Today I’ve uploaded the latest version on my BINman software to v4.5.0
The main addition here is the inclusion of Fluke 9010 signatures to the checksum area.
Not only does it have support for the 8 bit signatures it also supports the 16 bit signatures.
For 16 bit signatures, it will only support single files so if your hardware has the files across 2 EPROM’s then these will need interleaved or whatever is required to merge them.
Enjoy
Received an ESP Ra.De. board for repair for my friend Vic.
This was the video I was sent originally
This PCB had apparently had work done before but all we knew was the big 240 pin custom chip had been reflowed. This always makes me nervous because if it was destroyed somehow then all further attempts of repair would be for nothing unless I had a donor.
Visual check carried out of the board in general revealed nothing bad so hooked it up to the test. As expected we have no sync and the game does not appear to be running either. I confirmed this as the watchdog was kicking in.
Using the scope I probed the sync pin at the JAMMA connector and found a low sync signal of 13khz.
I started tracing the signal back but it went to the big custom chip that I already knew had been worked on, I also confirmed the main clocks and signal to the custom chip.
With no other ideas at this point I decided to tackle the game booting issue. The 68000 CPU was already in a socket so using the Fluke 9010 with a 68000 POD (Thanks Caius for the extended loan of his POD) I could start troubleshooting.
First off a BUS check revealed data bit 2 was tied low. In actual fact data bits 2 and 3 were shorted together.
I started tracing all the point where these data lines go and one by one started isolating them from the circuit. Once again my search led back to this big custom chip.
Reflowing these two pins on the custom cleared the fault.
At this point I took a closer look at this custom and found if I got the light in at the right angle I could see a lot of dried flux underneath.
Over time flux residue will dry out if not properly cleaned and it can go conductive.
I cleaned this and the bus test now passes. The ROM check between 0x0 – 0x7FFFF should be 1BBA which also passed.
The main RAM lies at location U39 & U40, 0x100000, 0x10FFFF. The Fluke reported a decode error on bit 1 which basically means there is a problem with the address lines.
Doing some manual reads and writes I could see that bit 1 of RAM U39 did not work. I replaced this and retested which then went OK.
I started my way through the rest of the RAM location as per the MAME driver.
The sprite RAM lies at U43 & U44, 0x400000, 0x40FFFF. Once again the fluke reported bits 5 & 6 tied together and once again I was led back to the same custom chip.
From here I just opted to reflow the whole chip. This cleared the issue with the sprite RAM. All other VRAM passed tests.
Retesting the PCB now resulted in a nice looking game for the most part but there was a strange strobing around test and lines that were white. Going into the test mode made this very obvious.
I couldn’t get a good video of this as it all looked fine on a camera.
To began with I thought this was all to do with my test monitor and the sync being a tiny bit high for it but I tested it on all my monitors and cabs and they all gave strange results.
I eventually went back to that custom chip and inspected all the pins again.
I couldn’t visually see anything but checking continuity on all pins against the adjacent pins revealed a short somewhere around pin 190. A further reflow of these pins resulted in a completed repair
One strange thing about this board is that on boot up it stays in a reset state for around 2 seconds which is the point where the sync reads 13khz. After that the sync steps up to 15.23khz and all OK.
Here is a layout of all the RAM locations on the PCB
Received a Parodius DA! PCB for repair, a shoot’em up and second title in the Parodius Series produced by Konami :
Board booted up and game was fully playable with sound but sprites were wrong:
First of all I launched a MASK ROM check which reported two bad devices @K2 and K8 :
They are, indeed, 4Mbit MASK ROMs that store sprite data processed then by the near ‘053244’ and ‘053245’ custom ASICs :
The result of the check didn’t imply the devices were really bad but also that they could be not reached.So I went to probe them and found that pin 1 of the MASK ROM @K2 was floating while same pin of the one @K8 was active :
Pin 1 is the highest address line of the MASK ROM and should be in common between the two devices whereas, at quick check with a multimeter, it was not.Hence the trace to pin 1 of device @K2 was interrupted somewhere.I added a jumper wire on solder side:
This did the trick, sprites were restored and board 100% working again.Repair accomplished.
