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Reviving Mike Willegal's 'Brain Board' For Apple II computers

Skate323k137

Well-known member
Recently @jajan547 posted in another thread about Mike Willegal's "Brain Board" for Apple II computers. The two of us decided it would be worthwhile to split a JLCPCB order. Mike abandoned this project years ago, but in doing so, he also generously made the files and source public.


This board allows an Apple II / II+ / IIe to act like an Apple 1, including cassette driver.

The first hurdle was that the gerber files didn't want to process right on modern manufacturers. Ultimately here is how I fixed the files from Mikes site:

-Downloaded Osmond (Free PCB making software)
-Opened the osmond file from Mike's site, and then set the project dimensions/grid to mm in the menu (likely optional)
-Before exporting the gerbers, you have to use the menu to edit the filenames. The main thing is setting the right file extension for each layer, as Osmond has the same by default. This guide has a table at the top which should work: https://support.jlcpcb.com/article/29-suggested-naming-patterns
-Unfortunately there is some trace text outside the footprint of the entire PCB I cannot locate in osmond. This causes problems at JLCPCB but not PCBWAY.
-Exported the gerber files with aux 1 as board outline, deleting aux 2 layer file entirely.

Once that was all set, we ordered some from PCBWay.

jODoKyD.jpg


I received these this last Saturday and built 2 units; one with a switch on the card, one with pin headers for a remote switch. Apple II+ slots can allow access to a soldered on switch, but systems like IIe the switch is very tight against the back of the system and I recommend pin headers and a remote switch. Take 5 right angle headers (normal pin headers like for hdd jumpers, but right angle), extract pins 2 and 4, and then solder it in. See photos. I used a sideways jumper to hold the pins parallel to the PCB while soldering on the header.

98FjX1V.jpg


FWiGkii.jpg


5m2eDcl.jpg


dfpADce.jpg


I tested using a couple pieces of Apple 1 software; I keep an iPod full of Apple 1 software handy for my Replica 1 plus which has a cassette interface. Overall the thing works as expected. Even in my IIe systems with tons of expansions, the only conflict I had was with this in slot 5, trying to boot CP/M from floppy in slot 6 (that CP/M card itself is in slot 3), when it initialized drivers it dropped me to an Apple 1 startup. I wager if I can get it into slot 1 it may fix this, but I would have to shave my uthernet connector that is in the way.

Fe6ZkOt.jpg


DCTWSvI.jpg


At this point I am modifying the PCB design to use a 27c512, as there was one unused dip (#2), and another person had done this modification in practice just not to the fabricated PCB design: https://www.applefritter.com/comment/83113#comment-83113

I've revised it in Osmond; once Macnoyd has a chance to double check it, I'll probably order some new/revised "Brain Board ][" PCBs intended for the larger ROM.

Here's a little video of the ASCII art displaying from the Apple 30th Anniversary program.


Thanks to @jajan547 for inspiring the revival of this project and macnoyd on AppleFritter for providing his concatenated ROM file and details of the physical bank switch to save us some time.

Attached to this post for convenience of anyone else is an updated copy of the Gerbers which worked fine at PCBWAY. Again, JLCPCB gets the wrong dimensions due to an issue I cannot find/fix in Osmond (text far outside the PCB outline) which does not impact PCBWAY. Also PCBWay has an option to bevel the PCB edge connector; this worked as well.
 

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jajan547

Well-known member
This is such an awesome project and undertaking, my board arrived today and I’ll be putting mine together later today. I’m excited to try out all of its features and learn more about it. Thanks for sharing with everyone and splitting a PCB order with me @Skate323k137 :).
 

Skate323k137

Well-known member
I hope you enjoy assembling your kit, this is a pretty quick portal to the mid 70s computing experience. The Apple Cassette Interface manual will be your friend, if this card is in slot 1 you can just follow it verbatim, if it's in another slot just invoke the ACI at D000 instead of C100.
 

retr01

Active member
Hmmm, I like the power switch. That means turning it off, and the IIGS can use the slot for whatever other resources I need the slot for. :unsure:
 

retr01

Active member
I may need to put the switch in front since it would be hard to get behind the IIGS in my set up.
 

Skate323k137

Well-known member
I actually do not think this card works in a IIgs. It definitely works in II / II plus / IIe systems, but I have not seen anywhere someone trying this in a IIgs. Also since the IIgs is lacking a cassette interface you would be missing that as well.

The Apple 1 and II are more similar than the II and IIgs are, I don't know how the IIgs processor or memory would respond to this card, and actually would not encourage anyone to try it unless they have extensive knowledge of the Bus on the IIgs to know it's no risk.
 

retr01

Active member
Hmmm. :sneaky:💭

:oops: <-- @Skate323k137
:D <-- @jajan547

Aha! 🤓☝️

The Apple ][, ][+, and earlier //e used the MOS 6502 CPU. The IIGS was set up to have 8-bit and 16-bit modes. 8-bit programs for the Apple ][, ][+, and earlier //e could be run on the Apple IIGS that the 65C02 could process programs written for the 6502.

