Porchy

Operation Wolf repair log #6

 PCB Repair Logs, Repair Logs  Comments Off on Operation Wolf repair log #6
Jul 252021
 

Got a familiar Operation Wolf PCB that I offered to look at for a friend.
I’ve had this board several time over its life and this new fault was “no sound”. The sound actually stopped working when the owner hit the start button but the game could still be played.
I found the fault really quickly. Starting at the CPU I checked all the signals on the Z80.
Everything was doing what it should be doing except for the /NMI pin (pin 17) which was stuck high all the time.

The NMI is used to signal to the sound CPU to start playing a sound. The signal is generated by the custom PC060 chip nearby on pin 12

I transplanted the custom from my Rainbow Islands PCB to test and the sound all came right back.
Here you can see and hear the /NMI pulse as a new sound plays

So now I’ve confirmed the device at fault what do I do for a replacement. I have no scrap boards with one available. Furrtek has recreated the operation of this device and Caius has made a CPLD replacement that uses this code.
I’ve recapped the sound section and Caius is sending me a replacement but for now I’m happy that this is working again.

 Posted by at 6:24 pm

PLD Archive domain update

 General  Comments Off on PLD Archive domain update
Feb 232021
 

As of yesterday the PLD Archive wiki was locked for editing and it has been moved to the new domain of wiki.pldarchive.co.uk.
The link on this site has been updated but if you have bookmarks saved or whatever then these will need updated too.
As usual there will likely be broken links and errors so if you happen to find any then please do let me know. There is an email link on the main page of the new wiki. Likewise, if anyone has any PLD dumps or recreations, PCB pictures or IC pictures to contribute please also use that new email address to send them in.

Thank you

 Posted by at 5:41 pm

Taito PC080 & PC090 info

 Technical Info  Comments Off on Taito PC080 & PC090 info
Dec 302020
 

Channelmaniac has put together a couple of drawings to show the pinouts for the Taito PC080 and PC090 customs

Thanks again to Channelmaniac

 Posted by at 4:16 pm

Konami 054539 info

 Technical Info  Comments Off on Konami 054539 info
Dec 062020
 

Channelmaniac kindly sent me some tech info he made up recently for the 054539 custom found on some Konami boards.
Here we have the pinout for the chip and also the circuit conenctions
Thanks to Channelmaniac for sharing these

 Posted by at 6:43 am
Oct 062020
 

Over the last few months I’ve had tons of messages from readers of this blog asking about the lack of updates and all sorts of nice words so I think its time to address this officially here.
My interest in arcade repairs has pretty much dwindled down to nothing over the last 12 months or so and I have found myself finding a love for other hobbies which I am throwing myself into and loving them more and more.
That doesn’t really leave me with much free time for repairs and it certainly doesn’t leave me with any time to write up a detailed blog post about it either.
Right now, my official status on this is I wont be doing anymore repairs logs.
With that said I do put a lot of time and effort into dealing with PAL’s and will still be maintaining the WIKI and the blog will still stay with that too.

If the time comes that I wont be continuing with the site then it will either all be handed over to someone else that is willing to keep the information going or it will be saved and made available via other methods. I’m not going to let the last 10 years of work from myself and other contributors disappear.

Any of the other contributors can still post here if they wish and if anyone else wants to contribute then I will create an account for them too

I hope that puts a few minds at ease

 Posted by at 6:16 pm