Unhandled OpCode: Legend of Zelda - Ocarina of Time

[dx01110]

Hi,

This is my first post here at emutalk.
My concern is regarding the "Legend of Zelda: Ocarina of Time" and I'm trying to get it working with the Project64 emulator. After searching for a considerable amount of time on the internet, I realize that the "unhandled opcode" error has occurred more often than not, in the past.

I'll shortlist the details of my ROM, emulator version, along with whatever I have done so far, below:

Emulator: Project64, v1.6
ROM: Legend of Zelda, The - Ocarina of Time (E) (V1.0) [!].n64
CPU: Intel Core i5-2500K Processor - 3.3 GHz
RAM: Corsair 4GB
GPU: AMD Radeon HD 5750
OS : Windows 7

As you can see, there is no problem with the rom as it is a "[!]". I have already checked and verified the ROM using GoodN64:

You have 2 of 2477 known Nintendo 64 (0.999.9a BETA) ROMS
Legend of Zelda, The - Ocarina of Time (E) (V1.0) [!]
Legend of Zelda, The - Ocarina of Time (U) (V1.2) [!]

- Also, I have updated the "Project64.rdb" file within the installation directory.
- Furthermore, I have also tried using a different plugin with Project64, i.e. "Direct64 v0.5.03.20", but that didn't help either.
- I must also clarify that I was using the native save game option and not a "save state" created by Project64.
- I have also tried completely uninstalling Project64, removing all temp. files and obsolete registry entries, restarting the computer, then re-installing Project64 and the error still prevailed. Then, I also tried again copying over the updated "Project64.rdb" to the installation directory and I was getting the same error.
- I wasn't using any cheats, whatsoever.

How to reproduce the error ?

- Use "Legend of Zelda, The - Ocarina of Time (E) (V1.0) [!].n64" on "Project64, v1.6".
- Start the game and move link to the lost woods.
- Take a left, visit the skull kid, stand on the platform next to him.
- From the skull kid room, move left again to the next area.
- Make your way back and try to exit Lost Woods.
- You will get the error I'm talking about each and every time.

Another way to reproduce the error:

- Use "Legend of Zelda, The - Ocarina of Time (E) (V1.0) [!].n64" on "Project64, v1.6".
- Proceed through the game normally, avoid the lost woods.
- Defeat "The Deku Tree" dungeon.
- Visit Hyrule Castle
- Visit Kakariko Village
- Exit Kakariko Village
- You will get the error I'm talking about each and every time from this point onward.

Here is a screenshot of the error which comes up:

Unhandled R4300i OpCode at: 801E7400
Unknown 73 73 00 00
stoping emulation !

As it might be apparent, I've tried so many options and combinations of those options that I've hard-burned the starting portion of the game in my brain. Any help in this regard will be exceptionally helpful.

 

[Fanatic 64]

Change the Self-modifying Code Method to "Protect Memory". Then switch it back to "Check Memory Advance" because Protect Memory causes other issues.
Or purchase Project64 2.0.
The issue is well-known. No need to describe it on detail.

P.S. Your GoodN64 is horridly outdated. Also, where did you got the RDB from?

 

[dx01110]

Change the Self-modifying Code Method to "Protect Memory". Then switch it back to "Check Memory Advance" because Protect Memory causes other issues.

I remember trying "Check Memory Advance" and it not making any difference. But I'll give both of those options a shot. Will report back.

P.S. Your GoodN64 is horridly outdated. Also, where did you got the RDB from?

Okay, could you please link me to an updated source for GoodN64? Thanks.
RDB was obtained from the "pj64-emu" website, downloads/updates section. (Couldn't post the link)

EDIT: Tried what you suggested above.

- Started the ROM.
- Options -> Settings -> ROM Settings -> Self-modifying code method = "Protect Memory".
- Loaded the native saved game.
- Went to the Lost Woods, skull kid.
- Tried exiting.
- Still the same error.

 

[Agozer]

Use the 1.0 US NTSC version, and see if that changes things. Don't play PAL games unless you must have multiple languages in your game.

 

[Toasty]

P.S. Your GoodN64 is horridly outdated.

Perhaps so, but the version he used was obviously sufficient to establish the integrity of these particular ROMs. I don't think that the checksums for the original N64 OoT ROMs have changed recently, have they?

@dx01110:
My complements and thanks for both doing your own research beforehand, and providing a very comprehensive explanation of your problem, specs and troubleshooting steps you've already taken. It's a welcome contrast to most newcomers who don't bother to search for answers first and then proceed to ask questions without giving nearly enough information in their first posts.

Do the problem areas present when you use the NTSC (U) version of the game? I recall that PAL (E) versions of the game tended to have more issues (in addition to a somewhat slower framerate).

EDIT: Aw, Agozer beat me to the punch.

 

[squall_leonhart]

RDB was obtained from the "pj64-emu" website, downloads/updates section. (Couldn't post the link)

EDIT: Tried what you suggested above.

use the rdb from http://www.emutalk.net/threads/49385-PJ64-Unofficial-RDB-v4-23-by-Nekokabu-amp-MASA

 

[Fanatic 64]

Perhaps so, but the version he used was obviously sufficient to establish the integrity of these particular ROMs. I don't think that the checksums for the original N64 OoT ROMs have changed recently, have they?

I remember about a Ocarina of Time (E) ROM that was deemed good at first but then discovered to be a bad dump.

