Convert Apple IIc to usb


16 Jan 2014, 10:35


i found this forum while searching for a way to use my old apple IIc keyboard with usb.
i found this site ... rectsearch

however since i do not live in the US it is not so easy for me to get this.

is there any other way that people succeded?

thanks for any pointers!

User avatar

16 Jan 2014, 11:43

Hey Braeburn, with a name like that I'm guessing you might be from Scotland too. We do convert a lot of classic keyboards to USB around here. And a Teensy is usually at the heart of the process. The board you've found does indeed use a Teensy++ to carry out its logic. The rest is just plain wiring to a connector:


The good news is that Teensies are available separately, and the IIc converter you've found is open source so you could hook up your own solution. The bad news is that the Teensy++ is quite expensive. £24 from the only UK store that sells it, or $24 plus $10 shipping in the current group buy, which might require ordering a standard Teensy 2 in order to join in. Teensies are fantastically useful things if you're into converting keyboards. I use a bunch of IBM Model Ms and Fs through one, inside this:

The 1960s vintage knob is even older than the keyboards…

User avatar

16 Jan 2014, 12:03

It's using a Teensy++ with the Teensyduino bootloader, plus a board to adapt to the Apple //c connector, and the firmware's on Github (as well as the pinouts). You can do something similar yourself with the appropriate connector and some soldering.

It may be necessary to tweak the firmware for a non-US keyboard. And, it can be tweaked for other boards.

The other option is this project (if you're running Linux), which makes a complete Apple II send keypresses and mouse events over serial to a Linux host:

And, let me guess, you found that you like Alps Taxi Yellows.


16 Jan 2014, 12:10

hey, thanks for all the input so fast!
will do the teensy thing then, but do some oldschool wiring instead of the board.
And, let me guess, you found that you like Alps Taxi Yellows.

User avatar

16 Jan 2014, 12:13

I know almost nothing about Alps myself, and my shelf space says I should probably keep it that way…

Teensies are hand soldering friendly. If you can find the right socket and get all the pinout stuff sorted out, then you're essentially done… hardware-wise. Software can be interesting though. But you'll be able to follow whatever instructions that place made, as you're doing the exact same thing, besides your non-US layout.

User avatar

16 Jan 2014, 12:16

There's two (well, really, three) versions of the Apple //c keyboard.

The first uses Apple Hairpin Spring switches, which are in two words, fucking awful. These can be identified by the rubber splash shield, and the plastic brace on the bottom of the keyboard (although some upgrades required that the brace be replaced with a carbon fiber brace to reduce height).

The second uses Alps SKCM taxi yellow switches, which are my favorite switch. This can be identified by the plate that the Alps switches are mounted to.

The third is the IIc Plus keyboard, which uses Alps SKCM orange switches, although I think it's not compatible with this firmware and has a different pinout. The IIc Plus was only ever sold in the US (so no ISO variant ever existed), and its keyboard can be identified by the volume control on the keyboard (pre-Plus machines had it on the motherboard) and the L-shaped enter key (pre-Plus ANSI //c keyboards used a straight Enter key).


16 Jan 2014, 17:49

Sadly, both of mine are the "Apple Hairpin Spring" ones, so I'd never even consider converting them to USB.


16 Jan 2014, 17:55

Muirium wrote:Teensies are fantastically useful things if you're into converting keyboards. I use a bunch of IBM Model Ms and Fs through one, inside this:

The 1960s vintage knob is even older than the keyboards…
I like that. You need some kind of vintage indicator background to make it work though... maybe something from an old medical device, with one indicator saying "Gamma" and the other saying "X-ray". (Then you can tell people you once accidentally increased the gamma - you're OK as long as nobody makes you angry.)

User avatar

16 Jan 2014, 18:36

There's actually a third input on the far side. In total it does everything Soarer's Converter can accept: XT/AT, PS/2 and RJ45. Good job, as I use all of them.

I have a sweet on/off switch with vintage background, but there's not enough room inside that box as the rotary switch is just as vintage as the knob on top and is therefore freaking huge. Only just fits inside! The Teesny is stuck up in the corner above the USB output socket.


