Sunday, June 16, 2024

Completing the Apple IIc Upgrade Experience

The Apple IIc, while a great little system, has a great deal of upgrade potential. In a previous blog entry I talked about the Mockingboard 4c, which is one of the most interesting upgrades for the system, but there are other upgrades worth discussing that may not be worthy of a full blog entry. So here are some of my thoughts and review of some other upgrade options for the original IIc.

Power Supply

The Apple IIc used a non-standard power supply with thick power cables on both ends of a heavy brick. It output 15v DC at 1.2A (18W), was not universal and used a 7-pin Female Circular DIN on the end of the output cable. The external power brick is a linear power supply and contains a fuse but to replace the fuse requires cutting the enclosure and desoldering the fuse. There is an internal switching power supply in a metal box inside the IIc that takes the input from the external brick. The external power supply weighs about three pounds and takes up a bit of space when not in use. If your IIc came without its power supply or you just don't feel like lugging the brick about or replacing a burnt out fuse, bulging cap or dead diode, there are reasonably priced options available. You can certainly find a 12v-15v power supply of the equivalent 18W output and solder on the female DIN connector.


Not many Apple II programs supported the mouse. AppleWorks, Mouse Paint, Apple II Desktop and Dazzle Draw are among the productivity programs which had or eventually acquired support. At least 35 games and educational programs had or acquired support, including Arkanoid, Balance of Power, Dragon Wars, Tass Times in Tonetown and some of the later Carmen Sandiego games. The Apple IIc did not come with a mouse but its joystick port also supported a mouse, unlike the Apple IIe's port which only supported a joystick. The Apple IIc had built in mouse firmware and hardware support which it assigned to slot 4 (see below about slot reassignment). Which mice you can use with this port is a real issue. 

Apple released a fair number of mice in the 1980s. The good news is that we need only concern ourselves with the mice that use the DE-9 connector. Apple introduced the Apple Desktop Bus with the IIgs and ported it to the Macintosh SE, so that limits us to the Lisa, Macintosh 128K, 512K, 512Ke, Plus, IIc, IIc+ and Apple II Mouse Interface Card.

The most common 9-pin mouse is the Macintosh Mouse, model # M0100.  This model came in several cosmetic varieties but feature a single button. Their compatibility with the Apple IIc is hit and miss because the IIc needs to be told that the device which is being plugged into the port is a mouse and not a joystick. The earliest models, which use a beige color with a brown button, are less likely to be compatible than the later platinum gray button models. I have read that M0100s "Made in Japan" are not compatible whereas the ones with "Made in the U.S.A." are compatible. I have also heard that you should look for a less chunky DE-9 connector to maximize your compatibility chances. There is an M0100 with a single color off-white design that is intended for the IIc. It also has a longer DE-9 connector. This would later be given a new model number, A2M4015, with a reversion to a shorter DE-9 connector. It is noted that the ridge of the button is closer to the rear of the mouse than the other M0100s. A later cosmetic update of the Apple Mouse IIc mouse (gray button) is A2M4035. 

The Apple Mouse IIe is A2M2070 and should be compatible with the IIc. This mouse was intended for the Apple II Mouse Interface Card. All M0100s are compatible with the Interface Card. (As a side note, the M0100 is also compatible with the Apple Lisa.)

As the M0100 outputs quadrature signals instead of using a microcontroller, incompatible models can be fixed, either with an external adapter or an internal modification. There are also external adapters which can adapt a PS/2 mouse or a USB mouse to the Apple IIc mouse port. 

Floppy Drive Emulation

The Apple IIc comes with a built-in 5.25" floppy drive and can support a single external 5.25" floppy drive with a 19-pin connector. With ROM 0 or later it can also handle one or two 800KiB 3.5" Unidisk drives and unlike the IIe does not need an expensive Liron card or its modern recreation, the Yellowstone Universal Disk Controller. The IIc cannot use the 3.5" drives intended for the IIgs, those drives do not have the hardware necessary to compensate for the slowness of the Apple IIc's CPU. ROM 0 adds Smartport support, which permits hard drive-like volumes up to 32 MiB in size. If you have a ROM 255 machine upgrading to a ROM 0 or better is easy, inexpensive, reversible and well worth the upgrade. ReactiveMicro can sell you the EPROM you need.

