How to run Atari 7800 on lr-mess ?

[Widge]

Pi Model : 4B
Power Supply used: Authentic Raspberry Pi 3A power supply
RetroPie Version Used : 4.8
Built From: standard RetroPie - from scratch and updated over time
USB Devices connected: Sinden Lightguns
Controller used: 8bitdo SN30pro, bluetooth

I have been led to understand that lr-mess is able to run Atari 7800 but I have been unable to find any documentation or guidance on the topic.

I am aware that lr-prosystem is typically the core of choice for 7800, but it does not have lightgun support, and I am keen to run lightgun games in particular.

The retropie docs don't say much on the topic and the reddit post linked to in the Retropie docs mess page no longer contains the information.

I have tried placing a bios file in the roms folder as is advised in the docs to no avail. I have also tried placing the bios in a the roms/atari7800 folder, but no matter what I try with each attempt to run a .a78 rom, lr-mess loads to nothing but a grey screen. Ihave made sure that my core options are set as described on the docs page, with CLI, Software lists and auto launching enabled.

The only element of success I have had was to attempt to launch the bios zip itself in mess, which launches the core to a striped screen. I have then been able to use the tab menu to manually load a .a78 file, but often these have graphical glitches. I'm not sure this is the right way to do things though.

In short, I have no idea what I'm doing with lr-mess. I don't know if I have the correct type of roms, or the correct bios or where to even place the files.

I'm quite savvy with retropie in general having had a few years of regular use under my belt, but lr-mess is unlike most of the other cores I've used. Any advice would be welcome and appreciated. If I'm barking up the wrong tree however, please feel free to let me know!

Thanks.

[Folly]

@Widge

You should look at our project over here :
https://retropie.org.uk/forum/topic/29682/development-of-module-script-generator-for-lr-mess-lr-mame-and-mame-standalone

I would advice you to use add-ext-repos.sh so every script module is downloaded into the ext directory (including add-mamedev-systems.sh) :
https://retropie.org.uk/forum/topic/25576/new-scriptmodules-lr-vice-xvic-gsplus-proper-lr-mess-integration/543

Then goto config/add-mamedev-systems and install a7800 and a7800p .
It will be recognised, see here :
https://retropie.org.uk/forum/topic/29682/development-of-module-script-generator-for-lr-mess-lr-mame-and-mame-standalone/1043

You should find the latest mame bios ( in mame-merged ) a7800.zip or .7z and place it in BIOS/mame .
Find the latest mame softlist ( in mame-sl ) file, I think, it is also called a7800.zip and extract this in your roms/atari7800 directory.

I just tried asteroid.zip and should load with the lr-mess-a7800-basename or the mame-a7800-basename loader.

Note that not all games will work on a7800 !
If it doesn't it's probably a PAL game, not NTSC, for that we use a7800p.
Tested xevious and dkonjr and they work with a7800p .

[Widge]

Thanks @Folly . This looks like it might be just what I need. I'll check it out.

[Widge]

@Folly. Thanks again. I was able to get Atari7800 running in mess fairly quickly with your advice. Although add_mame-dev-systems.sh wasn't included in add-ex-repos.sh but I managed to add it by using the same wget command, but replacing the .sh filename.

Before long I managed to get a bunch of games running. However, I was not able to get mess to acknowledge lightgun input for these games. Do you know if there's an extra step to enable it, or if the 7800 drivers haven't accounted for lightgun input yet?

[Folly]

@Widge said in How to run Atari 7800 on lr-mess ?:

@Folly. Thanks again. I was able to get Atari7800 running in mess fairly quickly with your advice.

Nice to hear that you have worked it out so quikly ;-)

Although add_mame-dev-systems.sh wasn't included in add-ex-repos.sh

It isn't but selecting FollyMaddy in that module-script will download all my module-scripts, including add-memedev-systems.sh .

but I managed to add it by using the same wget command, but replacing the .sh filename.

That is also a solution.
It's placed now probably in /home/pi/RetroPie-Setup/scriptmodules/supplementary
And it will generate module-scripts in /home/pi/RetroPie-Setup/scriptmodules/libretrocores.

No problem, if you want to know why I advised it then you can read it here :
https://retropie.org.uk/forum/topic/29682/development-of-module-script-generator-for-lr-mess-lr-mame-and-mame-standalone/1163

Before long I managed to get a bunch of games running. However, I was not able to get mess to acknowledge lightgun input for these games. Do you know if there's an extra step to enable it, or if the 7800 drivers haven't accounted for lightgun input yet?

I probably can't help you with that, but :

• Have you tried if setting up is possible in RetroArch ?
• Have you tried the mame gui using tab in lr-mess ?
• Have you tried just using mame standalone and mame gui using tab ?

@AdamBeGood
You have some lightgun experience.
Can you help ?

[Widge]

@Folly said in How to run Atari 7800 on lr-mess ?:

Have you tried if setting up is possible in RetroArch ?

I know the lightguns work in Retrorarch I use them succesfully in many cores including various iterations of mame. I'm even able to use them for a few tiger plug-n-play games in lr-mess (swclone, pballpup and tmntmutm).

Have you tried the mame gui using tab in lr-mess ?

When I press tab in the game I can access the input settings and these seem to be only basic digital settings across the board for all the A7800 games I've tried. The first picture below is of the input settings from the tab menu when accessed in Crossbow, the second picture is of the input settings from Mission Paintball Powered Up, which is a lightgun game that I have been able to play in lr-mess for some time and it shows analog inputs available - in this case labelled lightgun.

Many games I play in lr-mame have various types of analog control options including, AD-Stick, Paddle, Dial, etc. all can be used with the lightgun, but the lightgun games in A7800 aren't showing an analog input available, which is why I wonder if the driver isn't equipped for it. I'm confident that at least some of the roms I'm using are for the lightgun variants of the games - crossbow for example has a selection screen to choose between gun/stick.

Have you tried just using mame standalone and mame gui using tab ?

If you mean lr-mame then yes, I have and do use lr-mame for lightgun games, but the a7800 roms don't run in it. If you mean regular (non-lr) mame, then no. In order to use the sinden lightgun, a border needs to be on screen for the gun's camera to reference and in RetroPie on the raspberry pi the only way to do that is with retroarch overlays.

I appreciate the assistance. Thank you

[Folly]

@Widge

Do you have a sinden lightgun ?
Can you paste the pictures in the post, the links do not work.

[Widge]

@Folly
Yes, it is a Sinden Lightgun.
I have edited the post to include the images rather than links to them.

[Folly]

@Widge

The sinden lightgun works, to my knowledge, just like a mouse.
So I did some tests with my mouse as surrogate lightgun.

I had the same conclusion.

I tried to map my mouse to the dpad which seems work partly, but is not a solution because only 1 side reacts.

Configuring it somehow in RetroArch could be a possible solution but, for now, I have no idea how to accomplish that.

[Widge]

Thanks for taking the time to look into it.

[Folly]

@Widge

That's ok.

We will have to wait until somebody else has figured it out.