Caius

Jul 142018
 

The ‘007593’ and ‘007327’ are two custom ICs found on many PCBs manufactured by Konami in end 80s.This should be a complete list:

‘007593’ on :

  • Black Panther
  • Contra / Gryzor
  • Hyper Crash
  • City Bomber
  • Kitten Kaboodle / Nyan Nyan Panic
  • Labyrinth Runner/Trick Trap
  • Vulcan Venture / Gradius 2

‘007327’ on :

  • Combat School /Boot Camp
  • Rock ‘n Rage
  • Jackal/Top gunner
  • Flak Attack
  • Devil World / Dark Adventure
  • Double Dribble
  • Rack ‘Em Up/The Hustler
  • Haunted Castle
  • Super Contra
  • Battlantis
  • Blades of Steel

Both ICs have strong similarities starting with how they appear:

Analogous package apart, they have same function as we can see from schematics:

But the ‘007593’ and ‘007327’ are not simple RGB DAC as  you can think of at first glance but they embed a complete palette color circuitry on a single chip.So not only RAMs but, as you can see, many other ICs in form of bare dies covered by coating as well passive parts :

Therefore, for this reproduction project I used a different approach.I studied previous Konami hardware figuring out how the color palette circuit was engineered without the use of the customs.After drawed my schematics I reproduced the ‘007593’ for first:

Once successful tested,  it was the turn of the similar ‘007327’ :

Testing on their respective boards:

The layout of both reproductions could be surely optimized (with consequent reduction of the size of the board) using moderm complex programmable logics but I’m happy enough with them since my primary goal was to study a working replacement for these two custom ICs which seems quite prone to failure making our beloved PCBs unusable.

 Posted by at 12:11 pm
Jul 132018
 

Recently I decided to take a look at another custom IC, the Taito ‘PC030CM’:

It’s a 20 pin chip in a brown-ish SIL package used on some PCBs like Arkanoid, Bubble Bobble, Big Event Golf and few other.Like schematics shows, the ‘PC030CM’ handles coin inputs as well counters/lockouts:

If the part fails (most of times it breaks due its fragile nature), the board will no longer boot, an ‘I.O ERROR.’ is all you will get:

For this reproduction project I had no need to inspect or analyze the part but I simply re-engineered,using SMT devices, a replacement board that can be found on some Arkanoid bootlegs:

Then I compared my schematics to work previously done by ‘JROK’ on KLOV forums and, once verified everything, I  designed a proper PCB.Here’s the reproduction how looks fully assembled (I ordered it with red soldermask but manufacturer wrongly made it blue)

For the testing the user ‘manimani’ on Neo-Arcadia forum kindly sold me an original Arkanoid PCB :

The board was missing the ‘PC030CM’ custom :

Some workaround was made in such a way that the board could coin up the same using the SERVICE button instead :

So, this was a perfect platform test for my reproduction which worked fine:

Thanks again to ‘manimani’ and ‘JROK’.See you at my next reproduction project.

 Posted by at 10:07 am
Jul 122018
 

Received from Austria this Devastators PCB (manufactured by Konami in the distant 1988)

The board was constantly watchdogging sign that no valid code was executed :

Probing the HD63C09E main CPU revelead some address lines were dead:

I removed it :

Trying the CPU in another board confirmed it was really bad so I replaced it.The board booted up but it was failing the POST showing two bad devices which at fist glance I could not recognize due the complete lack of graphics :

Thanks to MAME I figured out they were the ones @C11 and C14 :

On PCB they are the two 2k x 8-bit static RAMs (Motorola MCM2016 used) which are part of the palette colors circuit

Probing the one @C14 revealed stuck data signals:

RAM chip failed the out-of-circuit testing:

Now the board booted into game but with severe graphics issue : the backgrounds had wrong colors and sprites were missing.Sound was absent too:

I dumped the four OTP MASK ROMs that store tiles data and found three bad ones :

