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mypinballs

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Hi,

Back with another old taito board and an idea to see if I can convert it in to something better and more fun. Nothing against Kageki, but its not my cup of tea!

I thought I'd have a go at trying to convert to Insector X as it looks more like the thing I'd enjoy and its another 3 x z80 version of the pcb.

A caveat is this may or may not work out, so its just experimentation and trial and error for fun, like my other 2 Taito football pcb experiments were previously.

So I have this board

fullsizeoutput_e05.jpeg


From some investigation, mame research, rom ident tools and pics off jammarcade.net I have worked out the following:

U32 & U31 are the main game roms both 27c512 roms (64k each)
U38 is the sub cpu rom (27c512)
U1 to U8 are Graphics roms (1mbit mask roms)

So looking at Inspector X the main game rom is a 27c1001 and the sub rom is a 64k. I thought I'd try an experiment and split the main insector x game into 2 files, swap the sub rom like for like and see what happens. Also kept all 4 pals the same.

This is the board with the new roms in

IMG_8710.JPG


On powering up I got this:

IMG_8711.JPG


Not a total disaster, but not sure what I've missed in terms of a 'coin error'.

The font issue I am not too worried about currently as I am doing what I've done before with the other boards and only altering the game rom parts to start with and using the old graphics roms in place. An interesting note also is I can get the picture above to flip with the correct dip switch settings from the manual for insector x, so the game code must be running. To some degree anyway.

So if anyone has any thoughts I'd love to hear what you think etc. I have tried a simple addition to the gamma harness and some 120R resistors to 5v on the coin counter outputs but does nothing.
 
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twistedsymphony

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I've looked over this hardware for conversions a bunch of times. it's been a while but I seem to recall nearly every game that was plausible ended up having some customization that made it not super viable. So for instance Arkanoid Revenge of Doh looks promising for a couple of other games but the IO is missing a bunch of stuff since it's streamlined for spinners.

peeking at MAME for Kageki to Insector-X it looks like the biggest hang up will likely be on the Audio side of things. as it looks like their audio CPUs are configured differently.

looking at the ROM mapping I'm seeing this:
b97__03.u32 should be divided in half ->
lower = b35-13.bin
upper = b35-10.9c

b97__07.u38 -> b35-14.bin

b97__01.u1 divided into 1/4ths ->
b35__01.13a
b35__02.12a
b35__03.10a
b35__04.8a

b97__02.u2 divided into 1/4ths ->
b35__05.7a
b35__06.5a
b35__07.4a
b35__08.2a

personally I'd test this out in MAME first and if then burn at least the main CPU and Sub ROM
 

mypinballs

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I've looked over this hardware for conversions a bunch of times. it's been a while but I seem to recall nearly every game that was plausible ended up having some customization that made it not super viable. So for instance Arkanoid Revenge of Doh looks promising for a couple of other games but the IO is missing a bunch of stuff since it's streamlined for spinners.

peeking at MAME for Kageki to Insector-X it looks like the biggest hang up will likely be on the Audio side of things. as it looks like their audio CPUs are configured differently.

looking at the ROM mapping I'm seeing this:
b97__03.u32 should be divided in half ->
lower = b35-13.bin
upper = b35-10.9c

b97__07.u38 -> b35-14.bin

b97__01.u1 divided into 1/4ths ->
b35__01.13a
b35__02.12a
b35__03.10a
b35__04.8a

b97__02.u2 divided into 1/4ths ->
b35__05.7a
b35__06.5a
b35__07.4a
b35__08.2a

personally I'd test this out in MAME first and if then burn at least the main CPU and Sub ROM
Thanks for the reply. Yes maybe this won’t be possible but worth some real hardware testing I think like the other projects. Nothing to lose really with some rom change tests. The images I posted above are the results of doing the game rom split and sub rom swap as I detailed

