The BAD ROM PAR workaround/Hex-edit thread.

[Redifer]

I figured we should have all this in a thread. Chilly Willy has already posted information for getting two ROMs that don't normally load on the Mega ED to load by using Pro Action Replay codes or using a Hex editor to change certain values so that the ROM loads every time.

Dragon's Revenge
Use PAR
00036C:4E71
or Hex edit the byte at offset $36D from $70 to $71

Harry Potter
Use PAR
186B52:5345
186B66:5345
or Hex edit the the words at $186B52 and $186B66 to $5345.

Since Chilly Willy is bad-ass, he has suggested that if you have a ROM that won't load on the Mega ED to let him know as he can usually figure out a way for it to work. But please, make sure you've tried loading other versions of the same ROM as well as you may simply just have a bad ROM.

[Redifer]

OK Chilly Willy, how about Thunder Blade on the SMS?I can't seem to get it to work on the Mega ED.

Nevermind, I had the wrong mapper selected.

[cleeg]

I read on another thread that EA games can be made to work using codes and such.  Can the Strike Series be worked around in this fashion?  My ROMS are all ported direct from actual carts using a Retrode USB device, and should I assume, be "good" ROMs.

Thanks.

[Chilly Willy]

Which games exactly? I seem to remember something about the Strike games over at Sega-16, but from my searches over there the other day, it looks like all the GameGenie threads were lost in the great hacking incident the year before.

[cleeg]

Sorry if this is already widely known, but I found a way to use the ingame menu with some of the problematic EA games that boot to a black screen when ingame menu is enabled.

I found that for some games when a proper game genie master code is entered, the game will work with ingame menu enabled. 

Here's a couple I tested that work:

The Haunting: RH2B-86T2
Might and Magic: R18A-06WJ



« Last Edit: December 29, 2012, 11:35:57 am by b0tulinium »

This was to what I was referring in my last post.

[Chilly Willy]

Well, again we'd need to know which game... for example, if you meant Desert Strike, the master code (from here) is RH9T-860E. You could try it to see if that works.

[JimmyMz]

Chilly Willy,
What about Balloon Boy (Everdrive MD) are you able to play that game successfully (it boots up fine, but displays a message)? Do you even have an Everdrive MD? Common sense tells me you wouldn't buy both the Mega Everdrive and the Everdrive MD, but I could be wrong. Regardlessly, do you know a way to correct it, even if it's on the Everdrive MD, so the game doesn't display the "this is an illegal cartridge" message?

[Chilly Willy]

I sold my EDMD to someone at Sega-16 who couldn't make overseas purchases and got myself a MegaED. And yes, I get the same message from Balloon Boy. I'll check it out and see if I can make a hack for it.

[Drakon]

Hold on....why not get krikzz to fix this with his awesome OS updates?

[JimmyMz]

I sold my EDMD to someone at Sega-16 who couldn't make overseas purchases and got myself a MegaED. And yes, I get the same message from Balloon Boy. I'll check it out and see if I can make a hack for it.

Thank you for checking, and giving it a shot.

[dvd2vcd]

why not hex edit the roms and post them

[JimmyMz]

why not hex edit the roms and post them

This isn't really a great idea, it's a slippery slope, and for obvious reasons...but who knows, maybe krikzz doesn't mind his website becoming a ROM distribution website.

[dvd2vcd]

why not hex edit the roms and post them

This isn't really a great idea, it's a slippery slope, and for obvious reasons...but who knows, maybe krikzz doesn't mind his website becoming a ROM distribution website.

actually thinking about it he probably wont like that idea

[Chilly Willy]

It's better to just post patches. The roms can be gotten in plenty of places.

I looked at Balloon Boy... it's actually a two-in-one cart called Funny World & Balloon Boy. Balloon Boy is the first game in the rom, while the other half of the rom is Funny World. Hardware in the cart switches between the two halves, and without that extra hardware, both games fail with the same message.

The first step is to split the rom into two roms of 256KB each, then they need patches to pass without the hardware... I'm still working on that step.

EDIT: After finding one place to fix, it turns out I didn't need to go through all that work. Found this with a little googling...

Oh well. Anywho, the fix is to nop out three calls, one at $504, one at $656, and one at $3D84. The PAR codes would be

000504:4E71
000506:4E71
000508:4E71
000656:4E71
000658:4E71
00065A:4E71
003D84:4E71
003D86:4E71
003D88:4E71

You don't need to split the roms, but you do need to use the Balloon Boy version of the rom, not the menu version. The menu version still have the exception table at the start for starting the menu to select which game to run. It won't run Balloon Boy since it lacks the Balloon Boy exception table.

[JimmyMz]

The fix is to nop out three calls, one at $504, one at $656, and one at $3D84.

Nicely done Chilly, +1 to you. It works great! I appreciate the time you put into this...Thank You Sir.

For those who don't understand:
In a Hex Editor, go to search. Enter the six digit number, that is located before each colon, in each of the three sets of numbers below, and select okay. The Hex editor will bring you to that address location in the ROM...now simply enter the 4 digits after the colon at the ROM address location that the Hex Editor just directed you to. Do this same procedure three times (one for each set of numbers listed below), at the end of the three entries, save the ROM file, and go boot it up!

000504:4E71
000656:4E71
003D84:4E71