Latest GoodN64: https://dl.dropbox.com/u/98424635/GoodN64_V321.zip
I imagine you downloaded the RDB from here: http://www.pj64-emu.com/downloads/project64/updates/

EDIT: Nevermind, it was Ocarina of Time (U) (V1.1) which was a bad dump.
Also, the GameFAQ advices seting Self-modifying Code Method to "Change Memory" for thay specific part (I said "Protect Memory" because I trough it was the most likely workaround).

 

[dx01110]

#Fanatic 64: Thanks for the link. I've used that latest version (v3.21) of GoodN64. Here are the results:

You have 2 of 3389 known Nintendo 64 ROMS (V3.21)
Legend of Zelda, The - Ocarina of Time (E) (M3) (V1.0) [!]
Legend of Zelda, The - Ocarina of Time (U) (V1.2) [!]

#squall_leonhart: Thanks, I'll use that updated RDB.
#Toasty: Thanks for the appreciation. I can understand how useless it could be to just complain about things "not working", while providing no information that would help someone helping you. Another thing that's awesome are pleasant and welcoming members. Thanks.
#Toasty & Agozer: Before I read your post regarding trying out an NTSC version, I did the following:

- Start Project64 afresh.
- Either in the game browser, or after manually loading a ROM, change Options -> Settings -> ROM Settings -> "Self-modifying code method" to "Protect Memory".
- Don't use the native saved game(s) (if any)
- Instead, start a new game.
- After gaining control of Link, head on to Lost Woods -> (left) Skull Kid -> stand on the platform next to the Skull Kid -> (go left again) -> Exit Lost Woods.
- This will confirm that you don't get the error again, rather than playing quite a lot and then running into this error.

Sorry to be detailed/descriptive in the above instructions. I confirm this as a sure-fire working solution to the Lost Woods crash, so I just wanted anyone running into the same problem to be able to sort it out quicker than I did.

However, I still have some questions left:
- Does using "Protect Memory" all the time while playing the game trigger any known bugs/stability issues? As far as I've heard, the only repercussion by using "Protect Memory" is that the game will perform slower than usual and that this option is generally the most stable option that could be selected.

I'm asking this because I don't notice any performance degradation after using this option so I might be interested in keeping it that way, if its not a problem. All the other options I've tried cause a lot more bugs and issues (comparatively) , as per my experience.

As far as the NTSC version is concerned, I'll be following your advice(s) and using the NTSC version instead. Thanks again, for the speedy responses.

 

[squall_leonhart]

Check Memory is what gets past this issue, not Protect Memory.

Zelda64 needs to be able to modify code to emulate correctly.

 

[dx01110]

Check Memory is what gets past this issue, not Protect Memory.
Zelda64 needs to be able to modify code to emulate correctly.

Okay, so as I asked in the previous post, can someone answer this:

- Does using "Protect Memory" all the time while playing the game trigger any known bugs/stability issues? As far as I've heard, the only repercussion by using "Protect Memory" is that the game will perform slower than usual and that this option is generally the most stable option that could be selected.

I'm asking this because I don't notice any performance degradation after using this option so I might be interested in keeping it that way, if its not a problem. All the other options I've tried cause a lot more bugs and issues (comparatively) , as per my experience.

 

[dx01110]

I just confirmed this:

Using "Check Memory Advance" or "Change Memory & Cache" will NOT solve the issue. You will still get the error if you select one of those.
Then after trying those two options, I again re-opened Project64, again, changed it back to "Protect Memory", deleted all old games, started a new game. I can now again exit as many times I want without being pestered with error codes or bugs. Protect Memory is the only option which appears to resolve the error.

Ideas ?

 

[Fanatic 64]

Did you also try "Change Memory"?

That's a rather interesting workaround trough. I'll try it and see if it also works for me.

95% or so of the time "Protect Memory" doesn't cause any additional problems, trough Ocarina of Time has different problems with all Self-modifying Code Methods.

 

[dx01110]

Did you also try "Change Memory"?

Well, for me, the only option relevant within the drop-down menu with what you are suggesting is "Change Memory & Cache". I have tried that with the "clean" procedure that I described, i.e. starting a new game, re-opening everything etc. I still kept getting the same error as described in the initial post.

Thanks to the "Protect Memory" option, I've already played till my first trip to hyrule castle, no problems so far. I can go anywhere (skull kid, lost woods) and exit from anywhere as much as I want. I Will report back if I catch a problem with the "Protect Memory" option. It appears to be pretty flawless, though. Also, I'm now using the NTSC version as suggested, and its much more better and faster as compared to the European/PAL version.

 

[Fanatic 64]

For me, using "Protect Memory" with a 100% complete save, and standing on the platform and exiting, does NOT cause a crash. With "Check Memory Advance", the emulation dies with "Unhandled R4300i OpCode at: 801E8C80 Unknown 73 73 00 00".

Have you tried a "dirty" save with the (U) ROM and "Protect Memory"?

 

[dx01110]

Have you tried a "dirty" save with the (U) ROM and "Protect Memory"?

No, ill try this later. But I can confirm that a "dirty" save with the (E)/PAL version of the ROM will still crash the game even if using "Protect Memory".

For me, using "Protect Memory" with a 100% complete save, and standing on the platform and exiting, does NOT cause a crash.

Yes, Protect Memory is the only thing that resolves the issue. You could also try going into the next area (left again from the skull kid area), after standing on the platform and then leaving Lost Woods to be extra-sure.

 

[dx01110]

Completed the game without any crashes / bugs / problems, whatsoever. Select the "Protect Memory" option and keep it that way for the rest of the game. There are no repercussions of using it.