Odd turbografx problem

I recently bought a PAL turbografx assuming it was stock but it later turned out to be RGB and region modded (one switch), as pc engine games seem easier to come by I bought a couple of those, all of which work (although in 50hz) except for one. Now this game (wonder momo) seems to have half of the background missing making it a little bit unplayable.
Here's a picture


So I was wondering if anybody knew what was causing it? Is it the region mod? is it the RGB mod? is it that the game doesn't like running in 50hz? or is the game just broken? any help would be appreciated

Edit: after looking at my own picture it looks as though the background starts halfway along the screen then continues in a band at the top of the screen

 

Not to nag or anything but does anybody have any suggestions? 'cause if I can't get an explanation I'll be taking it back as broken tomorrow

 

It could be that it doesn't like running at 50 Hz, there's no way that an RGB mod or region mod would cause something like that.

 

Maybe, I've been skeptical of the idea these are 100% compatible. Never know when a game does something odd.

 

Wait, are you not supposed to require a physical adaptor to run PCE games on a turbografx?

 

I thought I read somewhere that the one switch region mod isn't 100% compatible with everything.
I didn't think it would be the RGB mod, although I'm relatively sure that it's the bad RGB mod so I'll probably be changing that when I can be faffed
It's shame it doesn't work, the game looks pretty fun

Nope, there are a couple of different mods which allow for switching the pins which were changed in order to create the region lock
There was this one - http://www.mmmonkey.co.uk/multi-region-pc-engine-turbo-grafx-16/
and bacteria suggests the one in this PDF - http://moddedbybacteria.files.wordpress.com/2009/05/turbografx-pce-pt1.pdf

Mine is the former

 

I'm not seeing how it can be the RGB mod. As the console uses RGB internally, you'd expect a problem would be more like video artifacts.

 

I said that I don't think its the rgb mod I don't know why I carried on talking about it

 

It is definitely not the RGB mod - if it was, you would see garbage around the screen due to a timing issue. Instead, you have a clear image, but the graphics are being displayed at the wrong time.

Add to your point that this is the only game that does it out of the few you've tried, and it looks far more likely that the game simply does not work properly at 50Hz (being Japanese, it should be running at 60Hz). Obviously, the code that displays the graphics relies quite heavily on it running at the correct speed, and seeing as yours doesn't, it breaks.

The solution would be to remove the timing mod that slows it to 50Hz. Leave the RGB mod though, as that is sound.

 

He said it was a PAL unit, which means there is no timing mod.

To play this properly hes going to want to do a timing mod, not reverse it

If you are buying 60hz games, mod the unit for 60hz?

Are you the one who wanted to do this but couldnt find the oscillators? (poor memory, but I think it was?)

 

Ah, good point. I initially misunderstood 'assuming it was stock but it later turned out to be RGB and region modded' as that they bought it thinking it was a PAL machine but was actually modded that way.

BadAd is right then: you'll need to work out a way of adding a timing adjustment to the region mod - which involves adding a 21.47Mhz crystal to speed the console back up, then adding a secondary switch to switch between the two (that is, if you want to still have it run at 50Hz, otherwise just swap it entirely). (EDIT: This information came from another thread: http://www.assemblergames.com/forums/showthread.php?40783-PAL-Turbografx-60hz-mod )

Or... buy a 60Hz console to play that game. It might be a more sensible option.

 

Region modding and refresh rate are separate mods. So hes got the region mod (so using PCE games is allowed) but still running 50hz, though I can see why you may have misread/misunderstood.

I bought the last batch of the 21.47 osc's that showed up on ebay not long ago, think I have 20 of them.

If I were to do this - id probably have it all on 1 switch (using multiple throws) or go switchless. Seems pointless playing PCE games at 50hz!

 

ooh how much would you want for one?
To be honest I'd probably just whip the old crystal out, as there was never any code written for 50hz for the turbografx, doesnt seem much point in keeping it when there's only one TV in my house which doesn't accept a 60 hz signal and that's Rf only anyway