It’s been a while since I found an Apple 1 program that didn’t run on the Brain Board/Wozanium, but there is a new program out for the Apple 1 that uses the ACI for audio out.

http://www.applefritter.com/content/8k-apple-i-ascii-graphics-lunar-lander-aci-audio-hack-0

Copied here, is my post on the Applefritter forum, describing the fix.

This program will not work as is, with versions Brain Board/Wozanium pack firmware less than version 5.2. There is an issue with the the gosubs 750s in the 900 range (at the end of the program). Those gosubs call directly into the original Cassette interface driver to generate sound. This driver is still present in the Wozanium PROM, but is incompatible with Apple II hardware and will crash the system.

There are several fixes available.

1) remove the call 750s at the end of the program. LInes 900 and 910.

2) Change the pokes in line 999 to call the Wozanium A2 cassette Driver at 0xd0d7:
999 POKE 750,169:POKE 752,32:POKE 753,215:POKE 754,208:POKE 755,96:RETURN

3) If you have a PROM burner, fix the Wozanium cassette driver to work with the A2 hardware by erasing a bit in the PROM – change location 0x01EA in PROM from 0xBC to 0xAC.

4) If you don’t have a PROM burner, send your board or prom back to me and I’ll erase the bit for you.

With fixes 2, 3 or 4 in place, you can attach a preamp to the cassette output of the Apple 2 and get the same sounds as if you were running on an actual Apple 1. It’s kind of funky because the A2 has a built in speaker, which is bypassed, but it works.

If you are running a Wozanium PROM image in an Apple II emulator either:
1) remove the call 750s at the end of the program. Lines 900 and 910.

2) change line 999 to call the Wozanium ACI driver at 0xd1d7:
999 POKE 750,169:POKE 752,32:POKE 753,215:POKE 754,209:POKE 755,96:RETURN

Finally if you don’t have a preamp for the cassette output, there is an inexpensive design on my website that will work for this application.
http://www.willegal.net/preamp/preamp.htm

Marty Ewer is now selling “Retro 1” systems on ebay for $249. They are fully tested Apple IIe computers equiped with my Brain Board. If you are looking for the easiest, least expensive way to an authentic Apple 1 experience, this may be it. In addition, you get a working Apple IIe in the bargain. Search for “Retro 1” under user “shockwavetechnologies” on ebay.

http://www.ebay.com/sch/shockwavetechnologies/m.html?_nkw=%22Retro+1%22&_sacat=0&_odkw=retro+1&_osacat=0&_trksid=p3911.c0.m270.l1313

The Brain Board review in Juiced GS included a description of a bad 74LS244. I have had one other report of problems with the Brain Board in an Apple IIe. In that second case, I had that person send back his board, twice. Though I wasn’t able to reproduce the problem in my Apple IIe with his board, I tried two different repairs, the second of which seems to be successful. The first was a simple swap of the 74LS244, which helped, but didn’t completely eliminate the problem.

After further analysis, I determined that the grounding of the 74LS244 is less than optimal on the Brain Board and switching on of the 74LS244 causes a lot of noise on the ground. Apple boards that use a similar data bus driver circuit (Apple FW card & Super Serial) also exhibit this switching noise. The stock Brain Board is somewhat worse in this regard. I found that adding an additional ground wire on the 74LS244 reduces noise to levels lower than the Apple FW board and appears to solve the problem.

This intermittent operation is typically seen as random characters input while at the console prompt, while not actually typing on the keyboard. If you notice this problem, add a wire between the ground pin of the 74LS244 and the ground lead of the decoupling cap near the other end of the edge connector.

Here is an image of a board with the fix applied.

brainboard 74LS244 ground wire fix

One more word about this problem. Though I didn’t know of any issue with the ground, when laying out the production Brain Board, I considered shortening the ground connection to the 74LS244, running it across the center of the board, instead of the top. This change might have prevented this issue. However, I decided that, since, in several years of operation of the prototype “Brain Board”, I had seen no issues, that it was unnecessary. This is a case where the “if it ain’t broke, don’t fix it” approach, was the wrong approach. For now, the one wire fix will have to do. If I make another run of these boards, the ground trace will be widened and rerouted using the shortened path I considered before.

Also because of this issue, I’m going to have to make major changes to the layout of the protoboard that I have described earlier in this blog.

Peter Neubauer wrote up an excellent review of the Brain Board and it is printed the in September, 2011 edition of Juiced GS.

Check it out – done by one of the folks that picked a kit up up at K-fest.

http://www.ustream.tv/recorded/16320592

Ken Gagne was kind enough to take some Brain Boards out to K-fest and sold them at the vendor fair. Do to these extra K-Fest sales, I’ve now managed to cover my costs in producing the “Brain Board”. Thanks to everyone that has purchased one (or more) of these units.

Because I’ve covered my cost, and it might be interesting to some folks, I’m now releasing the source code for the Wozanium pack.

Also included, is a ROM file suitable for emulators, such as Virtual II. This allows you to run and debug Apple 1 software in the Apple II emulator environment. Just select the .ROM file as the ROM for your machine and reset your virtual machine. Just as in the Brain Board, right arrow will clear the screen. With Virtual II, you can download AIF files of A1 basic and assembly language programs and run them in your emulated Apple II, using the emulated cassette interface built into Virtual II. Note that this ROM version does not include the ACI driver at C100, so you must enter the Cassette driver by entering “D000R”, instead.

You can build the source with the 6502 DASM cross assembler.
Use the following command line:
“dasm a2a1emulv5_1.asm -DBLD4ROMBD=0 -DHUSTNBASIC=0 -oa2a1rbh.o -la2a1rbh.lst”

Included in this zip is

* a1basic-universal.asm – Apple 1 BASIC modified to run on Brainboard/Wozanium (note copyright at beginning of this file)
* COPYING.txt – GNU lincense for rest of Wozanium pack
* a2a1emulv5_1.asm – Wozanium source code
* a2a1emulv5_1.lst – Listing
* a2a1emulv5_1.o – Object file
* a2a1emulv5_1.rom – 12K rom file that can be used with A2 emulators, such as Virtual II.

Click a2a1emulv5_1.zip to download Version 5.1.

More about the Brain Board can be found at:
http://www.willegal.net/appleii/brainboard.htm