Your console

Romule talks to an Android handheld through adb. It was built against an AYN Thor running the Eden emulator, but the device and the emulator are profiles, not hard-coded paths.

Pairing over Wi-Fi

The first-start assistant asks first how the console is connected — with or without a cable — and shows only the matching path. The settings hold the same step-by-step assistant. In short:

1. On the console — Settings → System → Developer options → Wireless debugging, switch it on. No developer options? Settings → About phone, tap Build number seven times.
2. On the console — in the Wireless debugging screen, tap Pair device with pairing code. Leave the window open: the code expires when it closes. It shows a six-digit code and an address like 192.168.1.42:37105.
3. In Romule — enter that address and that code, then confirm the pairing. Romule then connects on its own, starting with that very address: on a good many devices the pairing port and the connection port are the same number. Failing that, it tries a link left by a previous session, what the consoles announce over mDNS, then port 5555.
4. On the console (only if none of them worked) — close the code window. The Wireless debugging screen behind it shows its own “IP address and Port” line, and it is not the same one: the pairing port is used only once. Copy that one into Romule, then Connect the console.

Once connected, the console is recognised on its own from then on.

Once connected, the panel asks nothing more: it shows what the console answered — its name, its address, its Android version, its battery level, how long the link has held. None of that can appear unless the console replied, which makes it worth more than a plain “connected”.

Under Docker, step 4 is the rule

The console announces its connection port over mDNS, and multicast does not cross the Docker bridge. From a container Romule therefore cannot guess it: it has to be read off the console's screen. On a direct install discovery works, and step 4 almost never appears.

Why two ports?

Android's wireless debugging exposes two services, each on its own random port:

• _adb-tls-pairing exists only while the code window is on screen. It exchanges a TLS certificate, checked against the six-digit code, and then closes;
• _adb-tls-connect is the adb daemon itself. It stays open for as long as wireless debugging does, and accepts only the certificates obtained by pairing.

Both ports come from the same ephemeral pool and are handed out moments apart, so they are often neighbours — which is what Romule uses to find the second one without asking for it.

Two addresses, two ports

This is where it goes wrong. The code window gives a pairing port, good for one use; the Wireless debugging screen gives another one, for the connection. Entering the first at step 4 fails without explaining itself.

Wi-Fi is slower

Two to five times slower than USB for large transfers. Fine for a few games, noticeable for a full library.

When folder names say nothing

Recognising gba or PS1 works on a console that names them that way, and finds nothing at all on one filing games under Nintendo - Game Boy Advance or psx-eur. So Romule looks at the contents too: a folder holding game files IS a platform folder, whatever it is called.

Finding the root does not require knowing WHICH platform — just as well, since .cue and .iso are claimed by every disc console at once.

And when none of that works, both the wizard and the settings let you browse the console and point at the folder by hand.

USB

Plug the console in with debugging enabled and press Detect. Under Docker, USB requires devices: - /dev/bus/usb:/dev/bus/usb and Linux — see Installation.

The games folder

Romule detects it, and shows it once connected:

/storage/emulated/0/Switch

Change it in Settings → Your console if your emulator keeps games elsewhere.

The ROMs folder — the parent of every other platform, each in its own subfolder — is found the same way, by recognising folder names: gba, snes, but also PS1 for the PlayStation or Sega for the Mega Drive. The folder holding the most of them wins, and at least two are needed: a lone Wii folder proves nothing.

That is what saves typing the path. Deriving it from the Switch folder — its parent — was right only on consoles that keep everything side by side; elsewhere every platform counted zero, and the library's selector stopped showing their numbers.

A platform Romule does not know

Twenty-three platforms are recognised out of the box, and the list is not a limit. Settings → Your console → Add a platform… takes three things:

Field	Example	What it is for
Display name	Neo Geo	What you will see in the platform selector
Folder on the console	NeoGeo	A subfolder of the ROMs folder above
Extensions	zip, neo	What counts as a game for that platform

That is enough for the platform to be scanned, filtered, counted and pushed like any other. It is also the answer when a console is known but you keep it in a folder Romule would not guess — declare it under the name you actually use.

The added platforms are stored as systemes_perso in the settings file, and travel with your backups.

What it does not do

Declaring a platform does not teach Romule to read the inside of its files. Switch is the only one it opens: title IDs, base/update/DLC relationships and missing updates come from parsing the container. Every other platform — built-in or added — is identified by folder and extension.

Layout on the console

Switch files are sorted into GAMES, UPDATE and DLC. The type comes from the file's contents when Romule knows it, not from its name — a name lies often enough: a truncated title ID, a missing one, or a file announcing a base game that is really an update.

What is already on it

List the games on the console reports what it holds and how many of those are missing from your library, so you do not re-import what is already there.

Adb is not installed

Romule says so and gives the command for your platform. Nothing else stops working: the library, the cover art and the inventory do not need a console.