The 87C654 is a single-chip 8-bit microcontroller manufactured by Philips Semiconductors. It is a derivative of the 80C51 microcontroller family and has been enhanced with additional features and capabilities. The 87C654 contains a 16k-byte EPROM, a 256-byte RAM, four 8-bit I/O ports, two 16-bit timers/counters, a multi-source, two-priority-level, nested interrupt structure, an I2C interface, a UART interface, and an on-chip oscillator and timing circuits. Additionally, the 87C654 can be expanded using standard TTL-compatible memories and logic.
This document is a product specification and data handbook for the Philips 87C654, a CMOS single-chip 8-bit microcontroller. It describes the device as an advanced derivative of the 80C51 family, featuring a non-volatile 16k x 8 EPROM, 256 x 8 RAM, four 8-bit I/O ports, two 16-bit timer/event counters, and an I²C interface. The microcontroller supports architectural enhancements for general control systems and includes power control modes such as Idle and Power-down.
| Memory (ROM) | 16k x 8 EPROM, expandable externally to 64k bytes |
|---|---|
| Memory (RAM) | 256 x 8 read/write data memory, expandable externally to 64k bytes |
| I/O Ports | Four 8-bit I/O ports |
| Timers/Counters | Two 16-bit timer/event counters |
| Instruction Set Size | Over 100 instructions: 49 one-byte, 45 two-byte and 17 three-byte |
| Operating Frequency Range | 3.5MHz — 24MHz (depending on package) |
| Temperature Range | -40 to +125 °C (Industrial grade) |
The 87C654 has the same instruction set as the 80C51 microcontroller family.
There is an 83C654 version with mask programmable ROM and an 87C654 version with EPROM.