Rockwell Automation 1772-LS_LSP,D17726.8.6 PROG/OPER MANUAL-MINI PLC-2/05 - Manual (Page 194)

Program Editing
Chapter 16
16-17
ATTENTION: When the address of a new instruction
duplicates the address of other instructions in the program, the
[DATA INIT] key should not be used without first assessing the
consequences. Pressing the [DATA INIT] key zeros out the
status bits stored at the existing instruction address. This may
cause unwanted machine motion and result in equipment
damage and/or injury to personnel.
To look for a specific instruction, press [SEARCH] <instruction>. To look
for a specific address, press [SEARCH] <address>. This helps you to
determine addresses currently used in your program.
To locate all addresses (excluding those associated with Examine On and
Examine Off instructions and those contained within files) press
[SEARCH][8] <address>. The address entered is the word address for the
Output Energize, Latch and Unlatch instructions, the 1770-T3 terminal
locates all of the bit addresses associated with the word address.
The message “SEARCH FOR” and the entered key sequences are
displayed at the bottom of the screen. The message “EXECUTING
SEARCH” appears temporarily. The industrial terminal begins to search
for the address and/or instruction from the cursor’s position. It looks past
the temporary end and subroutine area boundaries to the END statement.
Then, it continues searching from the beginning of the program to the point
where the search began.
If found, the rung containing the first occurrence of the address and/or
instruction is displayed as well as the rungs after it. If you press
[SEARCH] again, the next occurrence of the address and/or instruction is
displayed. When another occurrence cannot be located or all addresses
and/or instructions have been found, a “NOT FOUND” message appears.
If the instruction is found in the subroutine area or part the temporary end
instruction, the area in which it is found is displayed in the lower right
hand corner of the screen.
Press [CANCEL COMMAND] at any time to terminate this function. All
other keys are ignored during the search.
In summary, use [DATA INIT] to:
enter a data instruction with an unused address
enter new data
clear the status bits of an already used address
We described how to edit instructions in your program. The next chapter
shows how to generate messages.
Chapter Summary