EM78451 is an 8-bit microprocessor produced by EMCT. It has the characteristics of low power consumption, high speed, and high integration, and can be used for wired communication.
The EM78451 is an 8‑bit microprocessor built with low‑power, high‑speed CMOS technology and offered in a mask‑ROM version. It includes a serial peripheral interface (SPI) and an easy‑to‑use RS‑232 interface, making it suitable for wired communication and in‑circuit emulation.
Key features include a wide operating voltage range, multiple clock modes, low power consumption, on‑chip ROM and RAM, several I/O ports, built‑in watchdog timer, and various package options. The document provides detailed pin assignments, functional block diagrams, and register descriptions for developers.
| Operating voltage range | 2.3 V ~ 5.5 V |
|---|---|
| Operating temperature range | 0 °C ~ 70 °C |
| Crystal mode frequency | DC ~ 20 MHz @5 V, DC ~ 8 MHz @3 V, DC ~ 4 MHz @2.3 V |
| RC mode frequency | DC ~ 4 MHz (all voltages) |
| Power consumption (active) | < 3 mA at 5 V/4 MHz |
| On‑chip ROM size | 4 K × 13 bits |
| Bi‑directional I/O ports | 5 ports (35 V/O pins) |
| Package types | 40‑pin DIP (EM78451AP) or 44‑pin QFP (EM78451AQ) |
The device operates from 2.3 V to 5.5 V.
It provides five bi‑directional I/O ports.
The on‑chip ROM is 4 K × 13 bits.