The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the industry-standard 80C51 instruction set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with in-system programmable Flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller which provides a highly-flexible and cost-effective solution to many embedded control applications.
The AT89S52 is a low‑power, high‑performance 8‑bit CMOS microcontroller with 8 KB of in‑system programmable Flash memory, 256 bytes of RAM, and 32 programmable I/O lines. It supports a 4.0 V to 5.5 V operating range and can run up to 33 MHz, offering features such as a watchdog timer, three 16‑bit timer/counters, and a full‑duplex UART.
The document includes a detailed pin‑out for 40‑lead PDIP, 44‑lead PLCC and TQFP packages, a block diagram of the internal architecture, descriptions of each port and special function registers, and tables of register reset values. Package dimensions and mechanical drawings are also provided.
| Flash Memory | 8 KB |
|---|---|
| Operating Voltage | 4.0 V to 5.5 V |
| Maximum Clock Frequency | 33 MHz |
| Internal RAM | 256 bytes |
| Programmable I/O Lines | 32 |
| Timer/Counters | Three 16‑bit |
| Interrupt Sources | Eight |
| UART | Full‑duplex serial channel |
| Watchdog Timer | Included |
| Dual Data Pointer | Included |
The AT89S52 operates from 4.0 V to 5.5 V.
It contains 8 KB of in‑system programmable Flash memory.
The device provides 32 programmable I/O lines.
It can run up to 33 MHz.