How to remap controls for the standalone-rice N64 emulator on the PowKiddy RGB20S

I've just answered this query from a reader of our PowKiddy RGB20S User Guide, so I thought I'd post it here in case it might help someone else.

To remap the controls for the standalone-rice N64 emulator, so that they match the commonly-used layout, you need to edit the file /opt/mupen64plus/InputAutoCfg.ini on the root partition of the SD card. Find the [GO-Super Gamepad] and edit it to read as follows:

[GO-Super Gamepad]
plugged = True
mouse = False
AnalogDeadzone = 0,0
AnalogPeak = 32768,32768
DPad U = button(8)
DPad D = button(9)
DPad R = button(11)
DPad L = button(10)
Start = button(13)
Z Trig = button(4)
# Swap A and B
B Button = button(0)
A Button = button(1)
C Button U = axis(3-)
C Button D = axis(3+)
C Button R = axis(2+)
C Button L = axis(2-)
R Trig = button(5)
L Trig = button(6)
Mempak switch =
Rumblepak switch =
# Analog axis configuration mappings
X Axis = axis(0-,0+)
Y Axis = axis(1-,1+)

The difficult part is getting access to the root partition. It uses a Linux file system that Windows can't read without special software (do not let Windows format any of the partitions on the SD card). If you have a USB-C adapter and a WiFi dongle, you can connect your RGB20S to WiFi, enable SSH, and access the files over the network using a programme called WinSCP.

This remapping method also works with an Anbernic RG351MP when it's running ArkOS.