It is currently Tue Jul 16, 2019 5:59 pm

All times are UTC - 7 hours



Forum rules


1. NO BLATANT PIRACY. This includes reproducing homebrew less than 10 years old, with the exception of free software.
2. No advertising your reproductions, with the exception of free software.
3. Be nice. See RFC 1855 if you aren't sure what this means.



Post new topic Reply to topic  [ 7 posts ] 
Author Message
PostPosted: Thu Feb 28, 2019 2:36 pm 
Offline

Joined: Thu Feb 28, 2019 2:27 pm
Posts: 7
I am new to making games but I love the SNES and it has certainly opened the door wide open as to new games I will get to play. I am currently working on making Zelda Parallel Worlds. I have a donor and have loaded the game onto a 27c160 EPROM. I have wired it into the cart number 2 because the first one didnt work (come to find out i was drinking when i made it and wired pins 17-32 backwards which is now corrected). Both games do the same thing. They boot the first message saying the maker of the game and then the song starts to play but nothing shows on the screen. I am am trying to finish this soon to give to my cousin as a gift for his baby shower. Anyone have any thoughts on this? I found another thread that had the same issue and it was a bad solder point which I will be checking. But in the other thread he was using 2 27c801 chips which fits very differently into the game. Which maybe is the way i should be doing it. Any help would be great. So far i have made Dark Law and Chaos seed


Top
 Profile  
 
PostPosted: Fri Mar 01, 2019 10:06 am 
Offline

Joined: Thu Feb 28, 2019 2:27 pm
Posts: 7
Update: I have cleaned the pins of the cart and looked over the soldering. everything seems to be in order. after cleaning the pins i feel like the games starts a little more promptly as far as showing the Hacks creator name. But then still goes to a black screen and plays the song. I know that the tri-force should be flying in but it never happens. I let the song play for a bit to see if anything changed but it jsut plays no problem and never moves on. I also have tried pressing buttons on the snes controller to check if I can get anything to happen in the background but there is no response just that song taunting me of an awesome game that i want to play but currently cannot. I'm starting to wonder if I should change my reproduction method and switch over to 2 27c801 chips as I have read that others have made it this way.


Top
 Profile  
 
PostPosted: Fri Mar 01, 2019 7:37 pm 
Offline
User avatar

Joined: Sun Sep 19, 2004 9:28 pm
Posts: 4152
Location: A world gone mad
Possibilities here are endless. I'll start with some basics, in no particular order. I will bold/underline my questions; please answer those

1. I don't know what Zelda Parallel Worlds is, but I suspect it's a romhack. Confirmed -- https://www.romhacking.net/hacks/197/

Do you have any confirmation that this romhack actually works on a real SNES with proper boards (i.e. not SD2SNES or other flash carts)? You keep referencing these nebulous "threads" where people "found problems with solder points" but you aren't giving any actual links to said threads.

Most romhacks are tested on emulators only; not a lot of romhackers have flash carts or wired EPROM boards so they often can't test on hardware. I'm not saying this is the case here, but it is a normal practise. (I was part of the core romhacking community from its inception until, oh I don't know, 2010?)

Looking at the romhacking.net comment history for this romhack, it looks like the hack goes back to *at least* 2009. Which brings into question: if there are multiple releases of this romhack, which one are you using? And is that same version that said "people in threads" were using?

The situation becomes even more complicated if the romhack actually expanded/grew the ROM (ex. up from 8mbit to 16mbit). More on that in a sec.

2. What exact PCB model are you using? Knowing exact PCB version is important, not just a vague claim of "donor board"; it's very possible the board you're using is not of the correct type, e.g. addressing lines from the mask ROM don't go where they should for this game. But that's just one of many possible problems.

3. What speed EPROMs are you using? You want 120ns EPROMs to ensure full compatibility; it's not worth explaining why (has to do with the SNES's fastrom and slowrom modes)

4. The size of the romhack matters. Is it 8mbit or 16mbit? Here's why I ask:

2C7801 EPROMs are 8mbit (1MByte). If the game is 8mbit, then only one of these chips is needed. If it's 16mbit then 2 will be needed, alongside a 74HCT139 multiplexer/decoder, then get to wire all that up.

27C160 EPROMs are 16mbit (2MByte), which means for an 8mbit game you'd need to (IIRC) double the ROM. For 16mbit, it should work fine.

Both types require custom wiring on a donor cartridge, because SNES/SFC mask ROMs aren't pinout-compatible with said EPROMs.

5. Are you sure your EPROMs are good? There's been a huge trend of people selling supposedly "new" EPROMs that are actually used and bad/flaky, on places like eBay and elsewhere. There's no way for you to know they're flaky/bad or used without testing them.