19 Jan 2014, 22:14

ok, thanks for the replies,
i will try to rebuild the github project ( albeit not with an etched board, but with a rasterboard).

tweaking the firmware to deal with the german keyboard layout might be a little tricky ...

any help and suggestions greatly appreciated!

User avatar
Daniel Beardsmore

20 Jan 2014, 23:19

bhtooefr wrote:The second uses Alps SKCM taxi yellow switches, which are my favorite switch. This can be identified by the plate that the Alps switches are mounted to.
Is there a reference anywhere to the production years for the IIc variants? I'm trying to track down the production years of the taxi yellow Alps and also determine whether it came before, at the same time as, or after blue Alps.

I didn't realise that the click leaf in taxi yellow Alps switches was different to other clicky Alps switches.

User avatar

21 Jan 2014, 03:41

Apple Hairpin Spring switches were used from April 1984 to August 1986 (in //cs with model number A2S4000, ROM revisions 255 and 0 (although newer ROMs can go in those)).

Alps SKCM taxi yellow switches were used from September 1986 to August 1988 (in //cs with model number A2S4100, ROM revisions 3 and 4).

Alps SKCM orange switches were used from (on the IIc line anyway, Apple certainly used them elsewhere, dating as far back to the IIGS in September 1986) September 1988 to September 1990, on the IIc Plus, model A2S4500, ROM revision 5.

Sources: and although the comments on keyswitches are from memory. (The switch to the Alps keyboard was required by the Memory Expansion system, which needed a plate mount switch to get the keyboard rigidity without compromising on clearance to the motherboard.)


21 Jan 2014, 08:55

Thanks, bhtooefr. That is very useful information and should make it easy to find one with yellow ALPS.

The link was interesting too. I had no idea that Jobs wasn't part of the Lisa team.

User avatar

21 Jan 2014, 15:08

He got kicked off the Lisa early on. I need to look it up, but after the trip to Xerox Parc which changed everything. That's how he wound up throwing Jef Raskin out of the Mac project and taking it over completely. The Lisa remained the big ticket make-or-break Plan A, which gave Steve and his cheeky pirates in the Mac group all the latitude they wanted to take risks and cut corners. The two teams clashed routinely as the Mac became more like the Lisa. But the key developer behind both projects, Bill Atkinson, was too vital to the Lisa guys to lose, so they had to cooperate.

Ultimately, the Lisa cost too much and (just as importantly but often overlooked) shipped with a complete office suite built in which kept 3rd party developers away, waiting to see who else bought it. Meanwhile, the Mac launched a year later, stole all the thunder, and that was that.


21 Jan 2014, 18:00

(Warning... going far off original topic... warning... emergency... flashing lights... beep beep...)

It's amazing how many people out there believe that Apple "invented the GUI" with Macintosh. Many others say the GUI was first on the Lisa. Some people know the history well enough to mention that there was one GUI before Apple, on the Xerox Alto - but it was non-commercial prototype, so Apple was still first to sell. Almost nobody mentions the Xerox Star, a commercial product released 2 years before the Lisa came out:

There are at least 2 other products advertised with GUI interfaces in BYTE magazine issues, along with entire articles on GUI concepts before the Lisa was released.

User avatar
Daniel Beardsmore

21 Jan 2014, 23:05

bhtooefr wrote:Alps SKCM taxi yellow switches were used from September 1986 to August 1988 (in //cs with model number A2S4100, ROM revisions 3 and 4).
Thanks — I was fearing that it would have been too late to have been a clear precursor to blue Alps.
mr_a500 wrote:Almost nobody mentions the Xerox Star, a commercial product released 2 years before the Lisa came out…
I am glad Apple introduced drag and drop :) And people say that ejecting by dragging to the Trash was bad — but Star has you move documents to the printer?! The video clearly shows the file disappearing when you begin the move operation to "move" it to a printer, which is absolutely terrible UI. Nothing should just vanish, and you "copy" to a printer, not move!

