The AT89S8253 is a low-power, high-performance CMOS 8-bit microcontroller with 12K bytes of In-System Programmable (ISP) Flash program memory and 2K bytes of EEPROM data memory.
The AT89S8253 is a low‑power, high‑performance 8‑bit CMOS microcontroller with 12 KB ISP Flash, 2 KB EEPROM, 256 B RAM and 32 programmable I/O lines. It operates from 2.7 V to 5.5 V and can run at frequencies up to 24 MHz. The device includes three 16‑bit timers, a full‑duplex UART, and a four‑level interrupt controller.
The handbook covers the device description, pin configurations for PDIP, TQFP and PLCC packages, detailed port and pin functions, the on‑chip Special Function Register map, and the auxiliary, clock, SPI and interrupt registers. Package dimensions and Atmel contact information are also provided.
| Flash program memory | 12 KB ISP Flash |
|---|---|
| EEPROM data memory | 2 KB EEPROM |
| Internal RAM | 256 × 8‑bit |
| Programmable I/O lines | 32 |
| Timer/Counters | Three 16‑bit |
| Operating voltage range | 2.7 V to 5.5 V |
| Maximum CPU frequency | 24 MHz |
| Package option | 42‑pin PDIP |
The AT89S8253 provides 12 KB of In‑System Programmable flash memory.
It has 32 programmable I/O lines.
The device operates from 2.7 V up to 5.5 V.
The CPU can run up to 24 MHz.