OSI 600 Superboard II replica

[vbriel]

The project page is up and final stages are underway for production. The first run will be limited to 20 units. The kit price will be $199 thanks to WASD working out a better price to make this happen. The final prototype is up for viewing and the color of the board will be blue. I chose blue because it matched the USB controller I'm using and some models of the OSI cases were blue. You can visit the project page here:

http://www.brielcomputers.com/wordpress/?cat=39

Kits will go on sale this month. I'm not going to offer assembled until after July.

Here's a small picture of the final prototype:

[Jeff]

I want one so bad, I can taste it!!!

I am currently working on dissembling the SYN600 ROM and noticed that, on the C4P, anyways, storing anything other than $00 in memory location $FB (zero page) transfers input from the keyboard to the ACIA at $FC00. Clearing $FB back to zero restores native keyboard response. This is how it works in the Monitor anyway, not sure of Basic.

[MK14HAK]

Vince what limits this video to 32 x 28 ? Too narrow for my liking.

[dave]

Vince, this looks fantastic. I look forward to this release.

Dave

[scowl]

Vince what limits this video to 32 x 28 ? Too narrow for my liking.

Yeah, I spent a week soldering piggy backed chips for the 32x64 video mod on my 600. I don't want to do that again!

[vbriel]

The issue I'm having is the 64 width is good on the display but the memory map doesn't like 64 across. What happens is the display puts a line of text half way across the screen, then the next line is at the left margin. As the page scrolls, it shifts the data in 32 character wide movements so what was at the bottom left is now one line up and in the middle of the screen. Was there a mod to the ROM for 64 wide screen? I can't go above 16x64 as I only have 1K video RAM to work with. 28 lines is the max I can get to fit on the display in 32 character wide mode. I agree 32 across is never fun and my Superboard II at 25 was even worse to deal with.

Vince

[dave]

The ROMs expects 32x32, but the ROM can be modified to support the 64 char line length. If there were some way to allocate 2K video RAM by setting a flag, then this could also be used to emulate a C2, if the 28x64 display is readable. The 28 lines would be the middle 28 lines out of the 32 in the memory map. The syn600 ROMs could also be modified to support 16x64 or 32x64, as can CEGMON, and likely also the various other replacement ROMS out there.

Dave

[Steve Gray]

Yes, for me the perfect OSI replica would support C2 / C4P with 64x32 video in 8 colours. I'm not sure how much value the expansion connector is with 3.3V. How many expansions will be created for it? I'd rather see a 5V, 40 pin DIP like on the superboard built in or made as a user populated option on-board. Most users will probably never add anything, but for those that do (like myself) it would likely be a real OSI board. And again, I'd like to see a separate keyboard. If you made it so the keyboard lines were routed properly so that the board could be cut and the keyboard removed, and connected via a ribbon cable that would be amazing....Just my 2 cents.

As-is it's still a great project, and it's nice to see OSI get a little well-needed recognition.

Steve

[vbriel]

The expansion connector is easy to adapt to 5V levels with a couple of bus chips, not a big deal at all. Some of the 6502 lines can be run on 5V now. I originally was going with the 40 pin socket connector but then people might not realize that the system is 3V and connect a 610 board to it and risk smoking the system. A 40 pin ribbon cable to an add-on board or to a prototype board would be easy to accomplish. An adapter board with bus voltage adapters could be made with the 40 pin socket. This would give the connector the exact same connection as the 600 has.

While the were many OSI system choices, I decided to clone the 600 because of its uniqueness as a single board computer with the built in keyboard. Cloning C4P's with exact components would not be too difficult except for some bus chips but the kits would then be a more difficult kit to build than my target builders (beginner to intermediate) and more expensive. I added a socket that has the keyboard matrix lines connected on it, I just need to document the socket so it could be hacked. The thought of sawing off the keyboard makes me cringe a little but I guess this was common on the 600 boards. Every kit I design I find I have to make hard choices, I try to post my work to get feedback and make some adjustments as long as it fits in the design plan. It would probably be easier to do a whole new design C4P than hack the board I've currently designed. Looking at the board layout, there are some traces that are critical (D000 address range select, A15 and D7) that if cut would cause the board to not function.

I won't rule out another OSI clone in the future but I have another project I have to pull off the shelf first. Plus I want to work on an SD card floppy emulator for the Superboard that would emulate the 610 and be able to use disk image files right off the SD card. I don't want to get into that because I haven't even started that project yet.

The board files have been submitted to the board house and I just got 20 sets of 53 key keyboard caps from the company that makes them for me. I'll probably do small runs of 20 at a time to judge demand of these kits. I'm writing the manual but except for the BREAK key feature, it is a OSI 600 in functionality.

[Jeff]

LOL. The thought of Sawing off the keyboard made me cringe too! No offense.

Maybe for the C4P replica it could be done in a Mac Mini form factor. Kind of supply your own keyboard and screen. The usb could be power and serial I/O at the same time.

I just find that I can't type on that old layout anymore. The keys are in the wrong place!! Having said that, I indend to put my SB3 into a reproduction C1P case.