lr-mame MAME Settings Menu uses different SELECT button than Retroarch and other UI elements

[gritstub]

Batocera build version

43.1 2026/05/29 04:36

Your architecture

x86-64

Your Graphic Processor Unit(s) (GPU)

AMD Ryzen 7 5800H with Radeon Graphics

Issue description

Retroarch and Emulation Station uses the SOUTH button as OK, and the EAST button as Cancel.
When you open the MAME Settings menu with Input Setting, DIP Switches, etc. the EAST button is used for OK.

I'm using 8bitdo M30
https://github.com/batocera-linux/batocera.linux/blob/master/package/batocera/core/batocera-configgen/configgen/configgen/generators/libretro/libretroMAMEConfig.py

UI_SELECT is bound to "ENTER" and retroPad['a'] which is BUTTON2

Looking in the MAME -> Input Settings -> Input Assignments (general) -> User Interface

Item	Key
Show/Hide Menu	TAB or Joy 1 Select Joy 1 Y (default)
UI Select	ENTER or Joy 1 A (override)
UI Back	ESC or Joy 1 A (default, uses the same key as above)

Detailed reproduction steps

1. Open lr-mame
2. Open MAME Settings
3. Open Input Settings

Expected:

• Settings opens with SOUTH button, which is the OK for everywhere

Actual:

• Settings opens with EAST button

Details of any attempts to fix this yourself

No response

Details of any modifications you have made to Batocera.

None known.

Logs and data

Available on request

[gritstub]

The issue is also reproduced with 8bitdo SN30pro.

Retroarch Settings -> Controls -> Port 1 Controls

Direction	Item	Key
South	B Button (Down), Button 0, Key z	B
East	A Button (Right), Button 1, Key x	A
West	Y Button (Left), Button 2, Key a	Y
North	X Button (Top), Button 3, Key s	X

[gritstub]

Related to 7c518f6 ?

Where "a" was BUTTON1 instead of BUTTON2 ?