Pseudo-addresses, Instruction addresses, Ladder files – Rockwell Automation 9323-S5500D A.I. SERIES MICROLOGIX 1000 AND PLC-500 SOFTW User Manual
Page 194: Data table files

MicroLogix 1000 and PLC-500 A.I. Series Software Reference
9-4
Pseudo-addresses
Pseudo-addresses are used for:
•
instruction types that do not have real data table addresses. The PLC-500 A.I.
software generates pseudo-addresses to provide a database record point for these
instruction types.
•
text attached to ladder program file numbers
•
text attached to data table file numbers
•
descriptions assigned to I/O cards
Instruction Addresses
Address
Description
U:
n
JSR
and
SBR
Jump subroutine, where
n
is the destination ladder file number
Q
n:n
JMP
and
LBL
Jump to label, where
n:n
is the ladder file number and label number
V:
n
RET
Return from subroutine, where
n
is the ladder file number where the
RET resides
Ladder Files
The ten character name for the program file is stored in the .NAM file (not in the
processor). A database record is created in the format PFILE:
nnn
, where
nnn
is the
ladder file number. The database record is used to store the forty character program
file description.
Note
Because the ten character name is stored in the .NAM file on disk, and not in the
SLC 500 processor, uploading from the processor will erase existing filename
descriptions.
Data Table Files
The ten character name and 40 character description are stored in a database record in
the format DFILE:
nnn
, where
nnn
is the data file number.