Yep I already split the graphics roms in preparation

I was wondering about this ‘coin error’ message and what it’s complaining about. Maybe some io issue

a mame test with the files I’ve created will be interesting to
 

mypinballs

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quick update. Some good progress made. Got passed the coin error issue and the game will now run. Plenty of things learnt about the I/O custom chip (SETA X1-004) and what the 'coin error' means. More info on this later on what I've learnt. This hardware is really quite interesting with the variations and what taito did between versions. You really can't beat some real hardware logic probe testing & tracing. But first some screenshots of the game running

Taito Logo screen
IMG_8760.JPG


Insector X welcome screen in attract

IMG_8761.JPG


Main attract game play

IMG_8764.JPG


Video here of the attract mode and me playing a quick game (badly with 1 hand!)

https://www.instagram.com/p/CLpZvkZn3CB/?utm_source=ig_web_copy_link

Now onto the graphics rom changes
 

mypinballs

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So some info on the I/O side of things. Handled by the custom SETA X1-004 chip. I started by looking at some of the pics of the original Insector X Boards and the additional factory green wires. From looking a this it shows some wires added to pins 18-21 of the X1-004 chip.

I then had a look in Mame, which I found some info on the 8bit port for coin handling and other system type switches like service and tilt. I realised that this chip must read various 8 bit ports and therefore I wondered if the config between kegaki and insector x was different. Comparing the 2 I found that the 2 coin switch inputs are moved on insector x as shown below on my table in the attached image. When looking at the kegaki board, pins 22 and 23 are grounded so this made me realise the 'coin error' message is about checking for stuck closed switches on boot up.

IMG_8768.JPG


Therefore by unsoldering the pins of the X1-004 ic at 22 & 23 and then adding jumper wires to pins 20 & 21 respectively I was able to move the coin inputs to the correct place for insector x and avoid the stuck closed ground problems shown earlier.

IMG_8778.JPG


This is just temporary and I will most likely desolder the chip, socket it and have pins 22&23 outside of the socket with the jumpers.

Note about pins 21-18 and the 4 green wires: By moving the coin 1 & coin 2 inputs up on insector x the remaining pins 21-18 are left for coin meters and coin lockout. This is what the 4 additional wires route to in my view. The chip they route to is a darlington transistor array.
 

twistedsymphony

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Nice Work!

This is something you could also patch in the game binaries... stuff like coin inputs are usually only collected once per loop so it might not be too bad to patch.

generally I like to run 100% original code but depending on how easily (or not easily) reversible the PCB mods are it might make more sense to do it as a software patch rather than a hardware patch.
 

mypinballs

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A note about the graphics roms. After looking at the kegaki board and tracing various data bus pins to the SETA X1-002A chip I was able to determine this custom chip has a 32bit data bus and therefore the way to slice up the insector x graphics roms to fit into the kegaki board is not a straight forward divide by 4 for each.

First the files needed to be split in half then each of those needed to be bytewise split.

So the 8 graphics roms are in 2 sets of 32bit data. ie U1,U3,U5,U7 is the low address and U2,U4,U6,U8 is the high address

IMG_8779.JPG


I am waiting for some 27c1000 ics to try this out on the real hardware, but some mame tests showed the correct sprites, though some palette info was wrong which I need to see if thats just mame config stuff or something else. Real hardware is always best testing wise. Pleased with progress though

IMG_8769.JPG


fullsizeoutput_e09.jpeg
 

mypinballs

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Nice Work!

This is something you could also patch in the game binaries... stuff like coin inputs are usually only collected once per loop so it might not be too bad to patch.

generally I like to run 100% original code but depending on how easily (or not easily) reversible the PCB mods are it might make more sense to do it as a software patch rather than a hardware patch.

Yes that is an interesting point, something to look at later maybe. Understanding the hardware design is part of the fun of this, but having simpler solutions may be better in the long run. The SETA chips are pretty handy.
 

twistedsymphony

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Nice catch on the 32bit graphics. This arrangement is not captured in MAME, the driver treats them like individual 8-bit ROMs.

I'm honestly surprised hardware this old uses 32bit graphics data. Then again I do often see graphics data like this where the first 8-bits are used for the sprite, the next 8-bits are used for the mask, then the next are pallet, and so on... so it could be they're still out of order if you're getting the pallet data incorrect.

