How do you read out the IP address of the S7-300 CPU in the user program at run time? You call the "RDSYSST" instruction in order to read out the IP address of the S7-300 CPU in the user program. With the "RDSYSST" instruction you can read out a parts list or excerpt of a parts list of the system status lists (SSL or in German SZL). With the SSL ID and the INDEX you specify the parts list or excerpt of the parts list and the type or number of an object in a parts list. Use the SSL ID = 37 (hex) and the INDEX = 0 (hex) to read out the IP address of the S7-300 CPU. Fig. 01 Inputs and outputs of the "RDSYSST" instructions Table 01 shows the inputs of the "RDSYSST" instruction. Parameter Data type Description REQ BOOL REQ=1: Trigger for processing SSL_ID WORD SSL_ID of the parts list or of the excerpt of the parts list SSL_ID=w#16#37: Read out of the IP address of the S7-300 CPU INDEX WORD Type or number of...