So, the Apple I used MOS 6502 that Steve Woziank selected and engineered the archiecture of the Apple I system. Since the IIGS can run 6502 programs, it should be able to run Apple I programs.

However, the Apple II series did not have certain ICs that seperated the Apple I from the Apple II series. So, this card enabled the Apple II series to run Apple I programs with the necessary ICs. As for the IIGS, if the IIGS can use most cards for the Apple II series, such as Z80 card to run CP/M, why not see if this card will work? :) Ah, yes, the issue is that the IIGS does not have a cassette interface.

Wait a minute! There is hope! *Star Wars music playing from Star Wars IV: A New Hope* Take a look at this comment:

Reproduce the cassette input on a circuit card using a 741 op amp, a capacitor, and a couple of resistors. Wire the 741 output to the game port (pin 9?) to get the bit to C060, and you are ready to go. Oh, you'll have to use the monitor to input the cassette read code into RAM, and then jump to it.

The GAME PORT on the Apple IIGS! What do you think @Skate323k137 and @jajan547??!! I have a thread going on about the game port over at TinkerDifferent and a lot of things that could be used on the Apple IIGS via the game port. I do not think many in the Apple II community realize about this. The Apple IIGS actually has the game port to expand it to other things that were created back in the late 1970s and early 1980s. :)
 

Skate323k137

Well-known member
I really really like where your head is at, I'll say that :D

My IIgs is a bit of a prized possession, I'm the 3rd owner and retain all original receipts, accessories, and documentation. So I just didn't want to be the 1st to put this card in and hope :'D. Like, I don't think anything will explode, I just would want to do more reading and such before popping it in.

Tell you what, @retr01, the photoed one in the platinum IIe is my 2nd unit, my 1st is in my II+. If you really are willing to test/try it in an IIGS and document the result, I could probably be talked out of it, or I would also be willing to offer you a kit at a low cost (more info on kit availability potentially in coming days for other folks). But if you don't have another Apple II I would hate to take any money from you for something you might not be able to get working unless you're 100% in for that situation.
 

jajan547

Well-known member
I really really like where your head is at, I'll say that :D

My IIgs is a bit of a prized possession, I'm the 3rd owner and retain all original receipts, accessories, and documentation. So I just didn't want to be the 1st to put this card in and hope :'D. Like, I don't think anything will explode, I just would want to do more reading and such before popping it in.

Tell you what, @retr01, the photoed one in the platinum IIe is my 2nd unit, my 1st is in my II+. If you really are willing to test/try it in an IIGS and document the result, I could probably be talked out of it, or I would also be willing to offer you a kit at a low cost (more info on kit availability potentially in coming days for other folks). But if you don't have another Apple II I would hate to take any money from you for something you might not be able to get working unless you're 100% in for that situation.
I wouldn’t try it unless you are willing to potentially damage something. I agree the enthusiasm and research is great but the consequences could be deadly it’s best to try on a beat iigs or a rough one. That being said like @Skate323k137 said more information on kits in the comings days. These are pretty straightforward to assemble. And they are really cool to use, do you have another Apple ii series system you can use? I’ll try and find some diagrams as to what can be done but if you don’t have the Casette interface it kind of limits the amount of fun you can have with the apple I, this was used to load programs, games, and files and without it your essentially left with straight apple i code.
 

retr01

Active member
I wouldn’t try it unless you are willing to potentially damage something. I agree the enthusiasm and research is great but the consequences could be deadly it’s best to try on a beat iigs or a rough one. That being said like @Skate323k137 said more information on kits in the comings days. These are pretty straightforward to assemble. And they are really cool to use, do you have another Apple ii series system you can use? I’ll try and find some diagrams as to what can be done but if you don’t have the Casette interface it kind of limits the amount of fun you can have with the apple I, this was used to load programs, games, and files and without it your essentially left with straight apple i code.

The Apple IIGS has a game port. It can have many, many things hooked up to it. A small cassette interface board can be hooked up to the game port. That would need to be done, which I think will be relatively cheap. See my post above that included the components needed to build that:
  • a circuit card
  • 741 op amp
  • capacitor
  • a couple of resistors
  • connect 741 output to the game port (pin 9?) to get the bit to C060
I think this concept could work. The hardware in the IIGS should pick up the audio from the external cassette player through the game port as it is directed to the C060.

This book here should cover the right voltages interfacing to the game port:

1664294437254.png

The risk would be minimal if it interfaced correctly to the game port on any Apple II computer. Down the road, it can be used to play music or other audio on the Apple II series. If you or @Skate323k137 could build that small board and ship it to me, I can test it on my IIGS. I'd be happy to order the parts and have them shipped to one of you.
 

retr01

Active member
I really really like where your head is at, I'll say that :D

My IIgs is a bit of a prized possession, I'm the 3rd owner and retain all original receipts, accessories, and documentation. So I just didn't want to be the 1st to put this card in and hope :'D. Like, I don't think anything will explode, I just would want to do more reading and such before popping it in.

Tell you what, @retr01, the photoed one in the platinum IIe is my 2nd unit, my 1st is in my II+. If you really are willing to test/try it in an IIGS and document the result, I could probably be talked out of it, or I would also be willing to offer you a kit at a low cost (more info on kit availability potentially in coming days for other folks). But if you don't have another Apple II I would hate to take any money from you for something you might not be able to get working unless you're 100% in for that situation.

I would love to try it on my IIGS, but I still need a cassette interface. So, as a workaround, can IIGS owners have the audio files converted to a floppy disk or image, as there are ways to do that already? I'd be happy to test that way.

I suggest moving forward with this project to ensure people are interested and then looking into adding the cassette interface for the Apple II series game port, including the IIGS, right after. :)
 

Skate323k137

Well-known member
@retr01 Here is my current roadmap:

My first interests are:

1.Finish a beta build and hopefully have a working 2nd bank (Hardware switch) based on Macnoyd's 27C512 ROM image.
\_If this works I will be making info (gerber files, source code, documentation/notes) available both excitedly and dutifully under GPL.

2. Start learning where to place code In the banks, so maybe we can get KRUSADER or some other Apple1 program in ROM in place of AppleSoft in one of the banks.

This will open up some possibilities for people to get more creative I hope.

Dream/Future goals:

-Figure out EPROM structure/correlate to machine code listing of wozanium pack.
-Understand the super serial driver which is already in the wozanium pack / monitor listing, and establish a serial connection of any sort
-Figure out if there is possibility for memory mapping for larger programs like P-LABs Hangman
-Maybe a look at IIgs is possible for me, if someone has not beaten me to it. I feel like it would be mentioned on Mike's site if it worked; you could always email him.

In doing this I'm sure I'll learn more along the way. The PDF documentation for the Brain Board is very thorough. Finding ways to interact with the Game port from Apple 1 is beyond my current scope of knowledge but that book on interfacing with the II+ looks fantastic. I always have the urge with anything pre-macintosh era to buy physical books on the subject. I know on the II+ the game port is often used for a wire for a shift key modification.

Anyway, disk images; no such thing for Apple 1 I'm afraid. Cassette was what you had. If you buy a replica-1 kit or build a replica Apple 1, you'll find software just in audio or text form, and language wise you will find just machine code or Integer basic programs. At one point I think Uncle Bernie of AppleFritter acclaim was working on a Disk operating system for actual Apple 1, but he is retired and he himself would tell you 'who knows' when he would get back to that.

This would lead me to another dream goal of something like the P-LAB SD card for Apple-1 (which is awesome) working in conjunction with this, but there is considerable work in anything like that. The P-LAB card actually has a functional command line interface and file system, on an actual Apple-1/clone (and now, Briel Replica 1 Plus!). I have a video of a bank switch modification I made to the Briel replica 1 ROM; in an additional bank I modified the woz monitor which runs on reset to jump to the SD OS after initializing the PIA. This video should give people a relatively good idea what using a replica 1 is like, and also show the huge convenience provided by the P-LAB card.

 

retr01

Active member
Maybe a look at IIgs is possible for me, if someone has not beaten me to it. I feel like it would be mentioned on Mike's site if it worked; you could always email him.

Okay, I will try contacting Mike.

Finding ways to interact with the Game port from Apple 1 is beyond my current scope of knowledge but that book on interfacing with the II+ looks fantastic. I always have the urge with anything pre-macintosh era to buy physical books on the subject. I know on the II+ the game port is often used for a wire for a shift key modification.

A lot of interfacing can be done via the game port. I can contact some folks and get more information.

Anyway, disk images; no such thing for Apple 1 I'm afraid. Cassette was what you had. If you buy a replica-1 kit or build a replica Apple 1, you'll find software just in audio or text form

Yes. The Apple I "disk images" are either text or audio. I believe the latter is more widespread because it was easy to use the cassette tape with the low/high pitch sounds to indicate the binary 0 and 1. Volume should be taken care of since too low or high volume will mess up the data stream via audio.

The way to convert audio to a data file (text) is pretty straightforward. Vice versa, some programs can do that. For example:


Or, download an archive of seven 800 KB disks of the programs extracted from the cassettes from Brutal Deluxe. :)

language wise you will find just machine code or Integer basic programs.

That is correct; just machine code or integer basic.
 
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