This review is written from the perspective of an automation engineer or Siemens PLC technician. 1. Product Context The Siemens SIMATIC PC Adapter USB A2 (6GK1571-0BA00-2AA0) is a programming interface (PG/PC interface) that connects a standard USB port on a computer to the MPI (Multi-Point Interface), PROFIBUS, or PPIs of a Siemens PLC (S7-200/300/400). Unlike its predecessor (RS232-based), the A2 is native USB.