But this made no real improvements.Board is almost fully populated with Fuitsu TTLs so I went to test them in-circuit with a logic comparator starting from this part of circuit which is involved in color generation  :

I found five bad mutiplexers with floating outputs:

This restored correct backgrounds:

I decided to troubleshoot for first the lack of sound.Found in rapid succession these bad ICs:

  • YM2151 (with serial data output pin stuck high)
  • sound RAM and ROM
  • two 74LS74 @G5-F10

And a 74LS273 @B7 with some floating outputs:

Sound was back :

Now the lack of sprites.MASK ROMs check reported two bad devices @H4-K4 which are the ones  storing sprites data:

This particular PCB uses a bottom ROM board with sprites and audio samples ROMs :

But the top board can also host three 4Mbit devices for the same data so you can get rid of the ROM board :

This is what I opted instead of troubleshooting it since all the splitted ROMs were soldered in.I programmed three 27C400 EPROMs with MAME dumps:

The last issue I had to fix was releated to inputs, P1 UP was not working.Using schematics I quickly found and replaced a 74LS253 @E13 with a bad ouput :

Board finally 100% fixed and another battle won against Evil Konami and Fujitsu with this big booty:

 

 Posted by at 6:14 pm

Cabal joystick sub board reproduction

 Reproductions  Comments Off on Cabal joystick sub board reproduction
Jun 102018
 

This is a simple reproduction I made of the joystick sub board you can find on Cabal PCBs.

I kept the original design of the original sub board which is this:

With the only difference I put the 74LS244 on top of PCB:

The reproduction is something not really great perhaps, someone else already made it it the past like Elgen:

http://elgensrepairs.blogspot.com/2013/04/tad-cabal-trackball-to-joystick.html

But it’s useful if you want to convert a Cabal PCB from trackball to joystick version using at same time the proper ROM set.

That’s all, simple but effective!

 Posted by at 9:17 am

Seibu ‘HB-45A’ reproduction

 Reproductions  Comments Off on Seibu ‘HB-45A’ reproduction
Jun 082018
 

The ‘HB-45A’ is a custom IC used on some PCBs manufactured by Seibu like Raiden II/DX and SPI motherboard.It can be considered  an evolution of the ‘HB-41’ that we already treated in a past article:

Seibu ‘HB-41’ reproduction

It shares the same 20 pin SIL package embedding most of the analog sound system.Its function is to mix and pre-amplify both music and sound FXs :

Here’s how it look “naked” of its external coating:

Design is almost identical to its predecessor with the presence of two OP-AMPs (a dual and a quad one) although they operate from a single supply (+12V)  and not dual (+5V/-5V) like the ‘HB-41’.All other components are ceramic/tantalum capacitors and resistors (surface mounted and printed film ones) which are part of the application circuit of the two OP-AMPs

It took some time to draw schematics not without some difficulty due the presence of some hidden printed film resistors located under the quad OP-AMP:

Schematics were then routed to a PCB which looked pretty good on a 3D preview :

The real thing assembled in all its parts :

For a while I was not able to test this reproduction due the lack of a working PCB (the “decapped” original part was taken from a dead board) until the user ‘opt2not’ from Arcade Projects and KLOV forums kindly volunteered.The test platform was his working Raiden DX PCB.He first removed the original ‘HB-45A’  in a very clean way (he used an Hakko FR-300 desoldering gun)

Installed some female 2.54mm round machined headers:

Lastly the reproduction fitted onto the board:

Then he made recordings of audio of both original custom and reproduction redirecting it to a PC from a HAS supergun using a SPDIF breakout from the  SCART connection.

Here ‘s capture using the original HB-45A:

 

Here’s the one using my reproduction:

 

Comparing the music and FXs at the beginning and end of the recordings sound identical.No differences in quality can be noticed (the slight background noise is normal when there is silence).

For this successful reproduction project I would like to thank again ‘opt2not’ for his precious testing and all material (pictures and audio captures) he provided me.I recommend you to check out his blog :

http://the-artcade.blogspot.com/

 Posted by at 9:10 pm