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Why is The Immortal such a pain in the ass?

Why is The Immortal such a pain in the ass?
by on (#26994)
This question was brought up on another forum and it has me quite curious.

This game seems to consistently have major graphical issues seemingly caused just by the cart connection. To elaborate, the game program is running fine but the graphics are messed up, but not in the dirty connection way with garbled tiles and/or lines. Instead, the picture seems to be formed just fine, but the screen shakes around violently. It seems as if there is a problem with the timing of the drawing. Some people have said they can correct the problem just by adjusting the cart in the NES. I can't. The ROMs must be making the connection just fine though because even in this condition, I can dump the cart and get 100% valid data.

From what others have said, it seems the majority of these carts have the exact same problem. It just uses a typical NES-TLROM-03 w/ MMC3B

If anyone would like to see the problem for themselves, I could capture a short video of the issue.

by on (#26995)
Looking at this in FCEUXD SP, it is using "the bad color" aka 0x0D as the black background. That could definitely cause the screen to shake as the TV decides it sees a sync signal. Don't know why repositioning the cart would work. Might try different TVs with the same cart/NES.

by on (#27001)
bunnyboy wrote:
Don't know why repositioning the cart would work.

Unless there's an issue with sprite 0 that shows up only during the sprite-pattern-fetch phase of the scanline.

by on (#27004)
Maybe why it shakes so much is that in addition to using low-voltage color $0D, it also uses all the color deemphasis bits to make the screen darker, lowering $0D's voltage to 1.043 volts, 0.243 relative to sync according to this thread. The Immortal also uses $1D in the title screen for the wizard's black, which with all the bits set, could also potentially cause problems, since it's voltage is only slightly more than $0D with no bits set (and that already causes problems with Game Genie). I guess Electronic Arts didn't really care because it was 1990, and I guess most TVs during that time were able to output the low levels properly. Out of curiosity, how old is the TV you used, BootGod?

About Sprite 0, tepples, are you suggesting that The Immortal uses sprite 0 hit? Having personally finished the game, I don't think it uses sprite 0 hit or even any split-screen effects (the IRQ is just an RTI instruction). Since it doesn't use sprite 0, how else could sprite 0 or the processes for sprite 0 hit mess up the game?

by on (#27005)
strangenesfreak wrote:
... and I guess most TVs during that time were able to output the low levels properly. ...


I have actually seen more problems with recent LCD tvs instead of CRT ones. This is only based on a sample of ~8, but the LCDs may be trying to do more strict voltage levels.

The 0D + emphasis may be the full reason why Immortal is especially bad.

by on (#27010)
strangenesfreak wrote:
About Sprite 0, tepples, are you suggesting that The Immortal uses sprite 0 hit? Having personally finished the game, I don't think it uses sprite 0 hit or even any split-screen effects (the IRQ is just an RTI instruction). Since it doesn't use sprite 0, how else could sprite 0 or the processes for sprite 0 hit mess up the game?

Wild guess, given all the topics in NESemdev about games freezing when sprite 0 logic fails.

by on (#27013)
I don't think funked up display by $0D would break sprite 0 hit even if it was in use. How the TV displays the image doesn't affect whether or not the NES detects sprite-0 hit (since that is figured out before the image is even output to the TV)

by on (#27019)
How many MMC3 games use sprite zero hit?

by on (#27020)
Dwedit wrote:
How many MMC3 games use sprite zero hit?

The only sprite 0 hit MMC3 game I've ever played so far is Gauntlet. It's used on the title screen, the scrolling text for Morak's trashtalk after those clue-finding levels, when you need to enter the password for the last 100th level (Morak is the red-hooded blue guy), and for the scrolling text in the ending. There might be more games, though.

by on (#27024)
When I used color 0x0D for Sudoku it was really shaky (unplayable) on my LCD TV. On my older CRT TV it was fine.

If you dump Immortal, can you try it on a power pak and see if the problem is ROM rather than hardware?

Al

by on (#27060)
bunnyboy wrote:
strangenesfreak wrote:
... and I guess most TVs during that time were able to output the low levels properly. ...


I have actually seen more problems with recent LCD tvs instead of CRT ones. This is only based on a sample of ~8, but the LCDs may be trying to do more strict voltage levels.

The 0D + emphasis may be the full reason why Immortal is especially bad.


Actually yes it is an LCD TV I was trying it on. I will try to hook it up to an old CRT later and see if it is any different.

by on (#27078)
Well I'll be damned, it was just the TV. I hooked it up to a CRT and it works just fine. And it must be due to the combo of using that color and it using color deemphasis bits like strangenesfreak said because my LCD doesn't have problems with other games that use 0x0D, at least in the ones mentioned, Maniac Mansion and Skate or Die 2.

Thanks for the input everyone, looks like mystery solved!

by on (#27080)
Oh yeah I almost forgot, I also remember having issues with my LCD with a couple other games, but instead of a bouncy picture, I'd get absolutely nothing at all. In fact the TV didn't seem to think it was getting a video signal at all, it was not even passing the audio thru.

The games, IIRC, were Astyanax and Snake, Rattle, & Roll.

Any ideas?
Re: Why is The Immortal such a pain in the ass?
by on (#27504)
BootGod wrote:
This question was brought up on another forum and it has me quite curious.

This game seems to consistently have major graphical issues seemingly caused just by the cart connection. To elaborate, the game program is running fine but the graphics are messed up, but not in the dirty connection way with garbled tiles and/or lines. Instead, the picture seems to be formed just fine, but the screen shakes around violently. It seems as if there is a problem with the timing of the drawing. Some people have said they can correct the problem just by adjusting the cart in the NES. I can't. The ROMs must be making the connection just fine though because even in this condition, I can dump the cart and get 100% valid data.

From what others have said, it seems the majority of these carts have the exact same problem. It just uses a typical NES-TLROM-03 w/ MMC3B

If anyone would like to see the problem for themselves, I could capture a short video of the issue.


Same like that??
Image
Image

by on (#27510)
I wonder if a game genie code would fix that. God the irony...

by on (#27523)
Yep those photos depict the problem precisely :)

by on (#27524)
Thats different from what I see on my LCD. Large black areas will restart the frame, so it looks like the picture is jumping around vertically. What is there looks fine, not fuzzy like in your pictures. Not sure what the technical reason for that fuzzyness would be.

by on (#27534)
Might it be because a (smaller) black area is restarting the scanline?

by on (#27537)
BootGod wrote:
Yep those photos depict the problem precisely :)


I have two consoles (famiclones PAL), on first game display gfx glitches, on second work correctly :)

by on (#27538)
FYI,
I get the jumping around effect when I use a Game Genie with my NES attached to my LCD TV. The same TV that glitches with other 0x0D color palette games (like Sudoku).

Al