What's new

Apocalypse

Staff member
Legendary
Joined
Dec 6, 2017
Messages
3,656
Reaction score
6,251
Location
New-Zealand
Does anyone have a valid dump of IC33, Sega ref. 315-5654?
It's missing on the board I have here.

What is the behaviour of the board when pulled? I only get a black screen.
 

Apocalypse

Staff member
Legendary
Joined
Dec 6, 2017
Messages
3,656
Reaction score
6,251
Location
New-Zealand
Hey,

I know MegaPlay isn't that common but surely there must be a member here who can answer my second question at least.

:)
 

caius

Grand Master
Joined
Nov 21, 2016
Messages
553
Reaction score
792
Location
Italy
Sadly the dump we have on JAMMArcade is not working because the device is combinatorial but has latches inside and the original dumper didn't know this.Therefore it must be manually reversed.If someone can provide us the chip we can try to reverse it.
 

Apocalypse

Staff member
Legendary
Joined
Dec 6, 2017
Messages
3,656
Reaction score
6,251
Location
New-Zealand
@Hammy wonderful mate! Thousand thanks.
Out of curiosity, is it with a cartridge inserted or without any?
 

Hammy

Champion
Joined
Feb 3, 2018
Messages
1,034
Reaction score
1,895
Location
U.K
I'll dig it out again later! Hell maybe i'll finally get around to testing that mod bios now the blank carts are in :P
To be totally honest with ya, when i got it working it was in the cabinet for about 1 week and then boxed on the shelf as i know for a fact it's gonna go bad again.
 

Hammy

Champion
Joined
Feb 3, 2018
Messages
1,034
Reaction score
1,895
Location
U.K
Without game you don't get the "licence" screen and it goes to the classic cart not used screen as normal.
 

Apocalypse

Staff member
Legendary
Joined
Dec 6, 2017
Messages
3,656
Reaction score
6,251
Location
New-Zealand
Thnaks again Hammy!

I really don't undestand what's happening with that motherboard. I get a black screen whatever I do (with the missing IC33).
I found the Z80 is in a permanent interrupt (INT pin low) coming directly from the VDP.
VDP is fine (swapped with one from a MS).
No broken lines found whatsoever.
What's even weirder is if I burn a MS test ROM in place of the BIOS it does work fine so I know at least the MS part of my MegaPlay motherboard used for cart detection and additional overlay works.
 

Hammy

Champion
Joined
Feb 3, 2018
Messages
1,034
Reaction score
1,895
Location
U.K
I have one here in for repair that does boot but works as if the GAL is dead! (won't load game but TMSS starts)

The licence screen is a sign of the <megadrive> VDP fire up maybe that's toast?
 

Apocalypse

Staff member
Legendary
Joined
Dec 6, 2017
Messages
3,656
Reaction score
6,251
Location
New-Zealand
I have one here in for repair that does boot but works as if the GAL is dead! (won't load game but TMSS starts)

The licence screen is a sign of the <megadrive> VDP fire up maybe that's toast?
Already replaced the MD VDP.
 

Apocalypse

Staff member
Legendary
Joined
Dec 6, 2017
Messages
3,656
Reaction score
6,251
Location
New-Zealand
Up.

Am I the only one on earth caring to dump those Sega PLDs?
 
Top