Ms Pac freeplay w/ attract mode?

Okay, BC is apparently not what I'm looking for. Started over again and got it to = 00 and it's still failing the checksum.

EDIT: That's with -all- the values from the breakpoint the same on both the normal and hacked 6E.
 
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This is what I'm seeing in the debugger. Any tips would be great? Am I at the wrong break point or what? I'm breaking at the point where the checksum is disabled. Changing that "20 15" into "00 00" removes the check so I figured that's where I should be breaking, right?
 

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Okay, got it. Works now!

I'm just having a new issue with the "FREE PLAY" text on the bottom of the screen... it just says " REE PLAY" now, but everything else seems to be working.

I hate to keep asking, but I know nothing about assembly. Any idea how the "F" is coming up missing now? Could that just be a MAME issue? The "F" appears for a split second, then vanishes.

EDIT: The problem was I wasn't cycle'ng through all the times it checked the checksum... lol, I was just breaking at the first one. ... I'm dumb. But I un-dumbed myself and saw where it was failing.


EDIT2: Ugggg... nevermind... checksum balances... but now inputs don't work in freeplay mode... won't see coins or starts...
 
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Okay okay... uggg... FINALLY think I'm 100% done... ...

I hope. Plays perfect in MAME, attract mode doesn't screw up... the F is back... maze is the right color... ... I'm going to burn the thing and put it in my machine and play it for a while.

Wish me luck.

If everything works out, I guess I'll either be giving some ROMs files away or selling some chips if anyone is interested?... either or... wish me luck!
 
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Scucci said:
Okay okay... uggg... FINALLY think I'm 100% done... ...

I hope. Plays perfect in MAME, attract mode doesn't screw up... the F is back... maze is the right color... ... I'm going to burn the thing and put it in my machine and play it for a while.

Wish me luck.

If everything works out, I guess I'll either be giving some ROMs files away or selling some chips if anyone is interested?... either or... wish me luck!
Click to expand...

Good luck!
 
Scucci said:
I'm using the built in checksum tool in Hex WorkShop. I've never had any problems with it before. I have it set at 16-bit.

I have a breakpoint set in MAME at 301A jr nz,$3031. I'm seeing two different values, in the MAME debugger, between my hacked 6E and the original 6E. I have no idea what these values mean... I'll start reading up on the debugger and see if I can figure something out. In the mean time, please feel free to keep helping. lol
Click to expand...

#1 it uses an 8 bit checksum, not 16...
#2 it may only checksum the even bytes for some unknown reason...
 
Scucci said:
I'm assuming (since I don't actually know assembly) that BC is what I need to be 00?
I was originally at 94, after plugging in FF in all of the spare noops at the end of the ROM I've managed to get it down to 39... there has to be a better way to get that down besides plugging in FF, right?
Click to expand...

Just change a single byte at the end of the file to whatever it needs to be to make the checksum match.
 
HudsonArcade said:
Just change a single byte at the end of the file to whatever it needs to be to make the checksum match.
Click to expand...

I did, some of the NOOPs there are a little weird... depending on where the checksum fix was it would either make the F vanish, make the game not take inputs, or it would just make the game reset as soon as it either went into attract mode (marquee) or tried to show a maze (attract mode or game play).

I finally have it where it works in MAME 100%, but I can't trust my Willem programmer... I've tried it 3 times and each time it causes a ROM 0 error (exact same code that's working in MAME). Does anyone have a programmer and a Ms PacMan machine (and a spare chip) want to give it a shot?

EDIT: And to make the checksum work I had to edit 1 byte total, but it was a few spaces apart (not sure of the right word)... It seems to check run the checksum routine several times and a change in 6E would make the checksum check find different values each time. I had to fix it for one check, then another, then another, then another... and after all was said in done, I ended up with just 2 bytes being different than the original NOOPs.
 
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I've got a Ms Pac and a burner. PM me and I will reply with my email address, so you can send the binary. I'll burn it and test it tonight when I get home.

ken
 
Whoops... Are you doing this on an *original* mspac w/ aux board?

That's a little sketchier, since it does do multiple checks due to all the address remapping, etc.
 