Is the audio working on this? it doesn't look like there are any audio ROMs on Insector X so I'm guessing it's all built into the program ROM space.
 

mypinballs

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Nice catch on the 32bit graphics. This arrangement is not captured in MAME, the driver treats them like individual 8-bit ROMs.

I'm honestly surprised hardware this old uses 32bit graphics data. Then again I do often see graphics data like this where the first 8-bits are used for the sprite, the next 8-bits are used for the mask, then the next are pallet, and so on... so it could be they're still out of order if you're getting the pallet data incorrect.

Is the audio working on this? it doesn't look like there are any audio ROMs on Insector X so I'm guessing it's all built into the program ROM space.

Yeah I'm wondering if I still have it out of order, it took an age to fathom out what I got above already! It makes more sense once you investigate the SETA chip. Interestingly the SETA chips were used on later hardware aswell I think, though I've not investigated that much.

The audio side of things is next on the list, but my board had an audio fault to begin with, so I'm waiting on some new ics inc the amp to see whats up. Doing a cap change on it to.

I spent some time probing the Yamaha chips yesterday and can see the YM2203C chip select pulse in time with coin up, game start and play etc. So that is promising. The sound/music works ok in mame, but I don't think thats a guarantee. What I've seen so far is both boards use the YM2203 music chip and YM3014 Dac so I'm hopeful. The extra rom on the kegaki board seems to be for 'samples' like additional speech etc, so it has the std stuff and then this extra sample stuff to.
 

mypinballs

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Sound working! Fixed my boards hardware issue with a new amp ic.

https://www.instagram.com/p/CL1mw61nkkg

So still some investigations to do and currently tracing out how the sound section works as there might be some adjustments to do still. The sound effects are quite bit louder Than the music and not sure if the dac on the board is working perfectly. Some sound effects I'm not sure if they are correct. Music sounds good. From what I've seen so far the YM2203 ic has 2 output sections. First one is the 3 analogue channels which looks like the music generation then there's a separate data section that goes through the dac Y3014 and that looks like sound effects at the mo. Still have some caps to change in this section aswell.

Also this Kageki board has 2 op amps on it (rc4458 ), whereas the insector x board only has one. I'm thinking this may be because of the extra 'speech sample section' on Kageki.

Maybe there are some resistor/cap value changes to for variations on the sound sets, as with pinball sometimes the same sound board sometimes had part value changes to adjust the filters/attenuations etc.

Really want these 27c1000 roms to arrive quick smart so I can get the graphics sorted out!
 

mypinballs

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Update :) Graphics Fixed. :):) After burning a real set of roms using some 27c1000 with a small jumper hack on each one so they run the same as the original 28 pin mask ones I worked out that the rom files I had created were the wrong way round, ie the 4 roms that were created from insector x graphics rom u1 actually went in location 5-8 and u2 to locations 1-4.

MAME confirms the graphics now runs perfectly to

IMG_8878.JPG
IMG_8879.JPG
IMG_8882.JPG
Screen Shot 2021-03-07 at 22.44.23.png
Screen Shot 2021-03-07 at 22.45.13.png



Interesting spelling of 'Cancel' aswell ;)

we also now know what happens if you swap the 2 graphics roms around in an original insector x PCB to 😝
 
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twistedsymphony

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nice work. though I'm confused what your jumper is doing... is that just to transfer Vcc to pin 32? any reason you would just jump pin 32, 31, and 30 together on the bottom of the PCB?
 

mypinballs

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nice work. though I'm confused what your jumper is doing... is that just to transfer Vcc to pin 32? any reason you would just jump pin 32, 31, and 30 together on the bottom of the PCB?

The masked roms used for the graphics are 28 pin ones - TC531000 and are 1mbit devices. You can't get eproms that are this big in a 28 pin package annoyingly, so the best option is to use a 27c1000 eprom as its the same pin layout, but you need to jumper pin 32 to pin 30 as the top 4 pins stick out of the sockets.

TC531000

IMG_8886.JPG


27c1000

IMG_8885.JPG
 
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