6. Does the ROM you're using actually load/work on emulators? If so, which emulators (and versions) did you use?

7. Not a question, but: please provide good high-res photos of the board (front and back) you're working on, as well a clean write-up of your wiring modifications. This can help answer some of the questions I've asked, as well as potential explanations for what's wrong. Photos are super helpful here. Take a look at some of the other threads in this sub-board and you'll understand why. We do have lots of quality hardware-savvy people here.


Top
 Profile  
 
PostPosted: Sat Mar 02, 2019 10:59 pm 
Offline

Joined: Thu Feb 28, 2019 2:27 pm
Posts: 7
So I have made 2 games you can tell which is which because I changed colors on the wire I used.
Image
Image
Image
Image
Image
Image

I am using the Zelda 3 parellel worlds V1.3.
Image
Image

Im wiring it using this diagram
Image

I am using a USA copy of Super Baseball Simulator 1000 as the donor the specs are as follows:
Bank: Lowrom
Sram: 64
Chips: Normal + Battery
Size: 4
Video: NTSC
Region: USA
Speed: Slowrom
The boars has a number on the side I don't know if this is helpful but its SHVC-1A3b-13

I used a:
M27c160
100F1
88802
01141
chip made in Singapore

Pin 42 on my chip has been tied to the A20 pin on the board which i found to be pin 2 on the SN74S139AN chip

The patched game does load on the computer. I am using the Zsnesw emulator

I assume the eproms are good. I always nuke them with an eraser first just to make sure but I have made other games with the same batch of chips and they have worked fine. However if they are bad I wouldn't know how to tell other than getting errors when I try to program them.

Zelda starts as a 1MB game and then after I apply the patch it goes up to 1.5MB. I then used Lunar Expander to bring it up to 2MB

Link to the mentioned thread I found about someone having similar issues:
https://forums.nesdev.com/viewtopic.php?t=8177
On page 3 of the thread someone mention my exact same issue of the game starting and getting the Euclid Presents message and then the song plays but you get just a black screen.


Top
 Profile  
 
PostPosted: Sun Mar 03, 2019 5:02 am 
Offline
User avatar

Joined: Sun Sep 19, 2004 9:28 pm
Posts: 4152
Location: A world gone mad
Thanks for the photos. Someone else (i.e. not me) will need to review them to see if there's anything obvious wiring-wise that looks odd or wonky.

I also won't be able to tell you if that wiring diagram is correct or not; someone more familiar with hardware could.

The thread you linked me is just filled with people not really providing "linear, easy-to-follow" details -- the people trying to do the repros there spew verbal diarrhoea with little details, due to not being technical This is incredibly common with reproduction-related threads/things, sadly. Not your fault of course, but threads like that are usually impossible to glean useful information from.

My below words are going to jump around a bit, and for that I apologise, all of this is intertwined. Apologies for it not being clear (esp. right after judging other people in threads).

I think the complication here lies in regards to the ROM expansion that's going on, but I don't know for sure. I'd have to actually sit down with a debugger and see what this romhack is doing, bank and code-wise. What I do know for certain: the original Zelda 3 is is 8mbit (1MByte) mode 20 slowrom, and the romhackers of this particular game expanded it to 12mbit (1.5MByte) mode 20 slowrom. What's confusing about this is: there is no real 12mbit "model" or "method" on any of the SNES production PCBs. I'll get back to this in a moment when talking about PCBs. They really should have extended it to 16mbit and then all of this would've just worked.

The best you can do is go with 16mbit (2MByte) and make sure your addressing lines are wired a specific way to deal with the 4mbit (512KB) difference by mirroring those contents to specific banks (I think through A20 on the SNES), *or*, do some very bizarre hackery with the ROM itself -- which I believe is what Lunar Expander might be trying to do I should add I quite literally have never understood how that tool/program can work, given that addresses are hard-coded into the game at assemble-time of where things should be, and if they're not, things break -- often weirdly, sometimes in the exact fashion you describe. Other times you might just get nothing (i.e. a crash).

Another option might just be to copy the upper/last 512KB and append that to the file itself (thus the last, and second-to-last, 512KByte regions would be the same) and hope for the best. Maybe that's what Lunar Expander does in this case, I don't know.

That thread you link, though, in this post mentions something called "swap bin", which I believe is referring to some feature of this tool but I have no idea what it's doing. It also mentions addressing line A19 on the 27C160, which pertains to exactly what I just described above, re: "mirroring".

...oh, wait a minute, the person in that thread who said that was talking about the previous fellows' 27C801. Oh look, in a completely different thread here someone describes something similar.

While looking for a 27C160 pinout, I found this useful piece of information that says that the 27C160 won't work at all, with some forum reference? I didn't care to look into it.

