On Fri, Apr 6, 2012 at 5:53 AM, Sander Reiche <sander.reiche at gmail.com> wrote: coffee -> monitor -ethan

I think a bit of Virginia Round-leaf Birch looks nice with the SX64. Rosewood tends to clash...

I don't think it is that hard to make, but both my SX64 doesn't have this piece. The keyboard SEEMS easy to emulate. I'd have to grab mine and take a look. Unfortunately, I'm in the middle of a huge confusion, where a job was cancelled, I have to move from my apartament until monday and have no money and no job :) I think it will take some time :)

On Fri, Apr 6, 2012 at 1:09 PM, Alexandre Souza - Listas <pu1bzz.listas at gmail.com> wrote: I would recommend a parametric CAD like OpenSCAD or FreeCAD to generate the shape. IIRC, it should be a small number of "cubes" subtracted from other cubes, so that's easy to code up. It's a passive switch matrix, like the C-64 and VIC-20 and PET, and since the ROMs are fundamentally the same as a C-64 (yes there are differences but I don't think they apply to the keyboard scanning routine), one could take a C-64 keyboard and wire up a DB25 adapter. Not portable, but it would work. For a "modern" keyboard, I'd recommend something like Jim Brain's adapter that has a silicon crossbar switch. We've been over that sort of thing on the list before, but the design constraints are that the scan routine runs every clock 'tick' (16.67ms on any C= NTSC machine) and strobes the matrix in a few uS, plus in the case of the C-64, the keyboard shares lines with the joysticks, so any keyboard adapter should play nice with those lines in particular. I don't think many people did in-the-box hacks with the keyboard scan lines, so as long as the IRQ scan routine works and the joysticks work, that would be a successful emulator. There are several techniques to do it; a silicon crossbar switch is a low-effort one. That's unfortunate. I hope some good news comes your way. -ethan

On Fri, Apr 06, 2012 at 04:41:47PM -0300, Alexandre Souza - Listas wrote: I tried that about 2 years ago using an ATmega644. It nearly worked, but when the C64 switched from one keyboard row to the next the ATmega644 generated several pin change interrupts. This took too long to process and the C64 got the wrong answer. Maybe one day I will look into faster processors but the ones I know about are quite slow at I/O. The timing of the NMI routine (for checking RUN/STOP when RESTORE is pressed) is even tighter than the normal IRQ. S?ren

On 4/7/2012 10:47 AM, David Riley wrote: I'd be interested in any successes, as I was unsuccessful as well. I could try again with the mbed (cortex m3), but I am not hopeful. The worst case scenario is a KB event simultaneous with a joystick event. Filtering out the joystick events was my big issue: * seeing a low event happen on what would normally be the input pins, and trying to decide if that was caused by the joystick or a custom scan routine that uses the input lines as the output lines * Having the joystick or the POT selection lines be accessed while in the middle of servicing a IRQ for the KB lines. I found DIP 8x16 analog crosspoint switches (http://www.futurlec.com/Zarlink/MT8816AEpr.shtml) for a more reasonable price (still high than I'd prefer), if anyone is interested. Jim -- Jim Brain brain at jbrain.com www.jbrain.com

On Fri, 6 Apr 2012, Tony Duell wrote: It's an L-shaped block. __ cable goes in here --> | |__ |_____| <-- male DB25 sticks out here I figure it could be made like this: Take a square billet and route out a groove to get the L shape. Slice it into pieces. Machine out a compartment for the DB25 and cut a groove from the cable entry to the compartment. Put the cable and DB25 in the compartment and run the cable where it needs to go, then fill with epoxy and smooth it out. -- David Griffith dgriffi at cs.csubak.edu A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?