Hanaho Multi-Taito PAS BIOS downgrade for 20-in-1 (and audio repair log)

DogP

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Hanaho Multi-Taito PAS BIOS downgrade for 20-in-1 (and audio repair log)

Hey,

A fellow KLOVer asked me to look into downgrading his Paradise Arcade Shop Multi-Taito to the old BIOS, so it could run the original Taito 20 game image (as well as the Taito 10 and SNK), rather than being limited to the 10 game image and the buggy 20 game image. I had dumped the TSOP flash BIOS on my original Multi-Taito a couple years ago... so I figured if the boards are identical, it should just be a matter of pulling the flash chip and manually burning the old BIOS. I did that, and I just wanted to confirm that yes, it does work.

Of course unfortunately, this downgrade requires desoldering the small flash chip, using a TSOP adapter to reburn the chip, and resoldering it... so it's not exactly an easy fix, but it does work. Just a few notes...

First, the flash chip is actually different between the original and PAS versions. The original boards have a TE28F800 (8mbit) chip, the PAS boards have a TE28F160 (16mbit) chip. I'm not sure if it's necessary, but I doubled the original chip image and burned it to the new chip.

Because of the size and chip difference, I was afraid the old code would detect a different chip and barf... either just trying to use it (the code reads the flash chip type), or when attempting to reflash it (when switching between 10/20 Taito and SNK). But nope... I popped the card in and it immediately worked, and switching to another version, it simply erased and reflashed the chip successfully. So now the PAS board seems to function identically to the original, and like the original boards, rejects the PAS image.

In addition to the flash chip difference, there are also a few other cosmetic differences I noticed between the boards (appears to be common across the 3 or so of each board I've seen). The original boards have a code of 0534 silkscreened on the board next to the flash, the PAS boards have 0543. The Xilinx CPLD has "HH V1.00" laser engraved on two lines on the original, and all on one line on the PAS. The laser engraved 'P' on the flash chip is smaller and further from the edge on the original than the PAS, which has it above the 'F' of "FLASH". I also don't think the PAS board ever had the "HANAHO VOID IF REMOVED" sticker over the SD card. None of these are functional differences, but figured I'd note them in case you were trying to ID a board.

One thing to note... I don't think the PAS BIOS itself is faulty... it looks like the game emulation code that they built for the PAS image is faulty, but the game image and BIOS have to match up. And unfortunately, it doesn't look like there's an easy way to make the upgrade happen over the SD card (I believe others have tried, I didn't... I just went brute force at it with a soldering iron as I was unsure whether it was going to work at all). It seems that the old and new BIOSes detect something is incorrect with the other image and don't allow it to reflash across original/PAS versions.


_____Repair_____

He also had an original Multi-Taito board that worked, but had no sound that he asked me to look at. I tracked it down to two problems... first, it had a bad DAC (I could see serial data going in, but nothing coming out). This is U2, a CS4334-KSZ 8-pin SOP chip just off to the side of the CPU.

I also noticed that if I injected a signal into the amp, I got no sound... so I figured the amp was dead as well. This is U1, an LM4871 8-pin leadless (with exposed ground pad) WSON chip near the corner by the "JAMMA" text. This part has the no accessible solder joints, so it must be desoldered and resoldered using hot air. There are other suitable replacements as well, such as the LM4991.

Luckily, both of these parts are readily available from Digikey, Mouser, etc. I ordered and replaced them... and the board is back up and running. Both of these parts run directly from the cabinet 5V, while basically everything else is behind voltage regulators... so I'm guessing the cabinet had a faulty power supply and damaged these parts.


Anyway, attached is a zip with the original V1.05 BIOS (to downgrade the PAS BIOS), as well as a pic of the bad audio parts that were replaced. Hopefully some of this info helps someone in the future.

DogP
 

Attachments

  • taito_v105.zip
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  • repair.jpg
    repair.jpg
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This is a long standing issue with the PAS boards that goes back many years. I remember getting hold of one of these and trying to run the 20 images. For a while there was talk about getting the programmers to come up with a solution, but nothing happened. I ended up sending my board back and I eventually found a suitable board on eBay.

I want to thank you for taking the time to figure it out and share the info.

Great work....
 
Yeah, there may be a way to trick it into burning the other BIOS from an SD card, but as it was, I only had one board... and the time to pull the chip and reburn it was likely much less than reverse engineering the BIOS update procedure (and more likely to work).

That's too bad that the programmers couldn't/wouldn't do it though, as I'm sure it'd be much easier to make a workaround if you have the source code.

DogP
 
Yep... it's attached. It wouldn't zip small enough, so I 7zip'd it... but had to rename it .zip for the forum to allow it to attach. So, rename the zip to .7z and open it with 7zip.

DogP
 

Attachments

  • PAS_taito.zip
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