We can read MCU IC Atmel 8051 AT89C55WD, please view below chip features for your reference:
Compatible with MCS®-51 Products
20K Bytes of Reprogrammable Flash Memory
Endurance: 10,000 Write/Erase Cycles
4V to 5.5V Operating Range
Fully Static Operation: 0 Hz to 33 MHz
Three-level Program Memory Lock
32 Programmable I/O Lines
Eight Interrupt Sources
Programmable Serial Channel
Low-power Idle and Power-down Modes
Interrupt Recovery from Power-down Mode
Hardware Watchdog Timer
Dual Data Pointer
Power-off Flag
Green (Pb/Halide-free) Packaging Option