After a few different designs and trials I think I’ve finally settled on something I like.
I’ve pretty much got double sided boards sorted but making vias are a pain but it works and looks OK.
As you can see this is destined to be fitted in Stiggy’s machine. It still needs cut down to size but im happy with that.
Sorry, I wont be making these for other people so please don’t ask.
This fancy litle thing arrived today.
It was still sealed so was a little bit of a shame to open it but whats the point in that really?
The box included a cartridge, a user port device and a serial port device
Since I love hardware I couldnt resist opening up the cartridge for a peek. Not sure what I expected to find, maybe something fancy and cool? Not likely.
I tried to open the user port device up but the screws have been deliberately sheared but there is a hole at the top where you can see in and it just looks like a load of the lower contacts are soldered together, terminals B – M according to the allpinouts.org.
One strange quirk about this adapter is it doesn’t fully fit into the user port due to the size of the case the edge connector is housed in, you have to kind of mash it in and hope for the best.
The serial port device is also the same but am unable to make out whats connected yet but its very easy to make your own up.
Running the cartridge brings up a nice keyboard test screen where you can press each key on the keyboard and it lights up the relevant key pressed
Pressing the RESTORE key moves on to the Joystick test
And finally onto the computer checks
I didnt have any of the adapter devices plugged in here but they do work, whether they prove anything or not in the event of a real failure remains to be seen.
The manual is pretty informative containing possible problems for each error very similar to the superb info Ray Carlsen has on his site.
There is also a load of order forms for different “Doctor” products for the C64
After a few seconds of google searching I found a ROM dump for this cartridge so it is entirely possible to make up a set of your own should you feel the need to.
Today I found a PLS153 and a couple of PAL16L8 IC’s on my old Mortal Kombat board.
I have added the original PLS153 dump and also reworked it to work with my GAL adapter, both are in the Downloads section.
The 2 PALs were protected so these were dumped with the Boardmaster.
If any of these IC’s are missing from the board, it will not boot at all.
The manual for MK states the following for the chips:
5346-40025-2 => PLD Address Decode
5346-40025-3 => PLD Video RAM Control
5346-40025-4 => PLD Local Control
These have all been tested
A little while back I made up an adapter for the PLS153 so I could use a GAL22V10 in its place providing the JED file was reworked.
I made the adapter on veroboard but now I can do basic prototyping using copper clad boards I thought id make a proper one up.
The design only took 5 or so minutes in Eagle CAD and after a quick sanity check I printed and transferred it to a board.
And a little while later it was etched and time to drill this thing out.
I fitted sockets where needed and took a few comparison photos with the old proto one.
(or is it GAL2PLS?)
Time to run the game, works perfect. Im happy with this, I can now replace these parts reliably should I need to.
Today I received a ZXpand with AY sound add-on.
This is a really useful SDcard device for the ZX81 made by my pal Charlie Robson.
Havent had a chance to mess around with mine today but ive used one at RCM and have been most impressed.
Ill post more on it when I get time over Christmas