MAMEWorld Forums - EmuChat

Okay, I'm probably completely stupid, in addition to being a relative noob, but I could really use some help. I've spent close to 12 hours trying to figure out how to use MAME/MESS without any luck. Let me clarify that. I've been using MAME to run arcade game roms for a good year. I am trying to expand my library to include some games I used to play (and legitimately own) for the Atari 800. I think I had a passable understanding of MAME a year ago, but I've been using the Maximus Arcade frontend since then, and I'm not sure I remember everything. I have searched and searched for explanations and help, but haven't found anything useful. Everything I have found is either totally basic and doesn't tell me enough, or written for someone who already understands the system well.

Here's where I am:
It is my understanding that the program formerly known as MESS has been incorporated into MAME. I have MAME64 0.156 installed and working fine on both my laptop and my cab. If I understand correctly, in order to emulate a computer (such as an Atari 800), I need first to put the system roms in the "Roms" folder for MAME. So I downloaded a800.zip and dropped it in D:\Console\Mame\Roms. Then, if I understand correctly, I can just type "Mame64 a800" to simply open the atari 800 emulator in "Memo".

When I type "Mame64 a800", I get "Unknown system 'a800'" and a list of games that begin with "a". If my somewhat spotty memory serves me correctly, there is a file somewhere that contains a list of ALL the available MAME roms, the specifics of each rom, and a name you can use to launch that rom, and I am guessing the Atari 800 roms aren't in that file. Am I correct so far?

It is also my understanding that there are game lists that contain all the roms available for each system and the specifics for each rom, as well as a name you can use to launch the rom, and that these files go in the "Hash" folder. I found a800.xml, which appears to contain the info for a whole lot of Atari 8-bit cartridges? and a800_flop, which appears to contain the info for a single game executable. I downloaded both and installed them in the HASH directory, but I can't see that there is info for the game "Hacker" or the game "Fooblitzky" in either file. I have seen numerous posts about what sound like complete a800_flop.xml file lists, but I can't find one anywhere. They all just contain "Jumpman." In the documentation, I saw how to add games to the a800_flop.xml, so I thought I would just do that, but I have no idea about the technical numbers like the checksum for "Hacker" or "Fooblitzky," and I have searched everywhere and cannot seem to find that information, either.

The funny thing is, I downloaded and installed MESSUI64, and I can launch that program, choose Atari 800 (NTSC), click the "Media View" tab, mount the Fooblitzky.zip file as a floppy, then click the SW Files and Fooblitzky.atr appears, and I can run it. So the problem obviously isn't my computer, it's just my lack of knowledge. Can someone please help me understand all this? Sorry to be so lengthy, but I figured the more info you have, the more likely I am to get the right help.

Jim