Updated "Brain Board" for Apple II, originally designed by Mike Willegal
Go to file
2023-10-31 16:23:22 -04:00
27c512 mod original docs Delete .DS_Store 2023-02-08 17:50:55 -05:00
Forum Pack renaming files for consistency 2023-10-31 16:23:22 -04:00
Source and Serial Driver Delete .DS_Store 2023-02-08 17:51:21 -05:00
bb-v5_1.pdf initial file upload 2023-02-08 17:47:18 -05:00
brainboard.htm initial file upload 2023-02-08 17:47:18 -05:00
LICENSE Initial commit 2023-02-08 17:24:36 -05:00
README.md Update README.md 2023-10-31 15:32:05 -04:00

Brain Board ][

Updated "Brain Board" originally designed by Mike Willegal

s-l500

The Brain Board II is a slot card for the Apple II, II+, and IIe computers. It allows use of the Wozaniam pack to mimic Apple-1 Operation (including Cassette interface), as well as provides a user ROM area which can be used to boot Integer BASIC among other possibilities.

The original documentation for the card can be found on Mike Willegal's site: http://www.willegal.net/appleii/brainboard.htm

The BOM on page BB:3 should be appended from the original design as follows (This information is reflected in the PARTS LIST section below):

Include one more 10K resistor. (5 in total)

The 6 non-polarized capacitors shown on this page should be .1uf, not .01uf.

Lastly, it is imperative to use a 27C512 or SST 27SF512 with this design in place of the 27c256 EPROM.

Normal operation is the same if you follow the quick start guide from the original Brain Board manual. bb-v5_1.pdf is provided in this repository, but for convenience, these are the 2 most common settings.

SETTING 1: QUICK START

DIPS: 1,3,5,8: ON

4,6,7 OFF

DIP2 doesn't matter, the wozaniam pack is in the same relative location in both banks that this DIP controls (in the standard/provided Integer + Applesoft ROM in this repo)

In this mode, the back toggle will switch between normal system ROM, and the Wozaniam (apple 1 emulation) mode.

The updated design to take advantage of this Brain Board II modification / DIP2 uses the following configuration:

SETTING 2: APPLESOFT / INTEGER BASIC

1,4,5,7 ON

3,6,8 OFF

2 - Toggle Between FP/INTEGER BASIC (Apple II)

In this mode, the back toggle will still enable Wozaniam when up, but when flipped down, it will boot either Applesoft or Integer BASIC from the Brainboard's ROM depending on the position of DIP2. DIP2 was unused in the original Brainboard design/documentation. If you do not need Apple II Integer basic, the first config is most compatible with other expansion cards and accessories. The second config makes the brain board more versatile but may cause conflict with some expansion cards.

In this mode, the system ROMS are entirely on the Brain Board (this is done by inverting switches 3/4 from the previous settings). This means that you should be able to run a board with no onboard ROMs in theory.

GETTING A CARD:

Sometimes I have completed cards on my eBay store, and bare PCB's are always available there: https://www.ebay.com/str/arcadealex

I can also be contacted via AppleFritter Forums or VCF for a DIY kit, username skate323k137.

MAKING IT YOURSELF (Without a kit and/or PCB from me):

The 'Forum Pack' directory has everything you need to get a card manufactured, and to program your ROM presuming you have an EPROM programmer. A TL-866 or TOP-3000 etc is sufficient. Within that directory you will find:

Beta_4_gerbers.zip - Can be uploaded directy to PCBWAY to get your own PCBs fabricated. Use their option to bevel the edge connectors, and if they ask you if they can trim a little length from the edge fingers that is fine. Alternately I have uploaded the project to their site, and I receive a small commission if you want to purchase unpopulated PCB's via this link: https://www.pcbway.com/project/shareproject/Brain_Board_][_For_Apple_II_computers_d632392b.html

BrainBoard_512_Beta_4.zip - Osmond Project (Free PCB editor software), can be opened in the program OSMOND and modified. Delete AUX2 layer after you export Gerbers, AUX1 is board outline.

CO.512.SuperBrain_Board AppleSoftInteger.BIN - Burn to a 27C512 or SST 27SF512 ROM. Contains the ROM necessary for both of the above configurations (SETTING 1, SETTING 2).

Other files found in this repository are copies of Mikes original code/design to keep it together under GPL, and the original photos/documentation of the ROM mod by Macnoyd from which this hardware revision was derived.

PARTS LIST

Parts List