Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal - Manual (Page 158)

Chapter 7
Creating and Editing a Program File
7–46
2. To create elements N7:0 through N7:12, press [F1] , CRT_DAT, type
N7:12 and press [ENTER] . The following display appears:
CRT DT DEL DT NEXT PG PREV PG PRG SIZE
F1 F2 F3 F4 F5
File Type LastAddr Elements Words
7 N integer N7:12 13 13
8 Reserved – – –
0 O output O0:3.0 1 1
1 I input I1:2.0 2 2
2 S status S2:15 16 16
OFL
The memory map indicates that the integer (N) file 7 size is 13 elements
(equivalent to 13 words) and the last address is N7:12.
Deleting Data Files
When you modify your ladder program and delete instructions, any
corresponding data file addresses are not de–allocated. For efficient memory
usage, it is best to delete unused data file addresses.
You cannot delete a data file element that is used in your ladder program.
Neither can you delete an unused element within a file if a higher number in
the file is used in your ladder program. Also, you cannot delete elements in
the output file (file 0), input file (file 1), or status file (file 2). These files can
only be deleted through the processor and I/O configuration.
Data is deleted by entering the lowest numbered element you want to be
deleted. For example, entering element N7:12 (default integer file 7) deletes
element N7:12 and all existing higher numbered elements.
To delete elements N7:5 through N7:12, press [F2] , DEL_DT from the
memory map display, type N7:5 and press [ENTER] . The following display
appears:
CRT DT DEL DT NEXT PG PREV PG PRG SIZE
F1 F2 F3 F4 F5
File Type LastAddr Elements Words
7 N integer N7:4 5 5
8 Reserved – – –
0 O output O0:3.0 1 1
1 I input I1:2.0 2 2
2 S status S2:15 16 16
OFL
The memory map now indicates that the integer (N) file 7 size is 5 elements
(equivalent to 5 words) and the last address is N7:4.