1. PIW282 means 2103H (output frequency).
2. PQW276 means 2000H (control word).
3. The writing of the program explains as follows.
OB1 Program (Main Loop) is explained as follows:
a. Judging if PIW282 (2103H) equals to 6000. If YES, PQW276 (2000H) equals to 1, which
means the drive stops running; if NO, go to RES label;
b. Judging if PIW282 (2103H) equals to 0. If YES, PQW276 (2000H) equals to 2, which
means the drive starts running; if NO, go to END label;
Therefore, the drive performs continuous actions of running until stop, and then starts
running again.