The CPU 312 is equipped with the following:

• Microprocessor;
  the processor achieves a processing time of 100 ns per binary instruction.
• Extensive memory;
  32 KB high-speed RAM (equals approx. 10 K instructions) for program components relevant to execution offers sufficient space for user programs;
  SIMATIC Micro Memory Cards (max. 8 MB) as load memory for the program also allow the project to be stored in the CPU (complete with symbols and comments).
• Flexible expansion capability
  max. 8 modules (1-tier configuration)
• MPI multi-point interface
  The integrated MPI interface can establish as many as 6 connections simultaneously to S7-300/400 or to programming device, PC, OP. One of these connections is always reserved for the PG and another one for the OP. The MPI makes it possible to set up a simple network with a maximum of 16 CPUs via "global data communication".