The W78L54 microcontroller is an 8-bit microcontroller that offers a wider frequency and supply voltage range compared to most other 8-bit microcontrollers on the market. It is compatible with the industry standard 80C54 microcontroller series. The W78L54 features four 8-bit bidirectional parallel ports, an additional 4-bit bit-addressable I/O port (Port 4), two extra external interrupts (INT2, INT3), three 16-bit timer/counters, a watchdog timer, and a serial port. These peripherals are supported by an eight-source, two-level interrupt capability. The microcontroller has 256 bytes of RAM and a 16K byte mask ROM for application programs. It also offers two power reduction modes: idle mode and power-down mode, both of which can be selected using software. The idle mode turns off the processor clock but allows peripheral operation, while the power-down mode stops the crystal oscillator for minimal power consumption. The external clock can be stopped at any time and in any state without affecting the processor.
The W78L54 microcontroller supplies a wide frequency and supply voltage range and is compatible with the industry‑standard 80C54 series. It includes four 8‑bit bidirectional ports, an extra 4‑bit bit‑addressable I/O port, three 16‑bit timer/counters, a full‑duplex serial port and eight‑source, two‑level interrupt capability.
Key features include a fully static design, supply voltage of 1.8 V to 5.5 V, DC‑24 MHz operation, 256 bytes of on‑chip RAM, 16 KB mask ROM, 64 KB program and data memory spaces, two power‑reduction modes (idle and power‑down), watchdog timer, EMI reduction mode and code protection. The device is offered in DIP‑40, PLCC‑44 and QFP‑44 packages.
| Supply voltage | 1.8 V to 5.5 V |
|---|---|
| Maximum operating frequency | 24 MHz |
| On‑chip RAM | 256 bytes |
| Mask ROM | 16 KB |
| Program memory address space | 64 KB |
| Data memory address space | 64 KB |
| Number of 8‑bit ports | 4 |
| Extra I/O port | 4‑bit bit‑addressable |
| Timer/counters | Three 16‑bit |
| Serial port | Full‑duplex |
| External interrupts | INT2, INT3 |
It operates from 1.8 V to 5.5 V.
The microcontroller provides 256 bytes of on‑chip scratchpad RAM.
It is available in DIP‑40 (W78L54‑24), PLCC‑44 (W78L54P‑24) and QFP‑44 (W78L54F‑24) packages.
Two additional external interrupts, INT2 and INT3, are provided.