Why would arcade picture flip 180 degrees?

[diverdown]

I bought an upright 2 player cab with a street fighter Jamma board.  This is i believe wired backwards with buttons 123  above 456 etc....... but I digress.

I just bought a NEO GEO MVS1 pcb and Metal Slug 4 cart.......  it is JAMMA and I swapped out the street fighter board and turned it on.  It all worked fine except the image is upside down....... Why would this be  and can it be fixed short of rotating the monitor?


rotating the 29' is not a real problem but it makes it anoying to swap games over

[grantspain]

should have a screen flip option on the dil switches or set up menu

[diverdown]

ta,   I had a quick look but mvs carts are new to me....... may have a look  in mame 1st to see wher it is...ta


[EDIT]  I just had a look in mame and there is no flip screen option for metal slug series.   I have had a look on actual game and menue items are the same.  There are 10 hard dips on MVS PCB but i dont know what they do, apart from 1st which enters test/setup mode


any more ideas?

[rockin_rick]

Is the monitor mounted upside down, and the SF board had it's output flipped?

I checked the service manual for the mvs found at KLOV - neo geo mvs and it didn't show any of those 10 hard dips as screen flip, nor any other mention of screen flipping.

I doubt that it would be the cart, unless there were special carts that had flipped video output for some reason (that I've never heard of, but also never checked into).  Is it a USA mobo/cart?  (don't know if that even matters).

Rick

[diverdown]

RR  This is where i went last night - I couldnt find any Dip settings to flip the monitor, on the SF2 PCB there would be,   So yes It was probably th monitor was upside down.  Given that the bloke I bought it from had the buttons upside down it would fit that he had the monitor that way too.

I flipped it around to suit NEO GEO MVS and will then change other PCBs if they dont work.


Problem solved everyone so to

and in case any one get here from a thread search the NEO GEO DIP switch settings that are of any use I have found are

1 - Test mode
8 - Free play

Basically if you flip 1 and enter the test menu then go to the hard dip  settings then you can see on the screen what they are for. If you flip the dip switch it will change on the screen and you can see it's effect.

[johnnya]

http://www.crazykong.com/dips/NeoGeo.txt