Product description of SIEMENS PLC CPU 6ES7212-1AE40-0XB0:
The 4 input/output boards can expand up to 2 expansion modules, 4 fast counters (30 kHz), 2 high-frequency pulse outputs (maximum 20 kHz). The battery module performs long-term backup. The CPU hardware supports obtaining more program storage options by switching the operating mode. The CPU 224XP supports PID control, I/O, and two communication ports. The CPU 226 includes input filters and pulse capture facilities for each port. The processing time per instruction is 0.22μs. Modular expansion adds up to 256 I/O points (except S7-221). It features a powerful instruction set and real-time performance via the RS-485 communication port for programming. All models have EEPROM storage for user programs or 4×30kHz pulse outputs (limited to DC power supply models).