This manual introduces the features and usage methods of µPD78F9221/22/21A/22A/21A2/22A2 8-bit single-chip microcontrollers.
This manual is intended for engineers who need to understand the functions of the 78K0S/KA1+ microcontroller family and develop application systems and programs. It covers the target sub‑series devices (UPD78F9221, UPD78F9222, and their variants) and explains how to read registers, use the instruction set, and access related development tools.
Key sections include pin function tables, CPU architecture details, electrical specifications, flash‑memory programming tools, and revision history. The document also provides handling precautions such as ESD protection, unused‑pin treatment, and recommended power‑on/off sequences.