185 rom set versions - non-merged - noon question

[YouknowStuIlltellya]

I understand that non-merged contain all versions in one zip.

Im in a  non-merged 185 full rom set list of zips, as I am only interested in pulling the games that I want vs the thousands contained within.

For Atari7800, many of the games have regular version zip file and then one ending in u.  EG - digdug and then digdugu

The digdug ZIP has only the digdugu BIN file.

The digdugu ZIP file is about double the file size and has digdug and digdugu BIN files. 

I assume the digdugu ZIP is the one to grab? And if so, why does the digdug ZIP only have the digdugu BIN file?

I would assume the digdug ZIP would only have the digdug BIN file vs the digdugu bin file if it was an option to grab the non-updated version.  Or maybe the u vs non-u has nothing to do w/ updated. 

How could digdug ZIP even work on its own if it only has the digdugu BIN file. 

Thanks in advance.

   

[nexusmtz]

a7800 software would have cartridges within the zips.
a7800 is for NTSC, a7800p is for PAL.

The software list (mame64 -listsoftware a7800) for digdug is:

Code: [Select]

<software name="digdugu" cloneof="digdug">
<description>Dig Dug (NTSC)</description>
<year>1984</year>
<publisher>Atari / Namco</publisher>
<info name="serial" value="CX7803"/>
<part name="cart" interface="a7800_cart">
<feature name="slot" value="a78_rom" />
<feature name="compatibility" value="NTSC" />
<dataarea name="rom" size="16384">
<rom name="digdugp.bin" size="16384" crc="50cb13f3" sha1="19cee8dc40fabd7022bedc27e4896c09e3cadfdd"/>
</dataarea>
</part>
</software>
<software name="digdug">
<description>Dig Dug (PAL)</description>
<year>1984</year>
<publisher>Atari / Namco</publisher>
<info name="serial" value="CX7803"/>
<part name="cart" interface="a7800_cart">
<feature name="slot" value="a78_rom" />
<feature name="compatibility" value="PAL" />
<dataarea name="rom" size="32768">
<rom name="digdugeu.bin" size="32768" crc="efab7077" sha1="ce05d3270b0e0d36d80a4f0731d0173cb5921bce"/>
</dataarea>
</part>
</software>

So the US (NTSC) version of digdug (digdugu) should have digdugp.bin at a size of 16KB
and the Europe (PAL) version of digdug (digdug) should have digdugeu.bin at a size of 32KB

I don't know where your files came from, but the software zips don't appear to be for MAME 185.