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IIc vs IIc+

senrew

Well-known member
My current goal is to replace my IIgs for a smaller IIc of some kind. I really have no need fo rthe 16-bit or GS/OS software that is available for the newer machine. My intentions are to use it as a hobby programming platform and to just dick around with old 8-bit games specifically.

From a usability standpoint, is there any real benefit to a plus over a regular IIc? The larger capacity drive and the more modern serial ports are really the only things I can think of that might be useful to me, but those are easily gotten around. 

 

Elfen

Well-known member
There are major differences between the IIc and the IIc+. And there are 2 versions of the IIc itself.

The biggest is the PSU. In the IIc+, the Power supply is internal to the IIc+ and plugs into the wall directly. The IIc has a simple step down transformer to bring 120VAC down to 12V DC, and that goes into a power regulator board inside the IIc. This, strangely enough, allows the IIc to be powered by a 12V battery if you can rig up power jack for it.

The first (older) version of the IIc has few options to upgrade. you got 128K, 2 serial ports, floppy port, video, etc. and that's it. If you more RAM, lets say, you have to get a specific board and hard wire it in. The second (newer) IIc has a RAM Expansion port, as does the IIc+. This allows you to plug in a RAM Board and even a Z80 Card into the IIc; they are made by Applied Engineering and other companies and lets you have up to a Meg of RAM into the IIc.

The serial ports on the IIc+ uses the standard Din 8 ports used on the Macs. The ports on the IIc uses Audio style Din 8 pin Jacks.

The Disk Drive is different, as the IIc uses the "standard" 5.25 inch drive and the IIc+ uses the 3.5 in drive. This is the same 3.5 inch drive used in the IIgs. The IIc+ can use a 5.25 drive you plug in to the back, like the IIgs. And here is where is gets tricky. The older first version of the IIc only uses the 5.25 inch drives; the second newer version of the IIc can use both 5.25 inch and 3.5 inch drives.This is because the IWM/SWIM used inside the machine.

The first (older) version of the IIc does not have what is known as "Mouse Text" in ROM. Mouse text allow ProDOS to have those psuedo windows/folders open on the screen. Thus for ProDOS to have that, it must load them into RAM. This is no big deal in my opinion. the second (newer) version of the IIc and the IIc+ have Mouse Text in ROM. Since ProDOS does not have to load Mouse Text into RAM, so it does speed some things up.

To get 3.5in drives and Mouse Text into an older IIc requires an upgrade of the ROMS and the IWM Chip. Apple used too have this kit but it has been years since I seen on. But that may not be necessary. The Mouse is also different, the IIc uses the older Aple IIe/Mac 128 Mouse, and the IIc+ uses a IIgs/Mac ADB Mouse.

Before I forget, I believe the IIc+ has a faster CPU that you can set into Turbo Mode. I could be mistaken on this but I remember something like this in the IIc+.

For a BASIC Apple II system, the IIc or IIc+ would be the best option.

Another harder to find option is the Laser 128. vTech made an Apple IIc Clone/compatible unit. It's bigger in size and has a built in keypad. But it also has an Apple Slot on the side of the machine to add a card onto it. When I had it, I used a EPROM programmer on it to burn ROMs with it. thing is, the card hang outside ot the unit on the side. It also has the a turbo switch to run the CPU at 1MHZ or 4MHz - which I believe is in the IIc+.

 

Gorgonops

Moderator
Staff member
The older first version of the IIc only uses the 5.25 inch drives; the second newer version of the IIc can use both 5.25 inch and 3.5 inch drives.This is because the IWM/SWIM used inside the machine.
To be clear on something: the only 3.5" disk drive the non-Plus IIc can use is the Unidisk 3.5" Drive, model A2M2053. (Insert standard reference for telling Apple floppy drives apart) And this has nothing to do with the IWM in the machine.

Wikipedia has a pretty good breakdown on the variations you'll find in the original IIc. The short version is there are basically two major motherboard revisions and three major and several minor ROM revisions. The important distinctions are these:

ROM "255": The original motherboard and ROM 16k combination. This one only supports a single 5.25" floppy drive on the external port, and has no internal expansion capabilities.

ROM 0: Same motherboard as above, but the firmware is now 32k. The major functionality change is the disk port now supports "SmartPort" devices so it can drive the Unidisk 3.5" floppy and various SmartPort hard drives.

ROM 3/4: Firmware feature set is basically the same as above, but the motherboard is a new version that has a connector on it for RAM daughtercards.

If you're buying one you'd ideally like to get a ROM 0 or better, but 255s are the most common. A 255 can be upgraded to ROM 0 but the parts to do so might not be that easy to lay your hands on.

