CD32 controller Up doesn't work!

[lord of time]

Hi, so I got my hands on a CD32 controller only to discover that UP dosnt work... so I opened it up checked the rubber contact, checked continuity to the up trace all the way down to the controller connector and the cable is fine - i also know its not my CD32 as I have tried it on my 1200, and my 600 too! any ideas?

[DDNI]

Before the real techies wake up...
I have read that a very temporary/test hack is to scribble on the contacts with a soft pencil, then test the button... Possibly an old wives tale, but maybe worth a try?

[Jope]

I prefer isopropanol on the PCB contacts and a few gentle wipes of the black rubber under the button against a piece of copier paper if they look shiny.

Graphite only makes a mess.

[Daedalus]

Check the resistance to ground of that contact when pressed, and compare it to one of the working directions. The paper trick mentioned often works well, but if it doesn't and the resistance is still very high, you can buy small bottles of resin that you paint onto the rubber pad and cure for 24 hours. It's flexible enough to survive normal use - I've used it to revive many worn out remote controls.

[lord of time]

Ok guys tried your tips, and tried rotating the rubber pad contact so its one of the working ones pressing the up part of the pcb - still no go... there is something funky going on!

[lord of time]

I have found another problem and am starting to think the shift register might be fubar? I tried the controller on a actual game with CD32 controller support - Treasure Island Dizzy WHDload version with the tool type Custom=3 (enable cd32 controller support) the game quits as soon as it loads, I tried the game without this tool type and no quit so it got me wondering what button on the CD32 is defined as the Quit key? answer is the start button... you know the grey rubber one! well at this point its a bare pcb and i am activating the contacts with a single rubber pad so I know its nothing mechanical, I once again checked continuity on every wire in the cable and its all fine so does anybody know if the 74ls165n is known to go wonkey?

[supaduper]

Originally Posted by lord of time

does anybody know if the 74ls165n is known to go wonkey?

Well if its anything like the 74ls166 shift reg on the CD32 mobo then yes it can fail easily

[lord of time]

ok i will buy a couple and swap it out - i will report back my findings.

[lord of time]

so my chips finally arrived today and i tried piggy backing it over the one soldered to the pcb before i commit to desoldering and it made the pad have the start button perminately pushed! so i am at a loss!