Nintendo VS EPROM Speed Critical?

bstnguy

Well-known member
Joined
Jan 30, 2008
Messages
1,812
Reaction score
36
Location
Boston, Massachusetts
Got a set of ROM images from WickedBass and nuttin' in my VS cab.

The ROMs verified, but one of them is a different speed. 5 of the 6 are 300nS, and one of them is 450nS.

Is the speed that critical?

Thanks
 
It can be. It all depends on what the EPROM is used for and the speed of the circuit it's used in. I know that would be the second thing I'd check. The first thing would be corrosion in the chip sockets. Those Nintendo boards are bad about that.
 
Thanks for the info.

The board runs a VS Hogan's Alley chipset fine, so I know it's not the board or the sockets.

The EPROMs all verify correct in the burner, but that's not checking speed.

I'll try a faster EPROM and see what happens.

The other item is it might be a bad ROM dump too....
 
Thanks for the info.

The board runs a VS Hogan's Alley chipset fine, so I know it's not the board or the sockets.

The EPROMs all verify correct in the burner, but that's not checking speed.

I'll try a faster EPROM and see what happens.

The other item is it might be a bad ROM dump too....

Feed the checksums through ROMIDENT or through Google to see if they come up matching to what's known in the MAME dumps.
 
Which position is it? If it is the graphics part, you should at least get something up on the screen.

Also, since you stated this was Vs. SMB in your other post, SMB has certain requirements other games don't. If by itself it has to be in a certain position and requires a RP2A04 or a small mod to the board.
 
2600 wins!!!!!

Bstnguy loses. Crap. Didn't know it was a different microprocessor.

I'll hunt one down and start over.

Thanks!
 
Woops, left out some detail. The RP2A04 goes on the other side of the Vs. Board where the other 2A03 would go. The side with all the VS. SMB chips still uses the RP2A03 as the main procesor.

I highly suggest taking a look at the manual. The 2A04 isn't worth tracking down and I'd just ask how to do the jumper mod.
 
Ug.

This wasn't as easy as I thought.

But thanks for keeping me from chasing my tail for the next month! LOL!!!

I'll hunt down a manual and read up.

:)
 
Okay, now, is there a hack to use an RP2A03 in place of the RP2A04?
You could put another game on there, but the 2A03 isn't going to do anything by itself.

What you want is to get a piece of wire and jam into 2 spots in the 2A03 socket(You can do it a nicer way of course). Do a search by Raven or Phet and it will show you the picture as I forget the pin numbers off hand.
 
I'm running a VS Unisystem w/ a Hogan's Alley MPU (already changed out the Gun for a standard CP)

I'll look up the Raven or Phet mod.

Thanks!
 
Update:
ROMIdent all ROMs, and they are correct.

Did the Phet mod by jumpering J2 pins 30-38.

RP2A03 is in J8, RP2C04-0004 is in F8, ROMs are in 6a, 6B, 6C, 6D, 8A 8B.

Think I followed the Vs. SMB Manual correctly.

Board is an MDS-05-CPU and is verified workign with a Hogan's Alley chipset.

All I get is a gray screen.

AAAHHH!!!!
 
DONE!!! Phet mod popped out on one side.

Here's the final set up:

Phet mod by jumpering 2J pins 30-38.

RP2A03 is in 8J, RP2C04-0004 is in 8F, ROMs are in 6a, 6B, 6C, 6D, 8A 8B.

Board is an MDS-05-CPU and is verified working with a Hogan's Alley chipset.

Success!!!!!

Thanks for th help gang!
 
Last edited:
Back
Top Bottom