If you do not wish to be limited to magnetic media when using your Apple IIc, I highly recommend buying a Floppy Emu. One huge benefit of the Floppy Emu over its closest competitor, the wDrive, is that it is consistently available. The Floppy Emu is supported in the Apple IIc with the following modes:

Apple II 5.25 Floppy
Apple II Dual 5.25
Smartport Hand Disk
Unidisk 3.5

With the Smartport and Unidisk options, the system will attempt to boot from the internal floppy, and if nothing is found there, it will look to boot a Unidisk or Smartport device. While the Floppy Emu only supports one Unidisk drive, not many Apple II programs came with two 800KiB disks.

You should seriously consider purchasing and installing the Internal/External Drive Switcher for Apple IIc. This allows the Apple II Dual 5.25 mode to work with the IIc, bypassing the internal drive completely. It also allows you to boot from an external drive in either 5.25 mode. The Internal/External Drive Switcher does require you to open your system but does not require soldering. You will run a 2-pin connector from the Internal part of the Drive Switcher out the back of the IIc to the External Drive Switcher. Make sure that the color on pin 1 on the internal part is connected to pin 1 of the external part.

With the switching options shown, set the switches to Normal Mode when you want to use the Floppy Emu's Smartport or Unidisk Modes. The Apple IIc will boot a Smartport or Undisk Drive only after trying the Internal Disk Drive, and it requires a response from the drive even if no disk is inserted. You can also use Normal Mode if you want to use the Floppy Emu as the 2nd 5.25 Floppy Drive and boot off the internal floppy drive. If you wish to use Floppy Emu as the 1st/boot floppy drive and the internal floppy drive as the 2nd drive, then set the switches to Swapped Mode.

It is easier to understand the switching options if you know what is being switched. The floppy disk controller in the Apple IIc has two drive select lines, D0 and D1. The disk drive controller supports two  5.25" disk drives, and the boot drive uses the D0 line. The Apple IIc always tries to boot the internal disk drive and will not boot from an external 5.25" disk drive, which uses the D1 line. Most software will not boot off D1 either. In the Apple IIc, the Internal Drive Connector only has D0 and the External Drive Connector only has D1.

The Internal Part of the Drive Switcher intercepts D0 from the Internal Drive Connector. What gets routed back to the Internal Disk Drive depends on the state of the switches on the External Part of the Drive Switcher. If the D1 arrow points away from the computer, the Internal Drive will get D0 and an External Drive will get D1. If the D1 arrow points toward the computer, then the External Drive will get D0 and the Internal Drive will get D1. This assumes that the other switch has the arrows pointing in opposite directions. If the arrows on the other switch are both facing the same direction and D1 faces away from the computer (so the internal floppy drive does not routed any drive select signal), then both D0 and D1 will go to the Floppy Emu for Apple II Dual 5.25 Mode.

Keyboard Replacement

For the first several years of the Apple IIc's availability, it used a keyboard designed by Apple with their Hairpin Spring switch. Around the time that the Memory Expansion IIc came out, Apple replaced its keyboard with one with Alps switches. If Alps keyswitches are broken or unreliable, replacement switches of similar characteristics can be sourced from a variety of sources. The Alps keyboards are good quality, while I do not own one the Apple Keyboard from my Macintosh SE has similar switches and I do not have a problem with those switches.

The original Apple II keyboard does not have good quality switches, making using the keyboard a chore at best. The switches are custom and their PCB mounting is unique, so they cannot be swapped for better switches. Fortunately in 2024 there is a quality replacement, the Apple IIc Backlit Mechanical Keyboard from MacEffects. It uses quality Matias Click key switches, is backlit with software to adjust the backlight settings and has a metal plate to give the keyboard support. 

The keyboard comes with a choice of gray or clear keycaps. The Caps Lock, 80/40 and Keyboard switches are not latching switches, they use an LED to signify if they are pressed down. The keyboard comes with a metal plate that prevents flex. The keyswitches are tactile and clicky, with the return, control and shift keys being stabilized (and obviously the spacebar). The lettering on the keys is not as well done as Apple's original keycaps, the spacing is just a little "off", to close to the edge, double-function keys spaced too close together, the < and > keys not in alignment height-wise. 

