The Atmel AT89C55 is a microcontroller based on the popular 8051 architecture. It features 20K bytes of Flash programmable and erasable read-only memory (PEROM) and 256 bytes of RAM. It's designed for embedded control applications where larger program memory is needed compared to the AT89C51/52 family. This device is manufactured using Atmel's high-density nonvolatile memory technology.

Applications

• Industrial Control Systems
• Motor Control
• Smart Card Readers
• Security Systems
• Data Acquisition

Features

• Compatible with MCS-51 Products
• 20K Bytes of In-System Programmable (ISP) Flash Memory
• Endurance: 1,000 Write/Erase Cycles
• 4.0V to 5.5V Operating Range
• Fully Static Operation: 0 Hz to 24 MHz
• Three-level Program Memory Lock
• 256 x 8-bit Internal RAM
• 32 Programmable I/O Lines
• Three 16-bit Timer/Counters
• Six Interrupt Sources
• Programmable UART Serial Channel
• Low-Power Idle and Power-down Modes

Benefits

• Larger Program Memory: The 20K Flash memory allows for more complex and feature-rich applications.
• Easy to program: The 8051 architecture is widely known and supported, making development straightforward.
• Versatile: Suitable for a broad range of embedded control tasks thanks to its rich set of peripherals.
• Power efficient: Idle and Power-down modes minimize energy consumption.
• In-System Programmable: Enables easy firmware updates and customization without removing the chip.

Additional Details

The AT89C55 microcontroller typically operates in the 4.0V to 5.5V voltage range and supports a maximum clock frequency of 24 MHz. It contains a full-duplex UART serial channel for convenient serial communication. It is usually available in 40-pin PDIP, PLCC, or TQFP packages. The flash memory is rated for at least 1,000 write/erase cycles. The device is now end-of-life.