Okay, I'm pretty sure it's an EPROM issue now.

I took my original 6E off the board, and copied it to another 2532 I had laying around. I put that new chip in and even with the original code, it's still giving a ROM 0 error. So... that's weird.

I've taken the new code, put that on a chip... then read it off that chip and plugged the copied code, that I just read off the new chip, into MAME and it works fine. So... something on my board does NOT like the 2532's I'm using...

I sent the BIN you YellowDog and hopefully he'll have better luck with his chips? I guess we'll find out in a little bit.

Does anyone know why the PCB wouldn't like a new 2532 going into a socket that a 2532 just came out of? I've tried 3 different new 2532s and it won't recognize any of them properly.

EDIT: For the record, the original chip is a Motorala, the new chip is Hitachi... both 2532s though... is there some difference I don't know about?
 
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Bad luck. I just finished swapping it in and got gibberish all over the screen. No love.

I am going to swap it back now and make sure Ms P comes back up.

Back in a few.

ken
 
YellowDog said:
Bad luck. I just finished swapping it in and got gibberish all over the screen. No love.

I am going to swap it back now and make sure Ms P comes back up.

Back in a few.

ken
Click to expand...

Frick... the thing works perfectly in MAME... there must be something going on on the boards that isn't happening in MAME.

I guess I might have to just make it a 2 chip solution... I hate doing it that way, but damn son.

Thanks anyways, YellowDog.
 
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Ms Pac freeplay w/ attract mode. Please help check the code.

Well... here it is for anyone that wants to check it out and see where I'm screwing up.

PLEASE have a look at it... I really want to call this done already.

EDIT: That's just the 6E rom, it'll run in MAME without the patch 6J (checksum disable hack)

EDIT: attachment removed, bad code.
 
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Just make sure, I burned an image of the original 6E ROM as well and it works perfectly. So it is not the ROM types.

It's going to be a while before I can test again. I thought I fried my Ms P board on the last test. I blew 3 of the 4 low power fuses because I didn't get the edge connector on just right. I replaced the fuses and reseated the board and everything is fine. But I scared the crap out of myself for a minute. When I inspected the board I did find the 2200 mF cap up by the edge connector was cracked, so I am goging to replace that before I put Ms P back together again. I don't know if it was that way before or it is new. It probably was that way, but I'll fix it anyway.

Bummer. I was hoping to get rid of the static free play page. Oh well, thanks for trying. Maybe we can get it fixed if everybody looks at it collectively.

As a start, here is the original 6E ROM image from my Ms P.


ken
 

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mattosborn said:
No, it's not necessary... but if you're planning on making any significant changes then it will certainly make your life easier to do so.
Click to expand...

You missed my point- nevermind.

And guess what, per the last post- the code is hanging at *self test*

Splitting hairs........
 
Yeah, that's what I'm aiming for... I put all of my machines at home on freeplay... and the MS Pac FP screen bugs the hell out of me!

It's just really weird how it works in MAME, but not on the actual boards... I thought they strived for exact emulation on MAME?... I'd hate to think they cut corners somewhere.

Just to be sure I'm working with a good Romset, I'll probably copy all of my original chips and double check to make sure everything is adding up correctly compared to the MAME romset that's been floating around forever.

I'm sorry you almost peed yourself with your machine... I hope everything turns out alright.
 
Just so we can all compare, here are the part numbers on the ROM labels that are still on my ROMS:

6J = 0073-M932D-27X0 PAC-MAN (c) Midway 1981
6H = MS-C (c) Midway 1981
6F = 0073-M932B-27X0 PAC-MAN (c) Midway 1981
6E = MS-A (c) Midway 1981
5F = 0595-00803-0500-5F MS PAC-MAN (c) Midway 1981
5E = MS 5E (c) Midway 1981 (handwritten)
U5 = MS-U5 (c) Midway 1981
U6 = 0595-00803-0200 U6 MS PAC-MAN(c) Midway 1981
U7 = 0595-00803-0300 U7 MS PAC-MAN(c) Midway 1981

Looking at it, mine is a Pac-Man board part number A082-91375-B000.

ken
 
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