Start button and key not working with ST-V game

[thingsiplay]

What's the full name of the game (including region) ?

Rom directly taken from MAME, as it is an ST-V arcade game.

cotton2.zip: Cotton 2 (JUET 970902 V1.000) - MAME machine

What's your frontend ? (standalone, libretro, ...) ?

Libretro

$ retroarch --version
RetroArch - Frontend for libretro
Version: 1.18.0 (Git 06fa5325f8) Mar 22 2024
Compiler: GCC (13.2.1) 64-bit

What's your OS ? (windows, linux, OSX, ...) ?

Linux

OS: EndeavourOS x86_64
Kernel: 6.8.5-zen1-1-zen
DE: KDE Plasma 6.0.3
WM: KWin (Wayland)

What's your hardware ? (CPU, GPU, ...) ?

AMD Ryzen 7700X + AMD RX 7600

CPU: AMD Ryzen 7 7700X (16) @ 5,57 GHz
GPU 1: AMD Radeon RX 7600 (RADV NAVI33) [Discrete] Mesa 24.0.5-arch1.1
GPU 2: AMD Radeon Graphics (RADV RAPHAEL_MENDOCINO) [Integrated] Mesa 24.0.5-arch1.1
Memory: 3,71 GiB / 30,50 GiB (12%)

What's the storage type of the game (official cd, burned cd or cd image) ?

It's a MAME Rom in ZIP archive format, as it is an arcade game.

Type = zip
Date      Time    Attr         Size   Compressed  Name
------------------- ----- ------------ ------------  ------------------------
1996-12-24 23:32:00 .....      4194304      1639444  mpr20116.1
1996-12-24 23:32:00 .....      4194304      2275311  mpr20117.2
1996-12-24 23:32:00 .....      4194304      2575198  mpr20118.3
1996-12-24 23:32:00 .....      4194304      2056748  mpr20119.4
1996-12-24 23:32:00 .....      4194304      2018675  mpr20120.5
1996-12-24 23:32:00 .....      4194304      2170834  mpr20121.6
1996-12-24 23:32:00 .....      2097152       834612  mpr20122.7
1996-12-24 23:32:00 .....      4194304      1620739  mpr20123.8
------------------- ----- ------------ ------------  ------------------------

Are you using any setting different from default ? If so, precise

Kronos: Core Options of Kronos itself are all at default. I tested with ST-V Favorite Region set to "US", but also tested the default setting of "EU" as well.

RetroArch: Some settings of Libretro/RetroArch itself are customized and I don't know what the defaults actually are and if any setting is relevant.

Did this game work previously ? Do you remember when ? Is it happening with other games ?

I'm new to Kronos and it's the first time I tried this game. As noted in the below description, Cotton 2 native Saturn version works normal and I can start game with Start button. Only the ST-V arcade based game from MAME ignores the Start button/key, but otherwise loads fine into title screen.

If applicable, provide error messages, logs, screenshots, or whatever additional information that could help debugging this

Kronos (core) installed and Cotton 2 game rom from MAME cotton2.zip loads fine, music plays, title screen shows up and I can insert coins. But the Start button does not work, even though its setup. Rom works fine in MAME, controller works fine with other cores and when I try Kronos with a different controller results in same issue. So it seems to be controller independent. Sidenote, the keyboard key for Start button does not work too, even if I explicitly set a specific key for it in the Controls menu of RetroArch.

I tried to load Cotton 2 (Japan).chd as a native Saturn game in Kronos; and it works fine with Start button and I can play the game. Just the ST-V arcade game does not work (at least the Start button).

I found this closed issue for Yabause (which Kronos is based on) without much information or resolution that might be relevant: https://github.com/libretro/yabause/issues/300 1 Other users from RetroArch forum reported same issue of Start button not reacting in Kronos core as well.

I’m on a Linux system. RetroArch 1.18 and all files updated, core Kronos just installed and Bios files present.

If I run Kronos with “ST-V Service/Test Buttons” enabled and go into the test menu to check the input device, then the Start button is recognized even with the ST-V game is loaded in. It's recognized in the input test menu, not in the actual game.

Log generated with retroarch --verbose 2> retroarch.log in the terminal attached as a text file.

retroarch.log