M251 System Variables
Overview
This chapter:
ogives an introduction to the system variables
odescribes the system variables included with the M251 PLCSystem library
What Is in This Chapter?
This chapter contains the following sections:
oSystem Variables: Definition and Use
oPLC_R and PLC_W Structures
oSERIAL_R and SERIAL_W Structures
oETH_R and ETH_W Structures
oTM3_MODULE_R Structure
oTM3_BUS_W Structure
oPROFIBUS_R Structure