Firmware v1.2

Socket detection. The Pico can now tell which of its chip-select lines lead to a socket, so the app sets its socket count by itself.

New

• S_CMD_Q_CS_WIRED (0x24): returns a bitmap of the CS lines that have a pull-up resistor. Each CS pin is briefly read as an input against the RP2040's internal pull-down (50–80 kΩ); a line with an external 10 kΩ pull-up to 3V3 reads high, an open one low. The pin is set high again before it drives, so no chip sees a select glitch.

Hardware (optional, recommended)

• Add a 10 kΩ resistor from each socket's /CS line to 3V3 (Pico pin 36). Values from 4.7 kΩ to 10 kΩ work; 22 kΩ or more is too weak. Keep the resistors' common side on 3V3: tied only to each other they seem to work while the Pico runs, but nothing holds the chips deselected while it starts or resets.
• Boards without the resistors keep working: the app then uses the socket count set by hand.

In the app

• settings → sockets → auto (the default) shows exactly the wired sockets; a socket between wired ones without a resistor shows as not wired and is skipped. Without pull-ups the app falls back to a manual count; detect again re-checks.

Compatibility

• Works with older versions of the app (they don't ask for the wiring). Everything from 1.1 stays the same.

What's Changed

• Socket settings by @Waffelo in #4
• Don't freeze on a Pico that doesn't answer by @Waffelo in #5
• Cs detect by @Waffelo in #6

Full Changelog: fw-v1.1...fw-v1.2