MAME and CHD

[eugenewright]

I have downloaded the full set 0.240 non merged for mame, I can also download the chd which however I see that they are 500+giga.Are they different games? Does it make sense to download all these files?More I ask because I see that chd is for merged full sets while I have non merged.

[mhoes]

I have downloaded the full set 0.240 non merged for mame, I can also download the chd which however I see that they are 500+giga.Are they different games? Does it make sense to download all these files?More I ask because I see that chd is for merged full sets while I have non merged.

Hi,

First and foremost - and I realize this piece of information is reaching you a little late - but: in general, you are advised to use the latest version of MAME (and the romsets that go with that version), since that will have the most bug fixes and latest/most/best support for all the different systems mame emulates. The current version is 0.269, and is available over here : https://www.mamedev.org/ .

But to answer your first question : the CHD's are not different games/machines/systems, they are additions to some specific systems. Almost all systems I know of have romsets (which correspond to the ROMs the real machines have). But some systems also had additional local storage, for example a hard disk (HDD) or laserdisc, etc. For those games, there is a need for both the romsets and the CHD (which represents the local storage, HDD etc.). I guess I would not download all the CHD's up front (as the entire collection is indeed quite large), but rather just start playing games, and then if/when you discover that any given game also needs a CHD, download that specific one for that particular system.

As for your second question: I honestly do not know if you can mix merged CHD sets with non merged romsets, as I never tried that myself. If I would have to guess I would assume that you can mix them, but you know what happens when we assUme. Again, I would download a single particular CHD from the entire collection, and see if it works or not, before you start downloading entire collections.