NES Magician - Video Issues on an RGB modded AV Famicom

[Shou]

This is an odd one. I have an RGB modded AV Famicom and the only NES game I have video issues with is Magician. The screen is yellow at the title screen and any screen involving text is completely white. Would appreciate any insight. Did Magician use any unique NES hardware?


Check out this youtube video to see.

[Arasoi]

This game isn't compatible with the RGB PPU.

This has to do with how the RGB PPU handles color emphasis bits. On an RGB PPU they force the R/G/B values to full brightness, where on a composite PPU they add in a weaker R/G/B color and darken the luminance value of some colors.

A short list of problem games off the top of my head..

Paperboy 1/2
Just Breed
Magician
Totally Rad
Airwolf
Fantastic Adventures of Dizzy
Super Spy Hunter
Immortal

[Shou]

This game isn't compatible with the RGB PPU.

This has to do with how the RGB PPU handles color emphasis bits. On an RGB PPU they force the R/G/B values to full brightness, where on a composite PPU they add in a weaker R/G/B color and darken the luminance value of some colors.

A short list of problem games off the top of my head..

Paperboy 1/2
Just Breed
Magician
Totally Rad
Airwolf
Fantastic Adventures of Dizzy
Super Spy Hunter
Immortal

Sad to hear that I may need to get a regular unit just to play these games in composite.

Out of this list, I have Just Breed and the JP version of Totally Rad, Magic John, so will try those when I get home. Thanks for the tip! I do find it odd that the Sharp Titler PPU isn't compatible as I've never come across this bit on any Japanese site.

[Arasoi]

It seems like most of the problem games are American or European on the whole(there apparently is a larger list of Euro only NES titles that have similar problems), I have read that Just Breed's packaging has a warning about using it with a Titler but I have no confirmation.

Totally Rad's problems seem to be less major, some backgrounds being the wrong color like black instead of white/grey etc. Games like Paperboy have similar "broken but somewhat playable" type issues, like the street not being the right color and missing the grates/obstacles etc.

FWIW I run an RGB modded NES (with an additional encoder to output composite, svideo, component, and the Famicom extra sound channel mod) with a powerpak flashcart and I think the games that don't work and the minor palette issues are a small price to pay for the signal clarity.

Until one of the geniuses over at nesdev reverse engineers the PPU and create a new one it's a slightly flawed but still excellent solution for getting a nice picture from real FC/NES hardware.

[ccovell]

Totally Rad
Super Spy Hunter

These don't really cause major problems, because SSH uses the emphasis bits only when the game is paused.

Games like Magician have to be hacked in several places in order for them to stop using emphasis bits, but several other games (Felix the Cat, etc) can be fixed with 1 or 2 Game Genie (or Action Rocky) codes if you know how to do it.

[Shou]

It seems like most of the problem games are American or European on the whole(there apparently is a larger list of Euro only NES titles that have similar problems), I have read that Just Breed's packaging has a warning about using it with a Titler but I have no confirmation.

Totally Rad's problems seem to be less major, some backgrounds being the wrong color like black instead of white/grey etc. Games like Paperboy have similar "broken but somewhat playable" type issues, like the street not being the right color and missing the grates/obstacles etc.

FWIW I run an RGB modded NES (with an additional encoder to output composite, svideo, component, and the Famicom extra sound channel mod) with a powerpak flashcart and I think the games that don't work and the minor palette issues are a small price to pay for the signal clarity.

Until one of the geniuses over at nesdev reverse engineers the PPU and create a new one it's a slightly flawed but still excellent solution for getting a nice picture from real FC/NES hardware.

I tried Just Breed (didn't work) and Magic John (did work with no issues) last night. I didn't read the Just Breed manual or box but will check that.

Interesting that the Powerpak works on your RGB modded system. The Powerpak doesn't work at all for me and the maker refuses to acknowledge me on this issue. Acem77 suggested that I may need to swap out some of the chips but wasn't 100% sure on that.

Is the additional encoder just a breadboard with an RGB to NTSC converter? Is it something you can package up and sell?

[Arasoi]

Here is what I know on Magic John/Totally rad, from Moosman's page:

http://playoffline.wordpress.com/mod/rgbppu/



Comparison between composite and RGB shows the background is the wrong color.. perhaps Magic John is immune from this effect. Fully playable either way.

On the subject of getting the powerpak working in RGB yes it is required to replace one of the chips on the motherboard of the Famicom or NES. acem77 figured it out and posted his results here a while back:

http://nesdev.parodius.com/bbs/viewt...er=asc&start=0

The same fix is on my NES deck and it works like a champ, there is a poster who tried it on a Famicom and seemed to have a good result too. A good thing too because the FDS compatibility provided by the Powerpak's FPGA makes it so I can store my FDS collection and play them with ease.

The multi output on my deck is due to the RGB out being piped into a JROK 4.1 encoder board. I've seen a few of these put/modded into plastic shells so its certainly possible to do it externally, but it is initially sold as a bare pcb.

[Shou]

Thanks for all of the useful info. I'll look into replacing the chip so the Powerpak works.

It'd be great if someone created a definite list of which games use these emphasis bits. Even better if someone hacked them so we can play them in RGB.