'EP' is probably "Edge Positive" - looking to see if memory bit m200.1 has transitioned on since the last scan cycle.
'm' doesn't make sense. In Siemens STL (English) I would expect to see either an L (Load) or T (Transfer) in front of the address FD100 (Flag Double-Word 100) and FW104 (Flag Word 104). Perhaps this is a non-english way of saying it?