May 202019
 

Another reproduction of a custom IC successfully carried out.The part in question is the Sega ‘315-5025’, a 300 mil DIP18 chip found on System 1/2 boards, Space Harrier and other Sega hardware from 80s :

It’s basically a shift register used for graphics functions being directly connected to data bus of the ROMs as per Choplifter schematics (it’s shown as a 20 pin IC because it’s compatible with the bigger ‘315-5155’ found on System 16A and Out Run boards)

 

Since nobody made it before I reproduced this custom my way by studying how it was reverse-engineered in bootlegs:

Testing on a Pitfall II PCB:

I hope this will help people to repair their faulty PCBs being understood that this project, like all my other, will not be made public although nowadays it’s a common thought that everything should be shared and free.Nothing in life is free and if you don’t work for it you certainly shouldn’t expect it, nor do you deserve it for free.

 Posted by at 9:43 pm
May 192019
 

‘Konami-1’, a simple name given to a custom IC used on many Konami PCBs from early 80s, here’s a filtered list from MAME :

The chip itself is a 600mil DIP42 which most of times comes with scratched-off part name:

It’s basically a 6809 CPU with some minor modifications (different pinout and scrambled opcodes), it was the first custom chip ever produced by this manufacturer.

Studying how it was reverse-engineered by bootleggers I made my own reproduction of it :

Here’s testing on a Jail Break and Gyruss (bootleg) PCBs:

Probably a CPLD based version will come later in order to semplify the board layout but I’m quite happy with it as is.

 Posted by at 11:34 am
Apr 292019
 

It’s big, black and squared.We are talking of the ’85H001′, a custom IC you can find on some arcade PCBs manufactured by Capcom like Ghosts’n Goblins, Legendary Wings, Section Z, Trojan, Gun.Smoke.It looks like a module with audio functions, two versions have been made.A ceramic unmarked one :

And a plastic/epoxydic one marked ’85H001 5H’ or ’85H001 5I’ :

Technically speaking the ’85H001′ can be considered a nearly complete digital sound system, all typical components (CPU, RAM, address decoder, etc.) are embedded into it with the exception of the ROM and synth ICs which are external.Actually the ’85H001′ has been already reproduced by ‘Apocalypse’ who made an excellent thru-hole version :

You can read more about in his blog :

http://arcadefixer.blogspot.com/2018/02/capcom-85h001-sound-module-reproduction.html

http://arcadefixer.blogspot.com/2018/07/capcom-85h001-sound-module-reproduction.html

 

Having found recently  a bootleg of Ghost’n Goblins with a module replacement I decided to make my own reproduction and I made two versions.An ‘hybrid’ one with thru-hole Z80 CPU/RAM and surface mounted ICs  :

And a full SMT version with Z84C0006 CPU (PQPF44 package)

Here’s final testing of both on my original Gun.Smoke PCB:

 

 Posted by at 6:41 pm
Apr 282019
 

The Konami  ‘501’ is one of the many custom ICs you probaby encountered when dealing with PCBs from this manufacturer.Most of times the chip (28 pin 600 mil DIP package) comes with scratched-off part name, sometimes not like on my Rush’n Attack PCB:

It can be found on not so many PCBs like shown on this useful spreadsheet (credits to ‘mattosborn’ on KLOV forums)

https://docs.google.com/spreadsheets/d/1iB9BJaEpAufgKaz758FiDDekUH8JreoTn276yPqD-kk/edit#gid=0

Actually there is already a reproduction of it which uses the ColinD CPLD 28 pin board (based on Altera EPM7064S)  of which ‘Porchy’ wrote the code (available here for download).I simply made what I call a ‘poor man’s’ version using simple surface mounted TTLs gates:

Here’s final testing on the Rush’n Attack PCB:

 Posted by at 5:06 pm
Apr 262019
 

Code name : ’86S100′.Nothing really ‘TOP SECRET ‘, just a little custom IC you can find on many Capcom arcade PCBs from pre-CPS1 era.To name few :

  • 1943
  • Bionic Commando
  • Black Tiger/Black Dragon
  • Mad Gear
  • Rush & Crash/The Speed Rumbler
  • Side Arms
  • Street Fighter

The chip is a 28 pin one with plastic package and pitch of 1.778mm :

Sometimes you can find it under different part name but same functions, like on a Mad Gear PCB :

This custom IC is involved in graphics generation being directly connected to data bus of the GFX ROMs as shown on Bionic Commando schematics:

Being a not really reliable part (sometimes you can find it literally ‘fried’) and quite hard to obtain as spare I decided to give a try to reproduce it.As usual I looked at how bootlegers re-engineered it and how the custom functions were implemented in earlier Capcom hardware.I succeeded in my purpose it but I actually had to make two versions of it because the original ’86S100′ can work in two modes depending on the logical state of its pin 1 (if hard-wired to GND or VCC).

Here’s final testing of both reproductions on a Bionic Commando and 1943 PCBs:

 

 Posted by at 7:29 pm