... killing the need for floppies anyway.

Grats on your IIC, I have one as well and its a fun computer just as
all apple 2's without needing a bunch of space, which is nice though I
wish it had a slot sometimes

[Egan Ford]

> Finally you can hardly find HD 1.4mb disks now let alone DD disks so
> your going to have to order them, at that point once you get disks
> ordered and shipped, a computer that can actually read the silly
> things in apple format, and fuss with making a mix disk you might as
> well just get a box of 5.25 DD disks and use as normal, or use
> something like apple game server for the programs that load fully in
> ram ... killing the need for floppies anyway.

You can cover the hole on a HD disk and use as a DD disk. I do it all
the time without any issues.

That said, I completely agree with your assessment.

I'll also add that if I want to play II games on the big screen with
minimum fuss, then I'll use an emulator.

[Michael J. Mahon]

Apparently it's been a while since this topic came up here...

HD 3.5" disks are _not_ reliable media for Apple's DD drives. They may
appear to work for a while, but not uniformly on all drives, and after some
time they often lose data, becoming unreadable.

DD disks are still available and are the _only_ reliable media for Apple II
drives (except, of course, the Apple 3.5 "SuperDrive", which requires a
special controller).

-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon

[D Finnigan]

Michael J. Mahon wrote:
> Egan Ford <data...@gmail.com> wrote:
>>> Finally you can hardly find HD 1.4mb disks now let alone DD disks so
>>> your going to have to order them, at that point once you get disks
>>> ordered and shipped, a computer that can actually read the silly
>>> things in apple format, and fuss with making a mix disk you might as
>>> well just get a box of 5.25 DD disks and use as normal, or use
>>> something like apple game server for the programs that load fully in
>>> ram ... killing the need for floppies anyway.
>>
>> You can cover the hole on a HD disk and use as a DD disk. I do it all
>> the time without any issues.
>>
>> That said, I completely agree with your assessment.
>>
>> I'll also add that if I want to play II games on the big screen with
>> minimum fuss, then I'll use an emulator.
>
> Apparently it's been a while since this topic came up here...
>
> HD 3.5" disks are _not_ reliable media for Apple's DD drives. They may
> appear to work for a while, but not uniformly on all drives, and after
some
> time they often lose data, becoming unreadable.
>

This is the part where I dance in and state that I have several HD disks
which I formatted as 800k for the IIgs back in 2004-05, which still work
today.

Yeah, I've read the warnings, but it'll never happen to me!

:-D

--
]DF$
Mac GUI Vault - A source for retro Apple II and
Macintosh computing.
http://macgui.com/vault/

[Bill Garber]

"D Finnigan" <dog...@macgui.com> wrote in message news:dog_cow-1...@macgui.com...

> Michael J. Mahon wrote:
>> Egan Ford <data...@gmail.com> wrote:
>>>> Finally you can hardly find HD 1.4mb disks now let alone DD disks so
>>>> your going to have to order them, at that point once you get disks
>>>> ordered and shipped, a computer that can actually read the silly
>>>> things in apple format, and fuss with making a mix disk you might as
>>>> well just get a box of 5.25 DD disks and use as normal, or use
>>>> something like apple game server for the programs that load fully in
>>>> ram ... killing the need for floppies anyway.
>>>
>>> You can cover the hole on a HD disk and use as a DD disk. I do it all
>>> the time without any issues.
>>>
>>> That said, I completely agree with your assessment.
>>>
>>> I'll also add that if I want to play II games on the big
>>> screen with minimum fuss, then I'll use an emulator.
>>
>> Apparently it's been a while since this topic came up here...
>>
>> HD 3.5" disks are _not_ reliable media for Apple's DD drives.
>> They may appear to work for a while, but not uniformly on all
>> drives, and after some time they often lose data, becoming
>> unreadable.
>
> This is the part where I dance in and state that I have
> several HD disks which I formatted as 800k for the IIgs
> back in 2004-05, which still work today.

I have a few that worked, a few that did not.

> Yeah, I've read the warnings, but it'll never happen to me!

I heeded the warnings somewhat, making sure that I had backups
of the stuff I put on them, so that I'd be able to recover had
they succumbed to the curse of the warnings given.

> :-D

<[8o}

Bill

[Tony Cianfaglione]

On Sat, 29 Oct 2011, Michael J. Mahon wrote:

> Apparently it's been a while since this topic came up here...
> HD 3.5" disks are _not_ reliable media for Apple's DD drives. They may
> appear to work for a while, but not uniformly on all drives, and after some
> time they often lose data, becoming unreadable.

I have used several hundred HD disks formatted as DD in my IIc, IIc+
and GS for over 25 years and have never had a file or disk failure. It
was pure economics which forced me to use them originally as DD disks
often sold, locally, for a lot more than HD disks and, as DD disks became
scarcer, the price divide grew.

When I first heard of this controversy, I formatted and filled up a
bunch of test disks, and packed them away, to see if they would, maybe,
fail with non-use. I'm happy to report that, after 25 years, of both the
non-use disks and the ones I use regularly, there has never been a
failure. It's possible some early HD disks were inferior and failed on
someone, and that may have started the whole disk warning controversy.

It's the same way with the Apple IIc 1mb expansion card, which is not
supposed to work in a IIc+, yet mine has been purring along nicely for 20
years and I use all my Apple II's daily, event to write this email. Now
HD 5.25" disks are different story. These will definitely not work at
all; never have, never will.

An amusing aside: A couple of years, I was doing a demo for our local
PC users' group and I showed off a 5.25" disk notcher, which our platform
used to create 'flippies' from floppies (I know, that's a whole other
controversy there), and the PC guys were absolutely amazed at the device,
never having needed one for their HD 5.25" disks. I even have a 3.5" disk
notcher for turning DD disks into HD disks. That's quite a device but the
resulting disks work well - surprisingly. I got that device from my Amiga
friends.

