Bank Switching V rom

[pierpa86]

Hello guys,
I recently came across this bootleg where it uses 8x V Rom, the connections are not clear from the picture and I was wondering if anyone in this forum is able to explain how to bank switch between V roms.
In the photo it seems to use Ls139 already present in the card.
I see that all E0 - Chip Enable pins are connected in series, and then another wire on the LS139's Address Inputs A0a.
Can anyone explain bank switching?

Thanks in advace

 

[Burning Fight!!]

"from italia" yet you have a mercadolivre screen in portuguese leaking out of the first screenshot... hmm.

 

[skate323k137]

Can anyone explain bank switching

Not quickly lol.

Are you at all familiar with the concept in general ?

 

[pierpa86]

Hello

Not quickly lol.

Are you at all familiar with the concept in general ?

Familiar with bootleg a little, i made lootris cart, studied how the PROG and CHA board work with all detail that i can read on https://wiki.neogeodev.org/
I don't have complete mastery of eprom as it is a new subject but I have learned many things, never used a logical component LS139 / Ls74.
I have studied all kind of information that i can found about neogeo hw and sw, bootleg.
I know that for bank switching you use ls139 to arbitrate, connected to the ce pin to enable the bank.
But there are many details that I definitely don't know.
If you have some documentation that i can read or study please share with me !

Found on buyICnow.... more question in my mind
Both memory work on 3.6 volt and neogeo use 5v.
What do you suggest? adjust the voltage ? change memories and adapters ?

MXIC MX26L6420 - FOR C Rom
64M-BIT (4M x 16) CMOS MULTIPLE-TIME-PROGRAMMABLE EPROM

MXIC MX26L6420 - buyICnow.com

MXIC MX29L3211 - FOR V Rom
32M-BIT [4Mx8 or 2Mx16] CMOS SINGLE VOLTAGE PAGEMODE FLASH EEPROM

MXIC MX29L3211 - buyICnow.com

 

[pierpa86]

"from italia" yet you have a mercadolivre screen in portuguese leaking out of the first screenshot... hmm.

Yes i'm from italia, and i found this screen on the web.
Opening several bust a move bootlegs I noticed that many used 512k memories with ls139.... I have to understand why ! I hate not understanding things