May 2017 – Page 2 – JAMMArcade.net

Hi-Lo ALL-LAB base unit PAL dumps added

PAL Updates Comments Off

May 132017

I recently bought myself a Hi-Lo ALL-11 programmer. This unit uses the original ALL-LAB base unit to connect to the outside world and also as a power supply.
Inside there are four PALCE16V8 chip. Three of them are already dumped and are out in the wild HERE
The one at U9 is registered and there cannot be recreated using our usual methods. I suspect this is also why it hasn’t been dumped before.
As the device is a PALCE there is a good chance I could reset the security fuse using my Runfei programmer. This was successful and I was able to read out the fusemap without any issues.
The registered part looks like a 4 bit binary counter and the equations show that too so I am going to mark this as ‘Assumed Working’ for now. I haven’t tested as I really wanted to get the programmer back together for some playing around with.

All the ALL-LAB PAL’s are now dumped and a copy has also been sent to the site above for inclusion.

Bells & Whistles PAL dump added

PAL Updates Comments Off

May 122017

In the past days I dumped the only PAL from a Bells & Whistles PCB (export version of Detana! Twin Bee by Konami).Original device was a secured PAL20L10 which I reversed and tested successfully into a GAL22V10.

Konami/Centuri Hypersports repair log – part 2 [ VLM5030 repair ]

May 092017

This is a very short update which covers the replacement of the VLM5030 Speech Synthesizer chip which Konami used in various games.

https://www.system16.com/hardware.php?id=556

Today my eBay order of 5 x VLM5030 Speech Synthesizer chips arrived in the mail. I only needed one but who knows when the other 4 will come in handy for future repairs.

Removed the old IC. It’s probably not clear from the picture but this IC got very hot at some point. The marks left aren’t as obvious as what I discovered under the 2149s at A19 and B19, I might need to look at those later.

I didn’t have any 40 pin sockets available but I was really itching to try this out so I soldered the chip in anyway.

Cycling through the sounds and playing them in diagnostic mode verified the fix for this. I also ran the game to verify this as well.

Vimana repair log

PCB Repair Logs, Repair Logs Comments Off

May 062017

Got this pcb from a friend for a repair.

At first it showed a OBJECT RAM ERROR which was fixed by reflowing the custom BCU-2 which had some lifted pins.

At this point the game showed all the sprites with black pixels

After some trials, I could locate the circuit which draws the sprites.

There are 4x srams 6116, by piggybacking sram @12C ( marked in white on the below pic) the sprites were shown perfectly.

After exchanging it, I got another issue

From the above picture it is difficult to see, but on the upper half of the screen, the alternate lines of the sprites were displaced on the bottom side.

I was really puzzled and I was sure that something else got broken in the meanwhile.

After some days of blindly checking other parts of the circuits, I decided to probe the address pins of the very same sram I exhanged.

A10 and A9 were tied to ground on all 4 srams of the sprite circuit, while only A8 was floating on the sram @12C

The address pins were connected to some 74LS157 and all were working correctly.

That meant the trace A8 was somewhat broken underneath.

Fortunately I had another Vimana from which I noted to which 74ls157 output A8 was connected.

After fixing the connection, the games was 100% fixed

SEGA System 16 repair log #2

PCB Repair Logs, Repair Logs Comments Off

May 052017

I received this system 16 motherboard from an arcadeitalia member called Consoleman.

The motherboard was missing completely the sound and didn’t sync with the monitor.

After checking with my sound probe that the sound was really missing by probing the pre amps, I started to check the Z80 which was confirmed good and RAM which was faulty.

Changing the ram restored the sound completely.

The Sync problem was not easy to check because the TTL which outputs the signal to the finger board is under the romboard.

In anycase I managed to test it from the solder side and I noticed the composite signal was about 14khz, that is why was not syncing.

I proceeded to desolder it

and tested out of circuit with my programmer as good….

Instead of soldering the same part, I decided to find another 74Ls125 among my junk boards.

It was not common but in the end I found it on another board and soldered it.

Motherboard was 100% fixed.

Probably my programmer hadn’t enough sensibility to declare the part as bad. First time it happens.

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