W78E58B/W78E058B is a W78E58B/W78E058B series 8-bit microcontroller with 32KB of programmable flash, 32KB of RAM, 8 16-bit I/O ports, two 16-bit timers, a 16-bit serial communication interface, an 8-bit serial communication interface, a 16-bit parallel communication interface and an 8-bit parallel communication interface, and a watchdog, programmable clock multiplier, programmable power-down voltage detection, programmable power management module and other functions.
The W78E058B is an 8‑bit microcontroller with in‑system programmable Flash EPROM, 32 KB main ROM, 4 KB auxiliary ROM, and 512 B on‑chip RAM. It offers four 8‑bit bi‑directional I/O ports, a 4‑bit programmable port, three 16‑bit timers/counters, a full‑duplex serial port, and built‑in power‑management features.
The document includes a general description, feature list, pin configurations and descriptions, functional blocks, timing waveforms, typical application circuits, programming examples, electrical characteristics, and revision history. It also details power‑down and idle modes, EMI reduction, and security features.
| CPU architecture | 8‑bit |
|---|---|
| Main ROM size | 32 KB |
| Auxiliary ROM size | 4 KB |
| On‑chip RAM | 512 bytes (256 B AUX‑RAM selectable) |
| I/O ports | Four 8‑bit bi‑directional ports and one 4‑bit programmable port |
| Additional I/O port | One 4‑bit multipurpose programmable port |
| Timers/Counters | Three 16‑bit timer/counters |
| Serial interface | One full‑duplex serial port |
| Interrupt sources | Eight sources, two‑level interrupt capability |
| Power‑management modes | Idle mode and power‑down mode |
The main ROM is 32 KB.
It provides four 8‑bit bi‑directional ports and one 4‑bit programmable port.
The microcontroller supports idle mode and power‑down mode, both selectable by software.
Set bit 4 in the CHPCON register to enable the AUX‑RAM.