?at89c52單片機是美國ATMEL公司生產的低電壓，高性能CMOS 8位單片機，片內含8K bytes的可反復擦寫的Flash只讀程序存儲器和256bytes的隨機數據存儲器（RAM），器件采用ATMEL公司的高密度，非易失性存儲技術生產，與標準MCS-51指令系統及8052產品引腳兼容。功能強大的at89c52單片機適合于許多較為復雜控制應用場合。

The AT89C52 is a low-power, high-performance CMOS 8-bit microcomputer with 8K
bytes of Flash programmable and erasable read only memory (PEROM). The device
is manufactured using Atmel’s high-density nonvolatile memory technology and is
compatible with the industry-standard 80C51 and 80C52 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 Flash on a monolithic chip, the Atmel AT89C52 is a powerful microcomputer
which provides a highly-flexible and cost-effective solution to many embedded control
applications.