The picoZ80 board drops directly into a legacy Z80 DIP‑40 socket, swapping the original 8‑bit CPU for a dual‑core RP2350B Cortex‑M33 that can run up to 300 MHz. Its programmable I/O state machines recreate every Z80 bus cycle with cycle‑accurate timing, while extra SRAM, 8 MB PSRAM and 16 MB flash give the host far more memory and storage options and supports rapid application loading from SD card.

An ESP32 co‑processor adds Wi‑Fi, Bluetooth and an SD‑card reader, exposing a browser‑based config.json interface that lets users remap ROM images, define virtual peripherals, or enable floppy‑disk and QuickDisk emulation without recompiling firmware. Personas for Sharp MZ‑700, MZ‑80A/B and other Z80 machines are already functional, and configuration changes apply instantly.

All logic runs at 3.3 V with level‑shifting for the host’s 5 V bus, and the board includes a USB hub for firmware updates via a dual‑partition OTA scheme. KiCad‑generated schematics and Gerbers are publicly available, enabling hobbyists to assemble revisions from v2.0 through v2.5 on a six‑layer PCB. Its compact footprint fits within original case, preserving the machine’s aesthetic.