Rockwell Automation 1772-LS_LSP,D17726.8.6 PROG/OPER MANUAL-MINI PLC-2/05 - Manual (Page 223)

Program Troubleshooting
Chapter 19
19-2
Table 19.A
Possible Causes of Run Time Errors
Instruction Cause
Jump Jumping from the main program into the subroutine area or vice versa.
Jumping backwards.
Omitting the label instruction corresponding to the jump instruction.
Jumping over a temporary end instruction.
Label Multiple placement of the same label identification number.
Removing a label instruction but leaving its reference, the jump or
jump to subroutine instructions.
Jump to subroutine To begin your main program.
To jump forward in your main program.
Use in the subroutine area.
Omitting a return instruction.
Omitting a corresponding label instruction.
Jumping over a temporary end instruction.
Return Processor does not find a return instruction from the subroutine area.
Using a return instruction outside the subroutine area.
Files AC>PR
Duplicating counter's address.
Manipulating the counter's accumulated value by means of external
programming equipment or data highway hardware.
Sequencer File address is out of range.
Preset value equals 0.
Block transfer Giving the module address a nonĆexistent I/O rack number.
Incorrect block length value.
5. Restart your processor.
Bit Monitor Function
Bit monitor allows the status of all 16 bits of any data table word to be
displayed. It can function when the processor is operating in any mode.
By pressing [SEARCH]53<word address>, the status of all 16 bits of the
desired word is displayed. While the cursor is in the word address field,
you can use the [1] and [0] keys to change address digits.
The status of the 16 bits in the next highest or next lowest word address
can be displayed by pressing the [
↑
] or [
↓
] keys, respectively. Also, you
can use bit monitor to display the status of force conditions.
Bit Manipulation Function
Bit manipulation allows image table bits to be selectively changed. It is
useful in setting initial conditions in the data of word instructions. Bit
manipulation can function when the processor is operating in the program
Bit Monitor/Manipulation