Still, it was really nice to finally see Star in action — even screenshots of it are pretty rare. It's horrendously slow though, and that in part went against it. It was a lot of money for something with lag.

Personally I consider it even the Lisa and Macintosh to be dubious — how much harm did Apple do to the industry by allowing people to afford a small piece of something completely unobtainable throughout the 1980s? It's a very tough call, as you need a market to drive the innovation of something that no-one should have until it's perfected.

At least Apple tried — I have no idea WTF IBM were trying to do, or Microsoft. DOS was always utter garbage and the IBM PS/2 never took the leap that the Macintosh II did. I hold the IBM PC more responsible for the festering pit of filth that is the IT industry than Apple.


23 Jan 2014, 00:56

hello clickers!

i managed to build the adapter board and connected my german IIc keyboard to it.
arduino compiled with no problems.
keyboard gets recognized and tracks the umlauts and other special characters without a problem.
however the bottom row of keys between the shift keys ( "y" to "-" on german keyboard ) dont get recognized.

need to figure out if this is a software or hardware ( in the adapter ) problem...
any ideas how to start?


User avatar

23 Jan 2014, 08:37

That entire row?

Converters tend to either work perfectly or not at all. I'd expect a few mismapped keys (as I get on my huge 122 key Model M before fixing with a remap) rather than a huge dead zone. A broken row is the sort of thing to expect from a broken keyboard instead.

Have you used this keyboard with the original Apple IIc hardware?


23 Jan 2014, 10:17

yes, it works perfectly with the machine.
tested another IIc keyboard as well.
ah, found the culprit ... one faulty solderpoint....
Last edited by Braeburn on 23 Jan 2014, 11:22, edited 1 time in total.

User avatar

23 Jan 2014, 11:21

I would follow the traces if you can, to see if you can figure out where those keys are going. They may well have added another row that they didn't use on the US keyboard, for the one missing key, or something strange like that. (That may also have been how they handled national layouts, using different rows to use the same encoder.)


31 Jan 2014, 05:37

Hi all.

I sell the RetroConnector products that the OP mentioned.

Glad to see you got your conversion working. Let me know if you need any assistance modifying the Teensy code for your keyboard layout. I presume it's AZERTY?



31 Jan 2014, 15:19

Would you be interested in selling a few of these, or at least in providing a schematic for the wiring to the Teensy++?

I have been wanting to convert a few //e KBs to use in my XServe rack.:)

I presume this would work for the //e+ (//e with numeric keypad) version as well as the //e and //c... What about the II+? I recall it had a slightly different interface (as well as lacking many keys). The Original //e KB would be ideal for a 1U KB drawer. :D

How much do you know about the Lisa KB, with that phono jack (and the later Mac 128-through Mac Plus KBs with the RJ12 connector)? I have often wanted to convert one of my old Lisa KBs into something that I can use on a modern system, as that would be brilliant, as would using a Mac+ KB. Both have a full numpad, and would be nice to use. I wish I had one of those Bell Labs black versions,as they were so clever and posh.

If you are interested in selling any adapters,please contact me. Otherwise, a schematic would be fantastic;as would anything to use Lisa and pre-ADB Mac KBs on new HW.

(I make mainly video conversion stuff, but I can handle my way through a diagram. If I looked closely at a data sheet for the Teensy, I could figure it out, but if you have already done the work, and in a very professional manner, if I may so so, why re-invent the wheel?)

(Edited to enable notification.)

User avatar

31 Jan 2014, 15:35

The Teensy is a reprogrammable microcontroller. It's pretty powerful, within its limitations. Understanding it by looking at a data sheet would be like doing the same for any microprocessor. Everything depends on the code its running.

As for the Mac Plus keyboard: here's a project with the appropriate code to make a converter for it, the original Mac keyboard (which I just recently acquired) and plenty more besides: ... t4478.html

@option8: is the Apple IIc keyboard's matrix really so big it needs a Teensy++ instead of a regular Teensy 2? There's a significant price difference.


