6502.org

Howdy...

I wanted to do a fun project with the W65C816SXB board so I decided to add Keyboard, VGA and Sound.
I got a couple of W65C22 for this project, the first W65C22 will be used to read the keyboard, the second one for VGA and sound using the Propeller project earlier.

Just got started, I'll keep you updated...

Made some good progress over the weekend...

Got the C=64 keyboard hooked up to the first VIA and I can read the key matrix...
Code still pretty rough but it seem to be working.

I also added files to GitHub,
https://github.com/alamorobotics/W65C81 ... rd_VGA_SID

Got another VIA added, it will be used to communicate with the Propeller to generate VGA and sound...

Need to take a break from soldering and refresh my Eagle skills so I can make up the schematics...

Got the first schematics added to GitHub...

https://github.com/alamorobotics/W65C81 ... rd_VGA_SID

What is that schematic software so many use? Can the default colors be changed? That gray writing is awfully hard to read!!

Looks like CadSoft Eagle.

Thanks. I just wrote to them about it.

I usually export circuit diagrams from eagle with the monochrome option set.

You can also use the 'Black' option in the print to PDF/Postscript dialog.

In addition, all colors in the schematic editor can be customized.

Can you post that in monochrome, please, for the benefit of the old, color-blind folks around here?

Howdy...

Here is the monochrome version of the schematics.
I added the Propeller and 3.3V power supply over lunch.

Is there a way to export to PDF ?
That would probably be even better.
Still learning Eagle cad...

I have Adobe Acrobat Standard installed on my Windows box, which appears to programs as a printer. Not sure what other methods might work for you.

BTW, diodes D9 and D10 should be Schottkys. The forward drop of the 1N4148 will likely prevent the 65C22s' IRQB output from pulling the MPU's IRQB input low enough to be recognized as an interrupt.

Yes, go to the Print menu, and in the printer selection choose "Print to File (PDF)". If you have more than 1 sheet, don't forget to select "All", otherwise it will only print the first sheet.

Howdy...

I finished up the Propeller schematics and did a print to PDF, I think this would be the best way to post schematics.
Or do we prefer the monochrome ?

I'm not sure why there are diodes on the IRQ for the W65C22, the schematics I copied had them so I threw them in there...
http://www.westerndesigncenter.com/wdc/ ... 816SXB.pdf
They should not cause me any problems since I don't plan to use the IRQ for now..

Any thoughts about the diodes ?

I address them on the 6502 primer page in IRQ/NMI connections, starting at about the middle of the page, at http://wilsonminesco.com/6502primer/IRQconx.html .