Okay, here are the respective pinouts for the 27C160 vs. 27C801:

* 27C160 = https://www.dataman.com/media/MROM27C160.png
* 27C801 = http://www.jaskagaming.com/wp-content/u ... rison1.png (also has SNES mask ROM pinout)

Yeah, these two are completely different. The 27C801 looks a lot easier to deal with, IMO. Although it's a 8mbit (1MByte) chip, so it wouldn't fit a 12mbit ROM. I guess that's why people are trying to use the 27C160. :-)

ALSO in that thread, flagoss mentioned that there seemed to be a bug/problem with the romhack and he had to patch it. Later on, blurayno mentions some OTHER kind of patch, but because he provides no context I don't know if he's talking about the German spin-off or what. Like I said about this stuff: nobody ever communicates coherently so it's impossible to know what the heck is going on 6 years later.

***ALSO*** in that thread, later on, there's some other patch mentioned, blah blah blah.

Supposedly the process that worked is here but again, subsequent posts after that claim to have problems (though they claim it was due to a through-hole wiring problem/mistake and had to use a different donor PCB as a result -- sounds like they tore/damaged the through-hole wiring when desoldering/removing the existing mask ROM, which is quite common). But the users don't specify what they had done up to that point WRT the ROM, etc... Starting to see why I asked for details of what exact version of the romhack you're using, etc.? It all matters. For all we know right now your wiring could be fine and this is some quirk/bug in the actual romhack itself, depending on what "version" or "patch" you're using. There are so many variables here that it's ridiculous. I see from your screenshot that the filename ends in v1-3 but I dunno what that means exactly.

About PCBs: yes, SHVC-1A3B-13 is helpful. That's a production PCB (meaning it uses mask ROMs, as you already know) works with mode 20, is wired to support up to 16mbit ROMs, and has 64KB SRAM that's battery-backed. It should be OK to use (the SHVC-1A3B-12 should work too, or ). The source of this information I'm using is here; if you look through the PCB list you'll see there's quite a lot of variance due to what models/PCBs were available at Nintendo at the time of release in a particular country or time. That board you have from Super Baseball Simulator 1.000 should work perfectly though.

Wouldn't it just be easier to buy a repro board, specifically this mrTentacle board that supports 27C322 and *also* 27C160 (read the description), to make all of this easier? They look affordable, including the additional chips/parts needed which he also sells as a parts kit.


Top
 Profile  
 
PostPosted: Sun Mar 03, 2019 9:20 am 
Offline

Joined: Thu Feb 28, 2019 2:27 pm
Posts: 7
I can confirm that at least using 2 27c160 chips in parallel works as shown below:
Image
Image
I have played and confirmed the function of this game however it is running in a 36 pin board not a 32. however the difference in the wiring is 1 pin which is pin 42. thus on the 32 pin board of my Zelda cart i had to find an alternate place to tie into A20 which I did. I do suspect that the version of the game I am using might have issues but I wouldn't be able to identify this. I will try downloading an alternate version and see what happens when i place it in the board. Thanks for your help and information so far.

As for why dont I use the boards mrtentacle has. I do have some adapter boards from him for the purpose of using 27c322 chips. I just like to take things apart and in this case rework them into something new. Im sure his boards are amazing just not my proffered method

Also my understanding of the programs is this:
Ucon64 - checks the rom and sees if its whatit designates as a SNES game with all the right values
Lunar Expander - fills the end of the game with blank data for the purpose of having a full chip thus if a game ends at 1.5MB the last 512kb will be filled with 0000 for the purpose of taking the space
IPSandSUM - verifies that the checksum values are correct and if they are not re-writes them or changes them however it does that that they match what a SNES cart would be.

I ran all of these programs after I expanded the game and changes were made by these so that when I checked the game using Ucon64 according to it I had the green light. Now I know very little about what they are actually doing or if Ucon64 is always right which in this case I think we can say its not unless I have a bugged version. But in the past this has worked for me. However in the past i have dealt with games that are an even value in size and there was no need to use Lunar Expander so maybe this is my issue. I did find the supposed hard version of Parallel Worlds and it was 2MB in size. But I went for the Remodel which is brought back down to easier playing and it was smaller.


Top
 Profile  
 
PostPosted: Sun Mar 03, 2019 4:13 pm 
Offline

Joined: Thu Feb 28, 2019 2:27 pm
Posts: 7
So. After looking into other forums I am convinced that the version of the game I am trying to use is not made to run on the actual SNES. I am basing this off of information i got from this thread.

https://www.romhacking.net/forum/index. ... ic=17732.0

So. in this they talk about changing lines in the code and what not but I have no experience with that kind of thing and don't trust myself. Maybe i'll try it in the future. For now I am going to continue doing research and see if I can find the version that does work.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 7 posts ] 

All times are UTC - 7 hours


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group