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Building a development cart for the Neo Geo is quite easy because you only need to desolder the mask roms and replace them with eproms.
Not any board set is suitable for it because SNK added encryption chips to the later revisions. More info here: https://wiki.neogeodev.org/index.php?title=Category:Cartridge_boards
The eproms can be programmed with a regular eprom programmer which supports 42 pins and the given eprom type (my programmer is a WELLON VP 280B).

The following eproms I am using:

1 MB rom files - M27C800 (ST)
2 MB rom files - M27C160 (ST)
S1 rom - M27C1000 (ST)
M1 rom - M27C1001 (ST)

Here are pics of the boards I am currently using to test my code on the real hardware:

AES boards - NEO-AEG PROGGS / NEO-AEG CHA42G-4 (Samurai Shodown 1)
AES-dev-cart.jpg

MVS boards - NEO-MVS PROGGSC / NEO MVS CHA42G-3B (Samurai Shodown 1)
MVS-dev-cart.JPG

For an easy swap you should solder sockets to the boards like this one:

eprom-socket.jpg

But if you use sockets the boards will NOT FIT into the plastic shells anymore, therefore you better should use "pin-receptacles" instead of sockets to reduce the height of the eproms.
These pins are quite expensive (0,17 EUR each if you buy 500 in a bulk) and you will need a lot of them. But it is worth it in my opinion because now you can put the boards into the
plastic shells without any bending or squeezing. The pins are from "Mill-Max" Part No: 0548-0-15-01-11-27-10-0.
This is how it looks:

pin-receptacles-1.jpg

pin-receptacles-2.jpg

pin-receptacles-3.jpg

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Yummy, nice photos and infos.

3

Hello

Very good sound neohomebrew !

thanks !

i have some questions :

i see for 32 pins : the chip is ST M27C1000
but for the 42 pins can you give me a reference ?

last question :
Did you know a list of games which each title show the reference board for aes and mvs ?

How size can you put on samurai shodown ?
and What the card get the best size on neogeo aes and / or mvs.

Not ng dev team cause i don't find this schema on the market.

thanks for all
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4

Nice.

If you swap chips often, ZIF sockets are really nice and avoid the risk of bending/breaking pins:
https://en.wikipedia.org/wiki/Zero_insertion_force

Sure, they're expensive. But nothing on the Neo Geo is cheap wink
avatarZeroblog

« Tout homme porte sur l'épaule gauche un singe et, sur l'épaule droite, un perroquet. » — Jean Cocteau
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5

pckid (./3) :

i have some questions :

i see for 32 pins : the chip is ST M27C1000
but for the 42 pins can you give me a reference ?

The chips for P, C and V roms have 42 pins (M27C800 = 1 MB, M27C160 = 2 MB)
The chips for M1 ( M27C1001) and for S1 ( M27C1000) have 32 pins.
pckid (./3) :
Did you know a list of games which each title show the reference board for aes and mvs ?
For AES boards: http://www.arcade-collector.com/search-neogeo-board-prog42g (check the right menu boxes for other PROG Boards / CHA Boards)
For MVS boards: http://mvs-scans.com/index.php/Main_Page or https://wiki.neogeodev.org/index.php?title=Category:Cartridge_boards
pckid (./3) :
How size can you put on samurai shodown ?
I think the maximum would be: P roms - 1MB + 512k, C roms - 8 x 2 MB, V roms - 3 x 2MB
pckid (./3) :
What the card get the best size on neogeo aes and / or mvs.

The combination with the most rom space is PROGBK1 (https://wiki.neogeodev.org/index.php?title=PROGBK1) + CHA512Y (https://wiki.neogeodev.org/index.php?title=CHA512Y)

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thanks very much !

it's great post .
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7

You're lucky these are not metallized holes and all traces connect to the eproms on the solder side.