1766-RM001A-EN-P MicroLogix 1400 Programmable Controllers ...

System Status File 553Status File DetailsArithmetic FlagsThe arithmetic flags are assessed by the processor following the executionof any math, logical, or move instruction. The state of these bits remainsin effect until the next math, logical, or move instruction in the program isexecuted.Carry FlagAddress Data Format Range Type User Program AccessS:0/0 binary 0 or 1 status read/writeThis bit is set (1) if a mathematical carry or borrow is generated.Otherwise the bit remains cleared (0). When a STI, High-Speed Counter,Event Interrupt, or User Fault Routine interrupts normal execution of yourprogram, the original value of S:0/0 is restored when execution resumes.OverFlow FlagAddress Data Format Range Type User Program AccessS:0/1 binary 0 or 1 status read/writeThis bit is set (1) when the result of a mathematical operation does not fitin the destination. Otherwise the bit remains cleared (0). Whenever thisbit is set (1), the overflow trap bit S:5/0 is also set (1). When an STI,High-Speed Counter, Event Interrupt, or User Fault Routine interruptsnormal execution of your program, the original value of S:0/1 is restoredwhen execution resumes.Zero FlagAddress Data Format Range Type User Program AccessS:0/2 binary 0 or 1 status read/writeThis bit is set (1) when the result of a mathematical operation or datahandling instruction is zero. Otherwise the bit remains cleared (0). Whenan STI, High-Speed Counter, Event Interrupt, or User Fault Routineinterrupts normal execution of your program, the original value of S:0/2 isrestored when execution resumes.Publication 1766-RM001A-EN-P - October 2008