Mike's Hobby Blog

I’ve put a preliminary copy of my ACI build and operations manual online at: http://www.willegal.net/appleii/aci-v0.12.pdf This contains an OCR’d copy (not just a scan) of the original Apple ACI manual, plus a complete assembled listing of the ACI PROM. Take a look and let me know if you see any problems.

Also – remember that this is the last month for discounted ACI presales – get the presale price of $75 through September ’10. Shipments begin late October or early November. Contact me via email at mike@willegal.net if you are interested in the ACI card.

Still working on this one in my spare time. Just completed drawings (not to scale) for the brackets.

Datanetics Keyboard Stiffeners

Layout is coming along also. I have smoothed out the traces on the top and am working on the bottom. Also spent a lot of time working on hole sizes. It is surprising how important this is to a good replica and how long it takes to measure the various holes in a PCB.

Hi,

I have just posted my latest hack. This is a small C program that will convert an Apple Command Line file to AIF format. This AIF format file can easily moved to an iPod and be used to load your Apple 1 through the Apple Cassette Interface.

The program and more information can be found here: http://www.willegal.net/appleii/apple1-software.htm

In case you are wondering, an example Apple command line format file might look like this:

0: A9 00 AA 20 EF FF E8 8A
: 4C 02 00

I just posted pictures of my new PEM (power entry module) on my website.

http://www.willegal.net/appleii/apple1-enclosure.htm

In my opinion, it looks about 100 times better than the crude wood box I was using before. Plus it is smaller and lighter. Judge for yourself.

new power entry module

old power entry module

The Panasonic RQ2102 cassette recorder works about 100 times better than the period Radio Shack recorder that I was attempting to use. I recommend that all Apple 1 owners get one of these while they are still available.  Since it works pretty well, I’m go to go ahead and start the process for making a batch of ACI kits.

First,  I’ll take names for the wait list. Though the layout is done, I don’t want to invest the money until I build up a wait list of around 15 units. Send me an email (my address can found on my website) and I’ll put you on the wait list.  Once the wait list reaches 15 or so units, I’ll ask for money and then order boards and parts.  I expect the cost of the kits to be under $100.

I’ll publicly track the wait list with your initials, date I received your request, and number of kits desired on my ACI page.

Mostly just have schematics which I spent the last week drawing and a few notes on key switches and the encoder part.

http://www.willegal.net/appleii/apple1-datanetics.htm

Current State of Datanetics Layout

I’ve got all connections made, except for the connections from the blank keys to the matrix on the upper left side of the keyboard. From here I may take a break and make a schematic, since I’m not aware of any in existence for this keyboard.

I still have holes to drill and plenty of fine tuning to do. This layout will match a Rev B board. There is a mistake in the original layout of this board which requires a couple of of cuts and and a jumper. I will probably leave the mistake in place.

The pinout of the edge connector is:

Front (from inside of board moving toward edge when facing front of board, left to right)
-12V
B6 (B is data bit)
B5
B4
B1
B2
B3
Reset key pin 1
Reset key pin 2
Output enable (this is an input to the keyboard, but is pulled up on the board to +5 volts)
STROBE (output)
B7
B8
B9
GROUND

back side of keyboard (from edge of board moving inward when facing back of board) (Right to left)
blank keyswitch 2-2
blank keyswitch 2-1
blank keyswitch 1-2
blank keyswitch 1-1
blank keyswitch 3-2
blank keyswitch 3-1
blank keyswitch 4-2
blank keyswitch 4-1
unused
unused
unused
+5 Volts
unused
unused
unused

Now it’s time to go for a bike ride.

Folks,

Quick update – while waiting for the panasonic cassette recorder to arrive, I’ve started work on a new project.

This is going to be a Datanetics Keyboard PCB. This was the keyboard that was most commonly used with Apple 1 computers. There were several revisions made. I’m likely to layout the rev D, since it used most of the same keycap set as early Apple IIs. However, I have access to an actual, original rev B, and may decide that I can do a more faithful replication of that version.

Note that some of the important parts for this keyboard can be very hard to find. The MM5740/AAE keyboard encoder is a very difficult IC to find. Furthermore, the ones you do find, sometimes do not work reliably. Randomly repeating characters after warm up is the symptom of this problem. It would be possible to program a micro controller to accomplish the same function and mount it on a plug in daughter card. However, I think I have enough MM5740′s to satisfy my own needs, so I’ll leave that to someone else. As far as I know, Datanetics key switches and key caps can only be sourced from early Apple II plus computers. The early Apple II/plus keyboards used the same keyswitch and the same style key caps. In fact those keyboards were made for Apple by Datanetics. There are also some metals stiffeners that will be have to be fabricated in order to complete the project.

Because of the difficulty of finding parts, my plans are to only sell bare PCBs, leaving it up to the prospective keyboard builder to find the parts for his build. In addition, I will ask for pre-payment and only order enough PCBs to fill pre-paid orders. I’ll be accepting pre-orders when I feel that the layout is ready for production. The order will be placed when I have enough pre-orders to justify making a build.

I’m still working on the ACI layout, but I have some more things to do.

I want to make sure that I can make operation more reliable before I make a batch of cards for consumption by hobbyists. Besides the capacitor change, I want to find a cassette recorder that works better than the vintage Radio Shack model that I’ve been using. Even with the capacitor change, operation is not the most reliable in the world with this recorder. The recorder I’m waiting to try is the Apple specified cassette tecorder. This is a Panasonic RQ-2102, which much to my surprise is still in production. This recorder was recommended and used by Apple back in the 1970s. I have a new one on order, but it’s on back order and not due to arrive for several more weeks. Used ones are often available on eBay, but I’m looking for a new one, since belts on cassette recorders tend to stretch and slip with age.

The ACI layout is largely complete, with only rounding off of the corners of the traces and final design checks remaining to be done. Though I did the initial layout in a couple of hours, I’ve spent a lot more time than I expected fine tuning the replication of the details of the original. I think that because the board is small, finer fidelity to the original is required to ensure that I capture the right look and feel on this board

Turns out that the Stanford “Apple 1″ is an unpopulated Apple II, rev 0 PCB. The only other unpopulated A2 rev 0 I know of, is the one that the Hudson Brothers just sold. As rare as this is, it would have been nice to find a bare board Apple 1. By the way, during this investigation, an archivist at Stanford Library sent me the best image I’ve ever seen of the front of a bare original Apple II rev 0 PCB. More on that in the next post.