To develop, test and connect the board: emulator, keyboard, BBC Micro layer, Wi-Fi modem, debugging.
Reference emulator of the Neo6502, to test programs without the board: cycle-stepped, 65C02 core validated on 2.54 million test cases, API linked to the firmware code, running without a display, captures, save states.
Keyboard driver in 65C02 assembly (ca65): events (scancode, modifiers), base / Shift / AltGr / Ctrl mapping compiled from a .kmap (us, fr) by neokbd, a Go tool with a simulator.
BBC Micro MOS layer → Neo6502 API (OSWRCH, OSBYTE, OSWORD, OSCLI…). The reload BBC emulator boots MOS 1.20, BASIC 2, DFS, and starts Spellbinder.
C firmware that turns a Raspberry Pi Pico W into a Wi-Fi modem for the Neo6502: ESP8266 AT dialect (prophet.neo and neo-networking work unmodified), Hayes modem, USB CDC and UART on UEXT, TLS terminated in the Pico W with a verified certificate. Validated on the board. Source code →
A Pico W flashed with debugprobe, three wires (GP2, GP3, GND) and OpenOCD: read the running RP2040's memory, even with a stuck firmware.