31 Jan 2014, 15:57

@Muirium Yep. The //c is a 10x8 matrix, which, barring using a multiplexer, means at least 18 pins. Then there's the non-matrix keys - CTL, SHIFT, CAPS, etc - each requiring their own input. I also liked the idea of being able to hook up the other LEDs in future versions, and leaving some room for extra features.

@TheDoctor I sell adapters and kits for the IIc and IIe: ... apple-iie/ ... apple-iic/

And yes, the IIe version works with or without the numeric keypad.

The II and II+ use an ASCII keyboard instead of a matrix, but there are projects online to convert those as well. The downside is there's some hoops to jump through to get lower case text and modifier keys.

Schematics and all my code are on github:
If you're up for building your own, here's the pinouts I used for the //c version:

Code: Select all

Keyboard matrix

     X0    1    2    3    4    5    6    7    8    9
Y0  ESC    1    2    3    4    6    5    7    8    9

1   TAB    Q    W    E    R    Y    T    U    I    O

2     A    D    S    H    F    G    J    K    ;    L

3     Z    X    C    V    B    N    M    <    >    ?

4                                   \    +    0    -

5                                   ~    P    [    ]

6                                   RET  UP   SPC  "

7                                   DEL  DN   LT   RT

    J9  Teensy

X0   31    26
1    24      4
2    22      5
3    8       14
4    14      17
5    6       13
6    10      15
7    1       3
8    4       12
9    2       11

Y0   12      16
1    33      25
2    18      7
3    20      38
4    3       2
5    5       1
6    7       0
7    9       27

NC   13

GND  21      

SFT  34      24
CTL  32      23
CMD  16      43    
CMD  26      44
CAPS 28      21

J9 pinout
1    X7
2    X9
3    Y4
4    X8
5    Y5
6    X5
7    Y6
8    X3
9    Y7
10    X6
11        DISK LED (5v)
12    Y0
13        NC
14    X4
15        KEYBOARD SW
17        NC
18    Y2
19        40/80 COL SWITCH
20    Y3
21        GROUND ???
22    X2
23        5V ???
24    X1
25    POWER LED (5v)
27        LED GROUND ???
29        RESET
30        NC
31    X0
33    Y1
34    SHIFT

Share and enjoy!



31 Jan 2014, 16:26

A brief question:

You have firwmare to flash, and I want to know if this is mandatory,or if the kit is pre-flashed with the option to re-flash it later.

Not a problem either way, but an out of the box product would speed up usability.

Do you have any comments about Lisa and Mac 128K/Mac Plus KBs? I've wanted to use a Lisa KB on a new system for ages, and I can probably dig up specs and schematics for it if needed, or just post one to you at some point.

User avatar

31 Jan 2014, 16:28

Teensies flash via USB, as simply as can be. As many times as you like. It's essentially drag and drop once you install the app:


31 Jan 2014, 16:31

my RetroConnector Shields come flashed with the latest version of my firmware, and can easily be updated via USB.

I haven't built anything for the 128/512/Plus keyboard yet. I'm working my way up to those and ADB.

User avatar

31 Jan 2014, 16:49

Although, you can remove the encoder from an original Apple II or II+ keyboard and then get at the matrix that way...


31 Jan 2014, 17:06

Ah, well, if you ever find any interest in making a Lisa transceiver, I would be pleased to help. The RJ11 Mac stuff has some support in this area, albeit nothing to use out of the box, but the Lisa has naught, and Lisa KBs without systems are plentiful.

I'm curious why you didn't pre-flash the modules, given their specific nature, to appeal to the less technically inclined. That said, flashing it should be easy-peasy, as long as that host runs on a system I own (XP, Linux, OSX).


31 Jan 2014, 17:36

@TheDoctor - I _do_ preflash the modules. I wouldn't assume customers want to install the Arduino IDE, go through the trouble of also getting the TeensyDuino library, as well as the keyboard/keypad libraries.

If you want to send me a Lisa keyboard to experiment with, I'll be glad to get cracking on that. You're the first person that's expressed an interest in the Lisa keyboard to me.

Post Reply

Return to “Keyboards”