Missile Command ROM 035822-03e Whats the Diff?

JoeB1355

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I'm trying to figure out what the difference is in the ROM version

Its appears to only be an upgrade to just this 1 chip

I dumped it and compared it to a 02 version here are the diff's

bash-3.2$ od -t x1 035822.02 >02
bash-3.2$ od -t x1 035822.03e >03e
bash-3.2$ diff 02 03e
4,9c4,9
< 0000060 b9 da 01 65 d3 99 da 01 85 d3 d8 a9 ff 85 d4 60
< 0000100 a5 f4 29 70 c9 70 f0 39 4a 4a 4a a8 a9 00 85 8d
< 0000120 a6 b9 bd d8 01 85 98 bd da 01 85 99 f8 a5 98 38
< 0000140 f9 82 60 85 98 a5 99 f9 83 60 85 99 30 02 e6 8d
< 0000160 10 eb d8 a5 8d 38 f5 c3 18 75 c0 95 c0 a5 8d 95
< 0000200 c3 60 00 01 20 01 40 01 50 01 80 01 00 02 80 00
---
> 0000060 b9 da 01 65 d3 99 da 01 85 d3 a9 ff 85 d4 d8 60
> 0000100 a5 f4 29 70 4a 4a 4a 4a a8 b9 7b 60 85 99 f0 ef
> 0000120 a6 b9 bd d8 01 4a 4a 4a 4a 85 98 bd da 01 0a 0a
> 0000140 0a 0a 05 98 f8 38 f5 c3 38 e5 99 90 d1 f6 c0 48
> 0000160 b5 c3 18 65 99 95 c3 68 4c 68 60 10 12 14 15 18
> 0000200 20 08 00 01 20 01 40 01 50 01 80 01 00 02 80 00
11c11
< 0000240 10 12 14 d0 e0 c0 08 a0 60 40 20 10 0a 06 04 02
---
> 0000240 11 13 16 d0 e0 c0 08 a0 60 40 20 10 0a 06 04 02
44,49c44,49
< 0001260 fd fc fb a9 00 85 9a a2 13 bd 6e 01 f0 14 85 9c
< 0001300 bd 39 01 85 9b bd c2 01 85 b5 20 71 5e a9 00 9d
< 0001320 6e 01 ca 10 e4 a9 fc 85 ec a2 13 ad 0a 40 29 07
< 0001340 09 03 9d c2 01 85 9a ad 0a 40 9d 39 01 85 9b ad
< 0001360 0a 40 c9 d0 b0 05 c9 38 b0 03 38 b0 f2 9d 6e 01
< 0001400 85 9c a9 00 85 b5 20 71 5e ca 10 cf 60 20 4d 63
---
> 0001260 fd fc fb a2 13 a9 00 85 9a bd 6e 01 f0 06 bd c2
> 0001300 01 20 f1 62 a9 fc 85 ec ad 0a 40 29 07 09 04 9d
> 0001320 c2 01 85 9a ad 0a 40 9d 39 01 ad 0a 40 c9 d0 b0
> 0001340 f9 c9 38 90 f5 9d 6e 01 a9 00 20 f1 62 ca 10 c5
> 0001360 60 85 b5 bd 6e 01 85 9c bd 39 01 85 9b 4c 71 5e
> 0001400 a5 a7 c9 28 90 02 a9 14 85 a7 4c 86 69 20 4d 63
86c86
< 0002520 00 a5 98 81 0d e6 0d 88 10 e7 60 5e a9 80 85 09
---
> 0002520 00 a5 98 81 0d e6 0d 88 10 e7 60 16 a9 80 85 09
115c115
< 0003440 ca 10 fb 20 86 69 20 7c 68 20 5e 67 20 21 69 a5
---
> 0003440 ca 10 fb 20 00 63 20 7c 68 20 5e 67 20 21 69 a5
bash-3.2$

Any Assembly programmers for 6502 that might have a clue what the above difference might be? Looks like 2 bits of logic and a couple values. Been a long time since I did any 6502 coding and I don't have an op code list or dissassembly program since the days of my C64!

