Home Page Forums MAME MAME TMS-09xx/1xxx thread (was New Dumps)

A lot of the glob ones don't tell you anything when you decap them either unfortunately, especially once we're into later 80s / 90s tech. I think 'mask ROM with visible bits' is the least common of the techs.

I fear a lot of these are going to require much more advanced techniques (microprobing / microbonding to read out ROM arrays directly etc.)

I only played Monkey Kingdom and it was long long time ago, never owned it only played on a friend's unit. It's very likely they use the exact same ROM as you say though, but they will still need to be dumped I guess so we can prove it.

Yeah that's true, the Gakken games seem to fall under this category unfortunately, Gakken Soccer was one of my favorite LCD games when I was a kid, but after decapping it shows no visible bits.

I don't know the exact process, but don't you sometimes also have to remove a layer (or two) of the die to see the bits sometimes? Or are there cases will that still doesn't reveal them?

unless it's a mask part it's not going to reveal them, even then some of them are especially difficult.

mask ROMs are basically 'set in stone' as it's part of the manufacturing process, it's more expensive, you typically have to make them in batches, once made they can't be changed, it's basically an array of fuses inside the chip. we can only see them optically *because* they're set in stone like this, the bits are physical.

for any part using regular erasable / programmable tech (or even on later 00s ones, flash tech) the bits are not visible, they're never going to be visible, they're electrical charges, not something you can see. all you do by decapping them is permanently render them unusable, with a die shot for future reference.

for smaller production runs it's cheaper (and lower risk) for a manufacturer to produce a huge batch of reprogrammable chips / dies then program them as needed than it is to produce batches of mask ROMs (which typically would have had a larger minimum order quantity) so once MCUs of that nature were an option, the majority used them as it made more financial sense than committing to a batch of mask ROM based MCUs.

even for non-glob MCUs found on arcade boards etc., the mask type is much less common.and again typically only found on earlier productions.

as I said, some of the most recent ones (from the last 5-10 years) even used flash tech, some of them are 100mhz+ ARM processors and 8meg of ROM under a tiny glob even if they're driving non-video, simply because that's what became the cheapest option (somebody I know worked on one about 10 years, and was amused by what a waste of tech and processing power it was)

It is the same as the ebay auction I am pretty sure; unfortunately I no longer have the boards. I bought them in the early 90's (90-91 era most likely) from all electronics. I still have the ULN2804's and 14 segment displays but the rest is long gone. I powered one up and it indeed played like an electronic scrabble game. You got your set of letters and had to form words, and it would score. Of course it couldn't check the "quality" (or lack thereof) of your words and would just score the letters you used.

@Rik: Since kevtris is around maybe you could arrange sending him that select-a-game pac-man cart for dumping? I'm eagerly waiting to have that system fully preserved

Heh, yeah, I have a whole box of games to send him...
Guess I'll get that on it's way soon.

Was hoping to find the one remaining cartridge, or did someone else get it already? Basketball I think...

I'd still like to see the NES-on-a-Chip Intellivision Plug and Play ROM that Kevtris apparently dumped some years ago so that we can add it to MAME...

I'd like to see that Famiclone Intellivision myself.