Tony

[Wholly Mindless]

Can we at least make sure that we document that for *some* people 3.5" HD
disks DO NOT ALWAYS work? That way when someone finds this at 3am after a
Walgreens run and is frantically trying to format the box of 10 they bought
and they start looking on the net, they don't assume their drive is bad and
start tearing it apart?

My experience has definitely been down in the 1 of 10 or maybe even less
work. It is also possible that newer drives (or older drives for that
matter) are more tolerant. We just haven't done definitive research - or at
least most of us haven't.

--
Wholly

[Sam Latella]

Thanks to everyone with the quick response! I check out a few suggestions.
I was curious as to an easy way of loading up many Apple II educational
games for the kids instead of via floppy. Looks like I'll have to setup
Apple II games server on a win laptop and connect to the IIc.

Sam

[Egan Ford]

On Oct 30, 4:25 am, powe...@macgui.com (Sam Latella) wrote:
> Looks like I'll have to setup
> Apple II games server on a win laptop and connect to the IIc.

How exactly? Just curious.

[Kevin Dady]

There is a program called apple game server, which works like
bootstrapping with ADT, so if you have a program that runs entirely
from memory you can dump it direct via serial ports.

for an easy apple IIC serial cable I went to radio shack, you can get
the DE9F connector, a decent plastic or even metal hood and a 6 foot
midi cable, chop off the end wire appropriately and it looks factory

[Michael J. Mahon]

The difference in coercivity of HD vs. DD media is much less for 3.5"
diskettes than it is for 5.25" diskettes, so _some_ drives will be able to
write to them well enough, but HD media is outside the tolerance for DD
media, so no DD drive was designed to write it to saturation (or erase
previously written data, either). You can apparently find DD drives that
can write reliably, but that's depending on luck, not on proper design
margins.

Proper design margins are the only thing that allows us to treat the analog
world as if it were digital.

If the media is not written (magnetized) to saturation, then the domains
storing the data have a greater tendency to decay, resulting eventually in
unreadable data.

Note that it's the writing that's the issue. Once a diskette is stably
written, any drive should be able to read it.

In the case of 5.25" diskettes, the coercivity of HD media is so much
greater than DD that HD diskettes are universally unusable.

[Mark Frischknecht]

You are inviting disaster by using 3.5 HD disks as DD disks.
As I have told people before in other places:

Never use 1.44 as a 800k....
1.44 meg disks need a stronger magnetic field to set the bits and
formatting it as 800k the floppy heads use a weaker magnetic field
which will cause corruption. And the bits on the disk will rapidly
revert to the original random alignment.

DSDD 3.5 has a Coercivity of 600 osterads
DSHD 3.5 has a Coercivity of 720 osterads

Higher coercivity means a stronger magnetic field is needed to set the
bits, and a 800k drives or a 1.44 drives formatting in 800k mode do not
have a strong enough magnetic field to properly set the bits.

It may seem to work but in the end it will fail.

V/R

Mark Frischknecht

[Mark Frischknecht]

ps here is a intresting read on why not to use HD disks as DD disks
http://www.retrotechnology.com/herbs_stuff/guzis.html

[Tony Cianfaglione]

On Mon, 31 Oct 2011, Mark Frischknecht wrote:

> It may seem to work but in the end it will fail.

Gee, Mark... I've been using them repeatedly in my II's for over 25
years - when does the end come?

[Mark Frischknecht]

Probably when it is most inconvenient. I have seen the problem happen,
at Kfest a programmer was handing out copies of software h programed
on 3.5 HD disks formatted as 800k and none of the disks were readable.
So please keep your sarcastic comments to yourself.

V/R

Mark Frischknecht

[David Schmidt]

On 10/31/2011 6:46 PM, Mark Frischknecht wrote:
> On 2011-10-31 21:10:21 +0000, Tony Cianfaglione said:
>
>> On Mon, 31 Oct 2011, Mark Frischknecht wrote:
>>
>>> It may seem to work but in the end it will fail.
>>
>> Gee, Mark... I've been using them repeatedly in my II's for over 25
>> years - when does the end come?
>
> Probably when it is most inconvenient. I have seen the problem happen,
> at Kfest a programmer was handing out copies of software h programed on
> 3.5 HD disks formatted as 800k and none of the disks were readable.

That's the thing: as another poster pointed out, it seems to be
particular to the drive. Perhaps Tony's drive is one of those
highly-capable ones. I've not been lucky, myself. Generally, the disk
will fail immediately after writing - so I just don't do it.

[Tony Cianfaglione]

On Mon, 31 Oct 2011, Mark Frischknecht wrote:

> Probably when it is most inconvenient. I have seen the problem happen, at
> Kfest a programmer was handing out copies of software h programed on 3.5 HD
> disks formatted as 800k and none of the disks were readable. So please keep
> your sarcastic comments to yourself.

It's possible that my drives are running at a slightly higher power
level as I use custom made power supplies which push out a bit more juice.
Maybe this is resulting in better results for me in this regard. I'm not
being sarcastic; it's just that I've had very good results with HD disks
as DD disks for a quarter century.

[Mark Frischknecht]

Np sorry about snapping at you I had just gotten home form a 7:00 pm tp
7:00 am shift at Intel..

[Kevin Dady]

not to nitpick but supplies dont push, they provide, ie you hook a 1
amp load to a 0.5amp supply, its going to provide 1 amp as that is
what the circuit consumes, which could cause your supply to simply
overheat and shut down, or if its big iron and coils, melt down and
burn up. Likewise if your circuit is only drawing 0.5 amp's you could
hook a 500 amp battery to the thing and its still only going to use
0.5 amps.