The Brain Board II: Bringing Integer BASIC and Apple 1 emulation to your Apple IIe/II+ with a single card
Background:
The "Brain Board" by Mike Willegal is an Apple II system ROM card, which introcuded machine code known as the "Wozaniam Pack" for an Apple II+ or IIe to emulate an Apple 1, including a working cassette interface for Apple-1 software. This is actually a very appealing way to tinker with Apple 1 audio recordings / programs, because building an actual ACI (and Apple 1 replica or replica-1 Plus) is more difficult and time consuming. The orignial project left room in the EPROM to optionally replace the system ROM, perhaps with integer BASIC. This ROM release is about taking advantage of both of those options with a single card; emulating an Apple 1, and having an integer BASIC card.
The Brain Board II was born of modifications originally done by Macnoyd. He doubled the ROM space on the card, utilizing the unused DIP switch #2 on the DIP bank. The concatenated rom includes 2 copies of the wozaniam pack, and two versions of BASIC (Integer and Applesoft). Depending on the card configuration, the user has the option to replace the Apple II onboard system ROM space with ROM space located on the Brain Board when not using Wozaniam mode. Alternately, in the more common configuration, the system ROM is used when wozaniam mode is disabled. However in that config, DIP2 became irrelevant because both the upper and lower half of the ROM contained wozaniam in both spaces. In other words your options were:
A card which leaves the system ROM usable, but only has Apple-1 emulation mode
A card with Integer and Applesoft BASIC, and Apple-1 emulation mode, but no ability to use the systems original onboard ROM.
To improve the available options, I have released an updated ROM for the Brain Board II, with the focus on making it a true dual purpose card. This allows a user (especially with known good Applesoft BASIC roms / IIe system ROMs in their system) to bring Wozaniam (Apple 1) mode and Integer BASIC to a system with one card, and also always leave the systems own ROM space usable. This is nice if you have a system already nearly full of expansion cards and your ROM version is happy as-is, since previously to have both integer and applesoft BASIC with this card, you had to disable your system ROMs entirely.
Usage:As documented on Github, with a Brain Board II in your posession, burn QuickStart.BIN to a 27c512 or SST27SF512 EPROM/EEPROM. Set the DIPS as follows:
1,3,5,8: ON
4,6,7 OFF
Dip 2: OFF: Boot Wozaniam mode or system roms, depending on rear main toggle.
Dip 2: ON : Boot Integer BASIC mode or system roms, depending on rear main toggle. In short, if you want your brain board to be an integer BASIC card with a toggle switch, set DIP2 of the Brain Board II ON. If you prefer it as an Apple-1 emulation card, leave DIP2 off. Either way, you can reset your system after flipping the rear main toggle to swap between your system rom and the selected Wozaniam or Integer BASIC mode, and pressing CTRL-Open Apple-Reset. To change the card from Integer to Wozaniam, I usually power the system off to switch the DIP2 position.
Default IIe enahanced ROMs running (Rear main toggle of brain board OFF, DIP2: No Use)
Wozaniam Mode / Apple 1 emulation (Rear main toggle ON, DIP2 OFF)
While in Wozaniam mode:
The right arrow key is CLEAR, and be sure you turn on caps lock! The ACI machine code is located at C100 like on a real Apple-1 only if the card is in slot 1 of an Apple II, but you can put the Brain Board II in any slot and subsequently access the Apple 1 ACI machine code at D000 instead. Once you run D000R from Wozmon, usage is the same as in the original ACI manual. As a bonus, unlike a 'real' apple 1, Apple 1 basic is in ROM at E000 already as well.
Full source code, gerbers, and instructions can all be found on my github here: https://github.com/Alex-Kw/Brain-Board-II
Acknowledgements / Thanks:
Mike Willegal for releasing the board design
Bob / "Macnoyd" for his supplementary contributions
User jajan547 on 68kmla for pointing me to the project
Early adopters for their feedback and support
| Attachment | Size |
|---|---|
 QuickStart.BIN | 64 KB |
 Brain-Board-II-main.zip | 1.77 MB |
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