Porchy

[4/9/2024 UPDATE – Site No Longer Closing]

 General  Comments Off on [4/9/2024 UPDATE – Site No Longer Closing]
Apr 032024
 

After many years of arcade repairs, the time has finally come to hang up my soldering iron and move on. Its probably obvious that my interest in arcade repairs has dwindled over the last few years and with this site still taking up a lot of my space and file count, I think its time to close it down.
It will remain up until August which is when the hosting is paid up to. After this time the site will disappear so if there is anything on here that you want to keep, please make a copy of it before August.
The money saved from this will allow me to keep the PLD Archive Wiki up and running at a reasonable cost for a hobbyist.

Its been a great ride and I’ve loved most of my time in this hobby but the time has come to move on. Thank you to everyone that has ever supported me and this site and I wish you all the very best for the future.

Stay safe
Jon

 Posted by at 8:06 am
Apr 142023
 

I’ve used this cheap desoldering station for many years now. Despite its quirks and constant demand for cleaning its been a great work horse.

The an immovable blockage happened recently and I just couldn’t clear it so decided it was time to replace the element. I thought I had a spare from years ago but turns out I have ordered the wrong part.
Looking for the correct part I found it was almost the same price to buy a new gun part itself and I wouldn’t have to mess around slicing the wired inside.

New gun came and all was well in the world for around 5 minutes when the unit got stuck in a reset loop.
Obviously there was a short somewhere so set to work checking resistance until I found a shorted element.
All the wires for this thing are very tightly routed and when i pulled them out I found this

Those small breaks in insulation from being sandwiched together so tight caused my issue. A little bit of insulation tape later and I was back in business

CalcSig – Fluke 9100 support added

 General  Comments Off on CalcSig – Fluke 9100 support added
Mar 272023
 

Well its been a good long while since I last did anything with this program but now in 2023 I have got around to working on it some more.
Im (hopefully) pleased to announce Fluke 9100 signature support. The catch is, my 9100 is no longer in a working state so testing has been quite limited.
No doubt there will be issues or it might just not work properly at all so any testing that anyone can do would be appreciated.

You can download it in the Software section or direct link https://www.jammarcade.net/files/Programs/calcsig.zip

 Posted by at 8:05 pm
Oct 082022
 

Virtvic handed over his sick Bosconian PCB at a recent event for repair. I’d not seen a Bosconian before so it was interesting to delve into one and it also gave me a chance to redump the PAL chip for the Namco version as the one we have on the PLD Archive is flagged as bad.

On power up the game went through its self test process and displays “RAM OK” and sometimes “ROM OK” then reset itself and the whole process repeats itself.
The game uses 3 x Z80’s all working together which is a little bit of a pain but luckily the MAME debugger makes this a little less painless to aid in fault finding.
In the debugger I could run through the code and see what checks are performed in what order to better narrow down where my issue was.
The memory maps for each CPU are the same apart from the ROM’s for each processor. That means all the RAM is visible to all 3 CPU’s.
CPU 1 does all the RAM tests then it lifts the /RESET pin for the other 2 CPU’s which then do a ROM test for their own ROM’s and stick the result of the ROM test into the shared main RAM.
While this is happening, CPU1 is in a loop constantly checking the RAM area for a value. When the value isnt 0x0 then it either proceeds to boot the game or flags a “ROM #” error depending on which ROM has failed.
Now around 90% of the time the “ROM OK” error didnt show before resetting and I never did see a “ROM #” error.

I pulled all the ROM’s and tested them against MAME but found this to be an undumped version. Overlaying the ROM’s on an existing set I could verify that this version booted fine so they were likely good.
All the CPU’s are socketed and all the pins were also going black so removed them to look for damage and cleaned them up in the process. On replacing the CPU’s the game booted but was very flakey. Messing with the CPU sockets I could get different behaviors so was fairly convinced at this point that the sockets were bad. In hindsight I should have suspected these earlier as they are not the best

I opted to replaced all 3 even though CPU1 socket seemed to be fine.

Next boot up went great and nothing I did would make it crash again

 Posted by at 3:46 pm
Aug 212022
 

Figured as I don’t do much in the way of repairs anymore I would post about any PAL news I may have.
I’ve done too much over the last couple of years to really capture here but all of the PLD files we have have now been moved to the wiki at https://wiki.pldarchive.co.uk/ so get yourself over there if you haven’t already and check it out. It covers PLD files of any sort and for any application so if you have any you are willing to share them please get in touch.

So todays news is I have successfully recreated and tested the final two missing PAL16R8 devices from Crude Buster. These were the final two that we didn’t already have so that’s a full set available now.

CRUDE BUSTER ENTRY HERE

 Posted by at 2:51 pm