What does this mean ?

[PedroSilva]

Hi guys,

Hope you can clear this doubt I have:

In some games, on running there's a message "NO GOOD DUMP KNOWN", but still the game runs and it seems ok.

Can anyone tell exacly what does this message means ?

Thanks,

[Lilwolf]

One of the roms isn't dumped.  

Why it runs?  Some can be hacked around (color proms are a new thing to mame in the last few years... before that, all color roms where always hacked).

It also could be that you haven't got to the point where there is problems.

It could also be that the roms are dumped, but didn't match CRC's.  So there could be a pixel here or there which is switched...

But all in all... it usually means that it might run, but without perfect emulation.

[Tiger-Heli]

Hi guys,

Hope you can clear this doubt I have:

In some games, on running there's a message "NO GOOD DUMP KNOWN", but still the game runs and it seems ok.

Can anyone tell exacly what does this message means ?

Thanks,

I'm no expert, but I assume it means when the MAME devs dumped the ROMS from the game board, there was another rom on the board (or something somewhere said there should be another rom on the board), but it was missing or they couldn't read the code from it.

The game works either b/c the function of the ROM had nothing to do with gameplay, or b/c when they developed the driver the MAME devs worked around what that ROM was supposed to do to make the game playable.

You see this often with games with color PROMS where the color Rom chip is often way apart from the other ROM chips and looks about like any other IC chip on the board.

[screaming]

  A 'dump' is when someone 'downloads' the data from the ROM chip onto thier computer. If something happens in this process, whether it be a bad dumper mechanism, bad ROM chip, a blip in the saving of the ROM - anything - it could cause problems with the dump and therefore make it a 'bad' dump. Even if the game is playable, there might be problems related to incorrect data in the dump.

  I'm not sure how common bad dumps are, but I know that sometimes it can take a couple tries and a lot of testing before you've vverified that it's a good dump.

  One of the problem that the MAME devs face is that it's pretty tough to get thier hands on the hardware for some of these games. They sometimes don't get a lot of chances to get the data off those boards (hardware).

/Steve

[PedroSilva]

Well ... the example is, for instance, the 64street ... on the status provided in the gamelist it is suposed to be "perfect" ...

[Tiger-Heli]

Well ... the example is, for instance, the 64street ... on the status provided in the gamelist it is suposed to be "perfect" ...

Emulation is perfect based on the ROM that they used (which they think needs to be re-dumped).  Perfect to MAME devs means "We don't have any more work to do on this at this time", not necessarily "This plays with absolutely no problems".

[PedroSilva]

Well ... the example is, for instance, the 64street ... on the status provided in the gamelist it is suposed to be "perfect" ...

Emulation is perfect based on the ROM that they used (which they think needs to be re-dumped).  Perfect to MAME devs means "We don't have any more work to do on this at this time", not necessarily "This plays with absolutely no problems".

Attention:
There is "No GOOD DUMP KNOWN" and there is "ROM NEEDS REDUMP" ...
It's not the same thing ... at least I "think" it's not the same thing ...  and it seems that there are diferent opinions on the subject ...  

Maybe it would be nice to have some type of "Mame error messages" and their meanings ?

Does it exists already ? If yes where can it be found ?

[Tiger-Heli]

Well ... the example is, for instance, the 64street ... on the status provided in the gamelist it is suposed to be "perfect" ...

Emulation is perfect based on the ROM that they used (which they think needs to be re-dumped).  Perfect to MAME devs means "We don't have any more work to do on this at this time", not necessarily "This plays with absolutely no problems".

Attention:
There is "No GOOD DUMP KNOWN" and there is "ROM NEEDS REDUMP" ...
It's not the same thing ... at least I "think" it's not the same thing ...  and it seems that there are diferent opinions on the subject ...  

Maybe it would be nice to have some type of "Mame error messages" and their meanings ?

Does it exists already ? If yes where can it be found ?

No GOOD DUMP KNOWN - There's supposed to be this other rom that the game needs, but it was encased in epoxy, missing from the board we got, and we don't have it.

ROM NEEDS REDUMP - We dumped part of the ROM, but it had errors and we're not sure whether it was correct or not, but dumping it again did not help.

I don't think there is much difference in gameplay, but I'm not sure about any of this.