GE Fanuc | Series 90-30 | IC693PRG300 - GE Fanuc PLC

1Several functions may be performed independent of the current mode of operation.These functions include mode selection and starting or stopping the PLC. Please refer tochapter 7, PLC Control and Status.ReferencesThe data used in an application program is stored as either register or discretereferences. When entering a statement list program you must assign references to datain the PLC system. A reference specifies both a memory type and a precise locationwithin that memory type. For example: %I0001 specifies address 1 in discrete inputmemory and %R0256 specifies address 256 in register memory.The %I symbol is used by the PLC to distinguish machine references from nicknames(the % symbol is not entered or displayed on the HHP).The valid register and discrete references that are used with the Series 90-30 and Series90-20 programmable logic controllers are described in the following two tables.TypeTable 1-1. Register ReferencesDescription%R The prefix %R is used to assign system register references, which will store program data such as theresults of calculations.%AI%AQThe prefix %AI represents an analog input register. This prefix is followed by the register address of thereference (for example, %AI0015). An analog input register holds the value of one analog input or othervalue.The prefix %AQ represents an analog output register. This prefix is followed by the register address ofthe reference (for example, %AQ0056). An analog output register holds the value of one analog output orother value.NoteAll register references are retained across a power cycle to the CPU.GFK-0402GChapter 1 Introduction to the Hand-Held Programmer1-3