Search found 15 matches

by thedevworks
Fri Mar 22, 2019 12:40 pm
Forum: ZX BASIC
Topic: 1k bouncing ball
Replies: 5
Views: 474

Re: 1k bouncing ball

https://youtu.be/EJCFu95eAxI


Nice :) Fun.. Thanks!
by thedevworks
Thu Mar 21, 2019 9:59 pm
Forum: Hardware
Topic: Keyboard Issues .. Some keys not working (new membrane)
Replies: 11
Views: 139

Re: Keyboard Issues .. Some keys not working (new membrane)

Ok so that was a clue.. I found a short but couldnt see where.. I ended up purchasing a microscope, and within 10 minutes of setting it up I saw the issue. https://i.ibb.co/X7Psq3G/closeup.jpg Scraped it with an x-acto knife a tiny bit.. and the whole keyboard works! Now, it crashes when loading fro...
by thedevworks
Wed Mar 20, 2019 6:03 pm
Forum: Hardware
Topic: Keyboard Issues .. Some keys not working (new membrane)
Replies: 11
Views: 139

Re: Keyboard Issues .. Some keys not working (new membrane)

Thanks for the replies again all! At this point I'd not even thought of getting my multimeter out despite using it to do initial tests ! :) I'm pretty new to this and learning a lot as I go, these small hints send me down a path that I can investigate and learn more. (I've been working my way throug...
by thedevworks
Wed Mar 20, 2019 2:07 pm
Forum: Hardware
Topic: Keyboard Issues .. Some keys not working (new membrane)
Replies: 11
Views: 139

Re: Keyboard Issues .. Some keys not working (new membrane)

the latest list is; 3 E D X 8 I K M looking at the schematic (Is there anything better for the issue one?) http://www.zx81.de/bilder/ts1500_600.gif All the faulty keys run to KBD2 on the ULA. So, with that In mind I traced it on the board and made sure the soldered joint was all good So, the situati...
by thedevworks
Wed Mar 20, 2019 1:59 pm
Forum: Hardware
Topic: Keyboard Issues .. Some keys not working (new membrane)
Replies: 11
Views: 139

Re: Keyboard Issues .. Some keys not working (new membrane)

Aha thanks for that idea. I tried that and pretty much get the same issue (Apart from 1-5 were actually working. And most of the 'duff' keypresses cause a crash. So I guess next step is to try and log which combinations are duff and map that to a schematic to figure out the cause. \ My concern with ...
by thedevworks
Wed Mar 20, 2019 8:18 am
Forum: Hardware
Topic: Keyboard Issues .. Some keys not working (new membrane)
Replies: 11
Views: 139

Re: Keyboard Issues .. Some keys not working (new membrane)

Oops sorry, zx81 Issue One !
by thedevworks
Tue Mar 19, 2019 11:06 pm
Forum: Hardware
Topic: Keyboard Issues .. Some keys not working (new membrane)
Replies: 11
Views: 139

Keyboard Issues .. Some keys not working (new membrane)

Hey all .. again.. I recently added a new ULA and a new keyboard membrane.. but some keys are not working. Tried reheating the ULA joins and still same .. but perhaps I can identify the issue to a pin. 8 actually causes the whole thing to crash.. but the following keys don't work at all ; 1 2 3 4 5 ...
by thedevworks
Thu Mar 14, 2019 12:33 am
Forum: Hardware
Topic: Hello All & Dead ZX .. probably
Replies: 16
Views: 491

Re: Hello All & Dead ZX .. probably

Image

:P :P :P :D :D :D
by thedevworks
Thu Mar 14, 2019 12:31 am
Forum: Hardware
Topic: Hello All & Dead ZX .. probably
Replies: 16
Views: 491

Re: Hello All & Dead ZX .. probably

Ok I was wrong, the new ULA does work!! Keyboard is a bit iffy, but for now, I'm happy! :D
by thedevworks
Wed Mar 13, 2019 6:10 pm
Forum: Hardware
Topic: Hello All & Dead ZX .. probably
Replies: 16
Views: 491

Re: Hello All & Dead ZX .. probably

Oh well, I tried first the CCB because it was the least disruptive, which didnt work, followed by a new ULA, which also results in the same video signal. I guess now the only thing left to do is replace the other chips!