I had a couple of original Capcom ‘1942’ PCBs lying around which I never tested due to the lack of a proper JAMMA adapter (game uses an unique pinout which is not the Capcom Classics one).Recently I had chance to build the adapter and try the boards out, it turned out both were faulty.
The first set was in good shape in its CPU board :
And VIDEO board:
It even booted up and played with sound too but sprites (planes) were totally absent:
The faulty was obviously located on VIDEO board so I went through schematics and found a part of the object circuit highlighted with an handwritten note saying “NO PLANES”
The circled section concerned two NAND gates of a 74LS00 @N8 which generates two signals labeled ‘1WR’ and ‘2WR’.When I probed the inputs I found pin 9 and 4 stuck HIGH:
These inputs come from outputs of a 74LS139 @N10 which had its pin 1 floating:
Pin 1 is the enable input of the decoder and comes from output pin 5 of a 74LS174 @N11 :
Pin 5 of this 74LS174 was indeed floating, stuck at undefined voltage level of +1.64V :
But the input pin 4 was active :
This is a typical way of failure of Fujitsu TTLs and the part was from this manufacturer hence , sure enough, I removed the chip.It miserably failed the out-of-circuit testing:
Replacing it restored the sprites :
First board fixed.
The second set was in good shape too :
But it booted to a static garbage screen :
Probing the Z80 main CPU revealed clock input (pin 6) was stuck high:
With the help of schematics I traced the clock input back to pin 7 of a 74LS174 @H6 located on CPU board, chip was again from Fujitsu :
Input pin 6 was correctly receiving a 3 MHz signal:
I made piggybacking with a good known IC and board succesfully booted into game:
Chip obviously failed the out-of-circuit testing:
Replacing it fixed board completely.Double repair job done.
I got this Bombjack Bootleg board a while back when I just couldn’t find any original boards for my cab. I since got an original board for it but this bootleg has been left for repair since then.
It was sold as “graphic & sound issues” without more explanations. Lucky though, these bootlegs are identical to the original boards.
A first visual inspection reveals a few loose & broken filter capacitors and a couple of messy traces near the edge connectors. Hard to say without a magnifier if they’re broken. The caps won’t be an issue for now so let’s focus on the traces
I could do a quick continuity test but as it happens, somebody sent me one of those cheap chinese microscope things. They’re essentially a USB webcam , so this is a good opportunity to give it a test.
Indeed two traces were broken, a quick solder bridge will fix that. Handy little toy that thing!
Next, I had to make an adapter since the board didn’t come with one.
On these boards the video signal comes from a separate connector on the far edge of the board. You can already spot there’s an IC missing there too
This might explain the graphic issue.
But first let’s finally power the board and check what we get.
So our colors are off, some graphic information is missing. There’s no sound coming from the board either. The wavy effect on top of the screen is an artifact of my monitor being in need of a re-cap so we can ignore this.
Let’s first take care of that missing IC. Looking at a photo found online, this should be an LS174 flip-flop.
I then checked the schematics and this confirms it as a pair of these is handling the color signals. Our missing IC at 8B handles the blue and part of the green signal.
Let’s drop a fresh one and see if this restores our picture.
Success!!
Now to address the sound issue. Probing my way from the amp back I eventually realized I’was not getting any signal. All outputs on the sound ICs (three AY-3-8910) were dead , I suspected the z80 controlling these.
Swapping it with a new working one restored the sound completely board … here’s a photo for proof :
In addition to this I did make a couple of mistake on my adapter, meaning the controls worked incorrectly. I spent some time trying to troubleshoot this till I double checked my adapter. ah well. Another case where having another working set would prove useful.
Anyway the board is working fine now, but while I tidied a few loose capacitors around the board I spotted this unpopulated section of the bootleg board:
Silk screen and holes for two leds and resistors. Comparing to an original board and checking the schematics, these should be indicators for the 5v and 12v lines.
While this is not strictly needed it’s an easy thing to just add them . I went for a green 5V and red for 12V
yay . a fully working Bomb Jack bootleg.
And for those preferring the video format: