osiweb.org

I have been posted about this project in the past but I thought since I have now made a prototype PCB I would post a picture of it. This is my OSI 600 replica named the Superboard ///. It uses a WD65C02 running at 3.3V and 1MHz and a Parallax Propeller micro-controller for the video and ROM section. This is still early in prototype so some things will change. The red color will change and I may add or modify some features. Instead of the cassette port I have the serial port set at 9600,N,8,2 using a USB to serial virtual port FTDI bridge. You can power the Superboard /// right from your computer or from an external USB power supply (not the dinky phone ones).

The video emulates the 25x25 display with the unseen video memory addressable exactly like the OSI 600. A 32x28 mode gives more screen characters and I'm working on how to switch between the 2 modes. The 28 lines is the most that can fit on the video display. 32K onboard RAM gives plenty of memory to go around.

The cassette may or may not be available. I'm working on that but I left it as an add-on board for now. a 3.3V-5V buffer will be required to use original OSI 600 hardware. I also but a cut away section for the BREAK key to hardware an external switch but may change that to a small tactile switch combo with BREAK. This would prevent accidental RESET of the board (been there already).

The keyboard caps were created by me using WASD key caps and Cherry MX switches. The SHIFT LOCK is locking but I only have a few of these. Once these are gone, a standard key switch will be used but a slide switch will handle the SHIFT LOCK functionality.

Let me know what you think so far. I'm trying to do a final prototype by May and get something going by June. I will do a small run of 20 units to start. The size is 11"x8".



Here's my OSI 600 Superboard II that I used to help develop this project:

Looks great Vince. What price are we looking at for the kit?

Phil

The goal is $199 for the kit which is a very difficult task. I may just eat it and do the kits for this price just to make some boards. The expensive part is the keycaps at $60 set and the switches at around $35 set. The PCB is under $20 in quantity and the other parts are minimal. The USB connector that is currently on there will not be in the production version but a similar one will be.

Please put my name down for one! Thanks

/Jeff

I'm down for one as well, regardless if you hit that price goal or not.

Dave

I'm interested as well, but what are the chances of splitting the computer and keyboard into two separate boards? I'd like to be able to use either a real OSI keyboard or perhaps adapting some other keyboard, say Commodore 64.

Steve

It's possible to do that. We've been considering a 2nd version without the keyboard but with a connector port and a PS/2 adapter. Since it is still early enough in the development I'll look into both options. The hard part on the C64 keyboard (or other brand like TI 99/4) would be the matrix would be different and probably not possible. I think the real OSI keyboard matches the matrix of the 600 if I did my homework correctly.

If you made a separate compatible OSI keyboard, they'd be great to use in original equipment as well.

Dave

vbriel wrote:It's possible to do that. We've been considering a 2nd version without the keyboard but with a connector port and a PS/2 adapter. Since it is still early enough in the development I'll look into both options. The hard part on the C64 keyboard (or other brand like TI 99/4) would be the matrix would be different and probably not possible. I think the real OSI keyboard matches the matrix of the 600 if I did my homework correctly.

I have retrofitted a C64 keyboard onto the PET. Just needs a little ROM editing to shuffle the keyboard matrix. Not good for compatibility, but fairly easy.

I heard of people sawing off the keyboard of their Superboard to make it separate. Anyway, PS/2 option would be nice.
I understand the OSI 542 keyboard and the 600 have the same layout but they are actually scanned differently (ie: a key down is "1" on 542 but "0" on the superboard... or perhaps the other way around).

Steve

Steve Gray wrote:

vbriel wrote: I understand the OSI 542 keyboard and the 600 have the same layout but they are actually scanned differently (ie: a key down is "1" on 542 but "0" on the superboard... or perhaps the other way around).

Steve

Yes, the C2/4/8 machines uses inverting buffers, and the 600 uses non-inverting buffers, so although the circuits are similar, the keyboard looks inverted on the C1 relative to the C2/C4/C8.

Dave