================================
UPDATE
================================
I added a zip of the updated ROM image for all to enjoy -- I want to contribute to MAME but have no clue where or how to do it...
 
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Don't think it is. I have the chip that I extracted TB and Braze are checking it out now -- currently theory is its a bug fix for 800k scoring fix.

I'm sure I can post it somewhere for all to get that want it
 
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I'll have the code burned to chip in the next few days. I'll take the game up to 800k and see what happens. I'll report right back.
 
Here's a quick note I got from Scott Brasington after he took a quick look at the code -- so hopefully with a renewed interested we finally know the answer about this ROM revision

<QUOTE>
Scott Brasington to me

show details Jun 4 (7 days ago)

A quick (really quick look), there are quite a bit of changes because
of some code got inserted or deleted causing things to shift around
and the diff in the disasm then looks larger.

But I see changes in the areas of code that I think are for bonus
city calculations so that could be related to the 800K bug, although
I think that is different approach than how SMA did it. I also see
some changes in the code that fades away the "MISSILE COMMAND".
Not sure if that is because they needed to move code around to
make more space or because they actually changed things in how
that works where it flickers the colors and it rots away is what
I think that code does.

Good find. When I have more time I can look at it in detail and
do a better diff.

-Scott
</QUOTE>
 
OK, took delivery today of a new ROM chip that has 03e burned to it. So I slotted the ROM and took the game up to a million points. Looks like Scott was correct. It is a Bug fix for 800k.

I know this for sure as I dumped cities on the approach to 800k. Had just 3 cities as I passed 810k. Had just 4 on the next screen. The game also now awards bonus cities between 810 and a million points (it didn't before). Game still rolls over at a million points. Think thats it.

When I get a bit more time I'll take the game up to 255 screens and see if that bug has been fixed too. Might be a couple of weeks before I get around to that as it takes about 2 hours to do. It's great to still be finding stuff out about Missile Command after all this time, it's a game that just keeps giving!
 
PS

I attempted to zip the ROM and attach it to the original post so anyone can get it

I would like to contribute to MAME -- but 20 minutes or so garnered no easy way to do so
 
If anyone knows how/where to contribute this ROM to MAME -- please pull it down and do so I just can't figure out where and would like this updated ROM to be saved for all
 
Great research and response - I have come across a few of these and they are always an EPROM. I just stayed with the -02 version because it was the most common. I will start using this version when I need to add or replace that ROM.

As thorough as MAME seems to be, it's amazing that this was not covered in the past.

Bill
 
If anyone knows how/where to contribute this ROM to MAME -- please pull it down and do so I just can't figure out where and would like this updated ROM to be saved for all

When I've wanted to submit some roms, I emailed smittdogg over at MAMEworld. I'll send him an email when I get home (I'm at McDonalds right now ;) ) and show him this thread to see if they might be interested in it.
 
If anyone knows how/where to contribute this ROM to MAME -- please pull it down and do so I just can't figure out where and would like this updated ROM to be saved for all

To contribute it to MAME, send the file to [email protected]

In the email, write what you know about it. Some people really want to see their name in the release notes so why don't you submit it. Send the pic you have of the ROM as well. It may take a little while to add it so don't worry if it doesn't happen right away. It may be faster if you add it to the source as well, but isn't a requirement although someone else here might have a bit of fun adding it.
 
To contribute it to MAME, send the file to [email protected]

In the email, write what you know about it. Some people really want to see their name in the release notes so why don't you submit it. Send the pic you have of the ROM as well. It may take a little while to add it so don't worry if it doesn't happen right away. It may be faster if you add it to the source as well, but isn't a requirement although someone else here might have a bit of fun adding it.

Ok -- I'll give it a shot! Thanks
 
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