Toaplan Zero Wing rom chips

[SquidDude]

Hi, I'm working on a Zero Wing board atm, and I need to replace on of the sprite rom chips (it's pretty rusty looking underneath, and as I took it out of the socket to reseat it, a couple of the legs snapped clean in half)



It's branded 15-F1, I've tried searching for that and 8921 E (even though I don't think that's the model of the chip), and I've found absolutely 0 info or even reference to it.
I've also checked what chips are used for sprite storage on other comtemporary toaplan boards, Truxton seems to use 32 pin chips (this Sharp 15-f1 is 28 pin), Outzone seems to use custom (or at least toaplan branded) chips, but Hellfire might use the same chips as Zero Wing?

Truxton:

Outzone:

Hellfire:

(images from jammarcade.net)

Can anyone help shed some light on this chip? If I can find out some info on the pinout, then maybe I can at least try and dump the rest of the chips on my board to see if they're dead.
Thanks!

 

[TheDaddy]

What is on the chip label lifted ?? These are the roms for this board :-



Assume its a standard 1024 looking at that, Thats if I am reading what you are asking correctly.

This is the MAME cpp and can help as well :-

mame/src/mame/toaplan/toaplan1.cpp at master · mamedev/mame

MAME. Contribute to mamedev/mame development by creating an account on GitHub.

github.com

Dave.

 

[SquidDude]

What is on the chip label lifted ??

"o15 04"

Thanks for the info, seems like it is one of those "1024" chips. Sorry to be a pain (this is all new to me), but could you give me an example model number of a 1024 chip? Been searching about them but haven't found much, and I just want to be 100% sure that I pick the right type of chip on my reader so I don't kill anything lol

 

[TheDaddy]

Ok , I can give you the info no worries but sometimes its better to google and research a bit yourself as it will help you in the future. So the rom file you need is :-



And the rom is something like a 27C101

Dave.

P.S you wont kill anything with incorrect roms , Just wont work correct. Sometimes they can be a nightmare to select and program them especially when you get to 27C400 , 27C160 et ect ect !

P.P.S I need to get back to repairing ! Cant get motivated at all. Cant seem to repair anything when I am in there.

 

[SquidDude]

Thanks, after finding out the size of the chip's memory and googling with that, I'm getting some info on it.

Seems like I may be dealing with a similiar chip to one of these, and apparently they're really hard to find replacements for.

But it does seem like there's some good reproductions/adapters out there, so that'll probably be the route to go down if I can confirm that these are dead (sadly my programmer doesn't seem to be able to read them).
I think my best option for now might just be to solder some component legs to the chip to replace the broken pins haha
Thanks again for the help!

 

[TheDaddy]

27C101 is 128k x 8.

Dave.

 

[sukhbir]

Eprom you require is a 128kb type .
they usually come as 32 pin package,but they can be used to replace a 28 pin maskrom .
From memory if your maskrom is non jedec then you will have to swap 2 pins which are pin 2(a16) with pin 24(OE).
Once programmed you need to overhang pins 1,2,32,31 in the socket.

 

[caius]

You can replace 28 PIN 1Mbit (128x8-bit) MASK ROM with 27C1000 (or other compatible NON-JEDEC 32 pin 1Mbit EPROMs like 27C301, 27C100, etc) with following mods .

• Connect pins #30, 31, 32 together and connect them to pin #1 with a small wire.
• Connect pin #2 to pin #16 with a small wire.

You can use also JEDEC EPROMs like 27C010 but they require more mods.

If you want a neat job I designed an adapter to use TSOP32 FLASH ROM on 28 PIN carrier board :

28 pin 1Mbit Mask ROM replacement by Caius Arcade Repairs & Engineering on Tindie

Replacement of 28 pin 1Mbit Mask ROMs used on arcade PCBs

www.tindie.com

 

[safaex]

Hello! I'd like to make follow up question to this. I'm trying to fix a Rally Bike by toaplan. It had rom 6, 7 and 8 testing non working, all 28 pin 1mbit masked roms. I saw that the board supports 32 pin sockets in those places so I swapped them out and fitted 010 roms. No difference, still missing a lot of graphics. So I tried to short the pins together and changing the roms to 27c1000 as Caius described above. Now its a garbled mess of all kinds of graphics but still plays.

So I'm thinking I made a small oopsie. Maybe I was not supposed to swap the sockets as now the extra 4 pins on each rom that are shorted to other pins also are shorted on other places on the board as they are still connected through the socket. Was I supposed to keep the old 28 pins sockets but just shorting the pins as described, leaving the 4 extra pins floating? Also to support my theory, putting back original rom 9 doesn't change anything even if it is working. It made some differences to text and title screen before shorting the pins.

I will try my hypothesis but for the sake of documentation thought it was good to make a post.

 

[safaex]

So I removed all my jumpering on the solder side and applied them topside to the eprom itself and now the game works 100%. It was pin 1 and 2 that can't be connected to the board, so cut the pins and put a little electric tape in the socket.