- The development environment of the designed PLC SW architecture is as follows:
- ThinkPad E130 (X86 CPU cored Notebook)
- Xenomai-2.6.5 & gcc 4.8.4
- Three stepping motors and motor drivers (SMMC42S)
Table 1. SMMC42S Stepping Motor Driver
- Our system SW consists of a master program and a slave program. They exchange variables and events through the shared memory with other. The Master includes an interpreter which reads and executes the prepared programs sequentially. The Slave uses the shared memory for updating each variable and event, and connecting the system and the motors and a keyboard with each legacy program.
Fig. 3. Structure of implmented PLC
- When user hits the keyboard, operation data are transferred the master which has the CTUD (UpDownCounter), SUM, and MUL functions to determine the moving axis and position requirment of the motor. It stores this information in the shared memory using the Move function, and then drive the motor through the slave