CJ2 CPU Unit Software User's Manual - CIP ETI

5 Understanding Programming5-9 Checking ProgramsCJ-series programs can be checked at the following four stages.• Input check during CX-Programmer input operations• Program check by CX-Programmer• Instruction check during execution• Fatal error check (program errors) during execution5-9-1 Errors during CX-Programmer InputThe program will be automatically checked by the CX-Programmer at the following times.TimingWhen inputting ladder diagramsWhen loading filesWhen downloading filesDuring online editingCheckedInstruction inputs, operand inputs, programming patternsAll operands for all instructions and all programming patternsModels supported by the CJ Series and all operands for all instructionsCapacity, etc.The results of checking are output to the text tab of the Output Window. Also, the left bus bar of illegalprogram sections will be displayed in red in ladder view.5-9-2 Program Checks with the CX-ProgrammerThe user program can be checked in the CX-Programmer. When the program is checked, the user canspecify program check in any of four levels: A, B, or C (in order of the seriousness of the errors) or acustom check level.The CX-Programmer does not check range errors for indirectly addressed operands in instructions. Ifan instruction's operand data is invalid, the ER Flag will be turned ON during the program executioncheck, which is described in the next section. For details, refer to the CS/CJ/NSJ-series InstructionsReference Manual (Cat. No. W474).For details on the CX-Programmer's checks, refer to the CX-Programmer Operation Manual (Cat. No.W446).5-96 CJ2 CPU Unit Software User’s Manual