When comparing the IIc to the Plus version the major features you get with the Plus are support for the more common IIgs (and Mac) compatible 3.5" drives and a built-in CPU accelerator so it supports running at 4mhz instead of 1mhz. The CPU accelerator is actually in there in part to support the "dumb" 3.5 drives; the disk controller system used by Apple is very CPU intensive and a 1mhz 65C02 is too slow to handle the data rate of the 3.5" drives directly. (The "Unidisk" drive gets around this problem by having its own CPU and buffer circuitry in it.) Just remember, though, that for most IIe/IIc compatible programs the accelerator is by no means necessary, and in fact will do nothing but muck up most games, so there's a good chance you'd be running the machine in the "slow" mode a lot of the time anyway. Therefore I'd hardly call it a killer feature.

Honestly, if all you care about is running classic Apple II software I'd say that a ROM 0 or 3 IIc is probably the better machine. Most IIe/c-compatible software is on 5.25" disks and it's not always trivial to transfer it to 3.5" (especially when we're talking about self-booting stuff, of which there's a lot), so the built-in 3.5" drive of the Plus might be more of a hassle than a blessing.

 
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Elfen

Well-known member
Right on all counts, Gorgonops.

Starting from the ROM 0, as I remember, there is a large Chip on the logic board similar to the Mac LC's Glue chip which is not in the ROM '255.' I believe this is where a lot of the CPU Intensive I/O is done and the 65C02 is left alone. But also, the ROM 0 has that memory expansion slot that the Rom '255' does not have.

Thanks for clearing up the 4MHz part of the IIc+. Oddly, my ROM '255' IIc has a 5MHz Rocket Chip in it, and my Laser 128 (if I can ever find it) has Turbo Mode to 4MHz on a switch above the keyboard.

Looks like we agree on using the older IIc but for different but parallel reasons.

 
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Elfen

Well-known member
Opps! The IIc and IIc+ uses the same mouse that the Apple IIe (with a card) and Mac 128 - Plus used.

I thought the IIc+ used an ADB Mouse, but I am mistaken.

 

Gorgonops

Moderator
Staff member
Starting from the ROM 0, as I remember, there is a large Chip on the logic board similar to the Mac LC's Glue chip which is not in the ROM '255.' I believe this is where a lot of the CPU Intensive I/O is done and the 65C02 is left alone. But also, the ROM 0 has that memory expansion slot that the Rom '255' does not have.
All IIc revisions use essentially the same chipset as the Apple IIe. Here's a photo of a ROM 255/0 motherboard, and here is a ROM 3/4. The locations of a few parts have changed, but the major chips are all the same. Only material differences are: A. later IIc uses denser 4464 RAM so the stock 128k fits in 4 chips instead of 16, B: There's a RAM expansion plug in the lower right corner, and C: The later board has an additional clock crystal, which I believe is related to a serial port fix. There is no magic I/O accelerator chip, "SmartPort" I/O is done entirely in software with the same disk controller hardware as you'd find in the "Liron" controller card for a IIe.

IIc+ motherboards have a big fat ASIC on them; said chip contains the CPU accelerator logic.

 
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senrew

Well-known member
Yeah, I'm just looking for a basic 8-bit setup. I would LOVE a IIe Platinum, but it takes up too much room for the space I have in mind for it.

I think a regular IIc (the later revisions) will do fine. I can connect an external 3.5" drive and still have the internal for 90%+ of the software available. I don't really care about the 4mhz mode on the newer machine since what I intend to program is meant for the normal II speed.

 

Gorgonops

Moderator
Staff member
I can connect an external 3.5" drive and still have the internal for 90%+ of the software available.
Again, just remember the *only* one you can use is the Unidisk model. Depending on how eBay is feeling that week they can go for sort of crazy money. (Budget at least $60 for an untested one.)

 

senrew

Well-known member
That's fine. I don't really have any software on 800k disks anyway, except for the IIgs system disks so I'm good there.

 

FacnyFreddy

Well-known member
FYI: It is possible to upgrade the RAM in the IIc (4000 and 4100) along with a clock board from A2heaven.

I have one in my IIc (4000) and it works fine. I did have to upgrade my ROM to something newer than "0" for it to work correctly, but that was a very minor hack. (some solder glue on one circuit and removing a solder joint on another)

Just wish I could find a zipchip or rocket chip for my IIc... I don't believe there is an "easy" way to overclock the IIc w/o it. (unlike the IIc+)

Ironically, my IIc green monitor died just last week and I am already in the process of 3D printing a IIc monitor stand case for a 12" LCD panel and VGA adapter.

 

senrew

Well-known member
Still haven't acquired a machine yet. Been casually trolling ebay but most of what I find are original ROM machines. Of the newer versions, they are priced way out of what I'd like to spend on an occasional hobby. Still looking though.

 
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