There is power available in the cable that connects the keyboard to its port on the mainboard, so the LEDs comprising the backlight and the controller will work if the cable that goes to the floppy drive is not used. Only basic LED lighting functionality will be supported via the keyswitch combinations. The floppy drive cable is used by the software to communicate with the keyboard's LED controller. This cable poses a bit of a challenge with the Internal/External Drive Switcher, but it is quite possible to close up the Apple IIc with the floppy drive cable installed, as I show in the picture:

Not shown underneath is the Mockingboard 4c, which will sit just underneath the keyboard without issue or potentially shorting out with the exposed pins of the keyswitches.

When these keyboards first shipped to kickstarter backers, it was discovered that the Tilde ~ key was not working on them. While not a huge oversight as the Tilde key was an Apple IIe addition and infrequently used, it still was a ding against the product. They have been selling keyboards on their website post-campaign, so when I heard of the issue I asked MacEffects via their customer support email if the issue was still present and they did not respond. I took a chance and ordered a keyboard anyway. While the issue can be fixed by soldering a wire, I naturally would prefer to get a keyboard with all keys working out of the box. When I got my keyboard I saw a wire soldered to the Tilde key and held down by kapton tape. All the keys worked just fine out of the box, I did not have to "exercise" some keys before they would work like some other recipients reported.

The RGB lighting of this keyboard is very basic. You can turn the backlight on and off (Ctrl + 80/40), adjust the brightness with 10 levels of brightness (Ctrl + Keyboard) or cycle all the keys through five colors (Red, Green, Blue, Violet, White, Ctrl + Caps Lock). You can set the keyboard to cycle through colors from top to bottom (Ctrl + 80/40 on bootup) but it disables Caps Lock and will not stick after a boot. Resetting the keyboard to default settings is done with Ctrl + Caps Lock on boot. Using the backlight will result in a small amount of audible noise when the colors are set to Violet or White. You can set the color of the disk drive activity LED when it is in standby, being read and being written. I could not get the functions on the program to work with my keyboard, maybe because I am usually using an internal/external disk switcher instead of a direct connection from the mainboard to the internal disk drive.

While the MacEffects IIc keyboard is expensive at $225 for the gray keys and $250 for the clear keys, it is an essential upgrade for the Apple IIcs with the original Apple Hairpin spring keyboards. You will enjoy your IIc so much more once you ditch that old piece of crap!

ROM Upgrades

While in my opinion the upgrade from a ROM 255 to a ROM 0 is essential improvement for an original Apple IIc, can the same be said for an upgrade to ROM 3 or ROM 4?  (Really a ROM 4) Those were introduced in the Memory Expansion IIc and while they can be used in a non-Memory Expansion IIc, I originally did not see any significant advantage to doing so. But now I have begun to think differently.

As I stated in my review of the Mockingboard 4c, it's either Mouse or Mockingboard because they both use the firmware memory locations assigned to Slot 4. But the ROM 3 and above relocate the Mouse firmware to Slot 7, which eliminates the conflict between the Mouse and Mockingboard and prevents crashing when soft resetting the machine. I have yet to obtain a mouse for my IIc, so I cannot yet test to the extent the newer firmware affects program compatibility. I do not imagine major compatibility issues because most software scans the slots for the mouse firmware.

But what if you could go further than the stock ROM 4? I resolved to find out by replacing the ROM 0 in my machine (which had previously replaced the ROM 255 it shipped with) with a rom4x. The rom4x is an unofficial modification of the ROM 4 which adds new features. The most important feature is a boot menu which can be invoked by pressing Ctrl + Closed Apple when powering the system on or soft resetting with Ctrl + Closed Apple + Reset. The menu has seven options, 2 & 5 are only useful for a Memory Expansion IIc. But the remainder of the options are useful for original IIc owners. In addition to the options shown, if the system does not detect a bootable device on boot it will automatically go to a BASIC prompt. Typing PR#6 from the BASIC prompt will boot almost any disk.


  1. I don’t have an Apple iic but have enjoyed the floppy emu in my Apple iie enhanced and iigs. I’ve got a physical drive daisy chained for some games that use the second drive for saves. I’ve found it difficult sometimes to get a blank disk to be formatted using the floppy emu for sierra games so that’s why I stuck to physical drives (ie black caukdron my favorite).

    1. Formatting with the Floppy Emu is not guaranteed in my experience unless you use a .woz image for the format. I would also use .woz images for Sierra games as well. I believe all have been dumped in the A Woz A Day archive except for a few I had to contribute.