Allen-Bradley Logix5000 Reference Manual page 608

Chapter 18 ASCII String Instructions (CONCAT, DELETE, FIND, INSERT, MID)
If you want to
Compare a string to another string
See if the characters are equal to specific characters
See if the characters are not equal to specific characters
See if the characters are equal to or greater than specific characters
See if the characters are greater than specific characters
See if the characters are equal to or less than specific characters
See if the characters are less than specific characters
Rearrange the bytes of a INT, DINT, or REAL tag
Find a string in an array of strings
Convert characters to a SINT, INT, DINT, or REAL value
Convert characters to a REAL value
Convert a SINT, INT, DINT, or REAL value to a string of ASCII characters
Convert REAL value to a string of ASCII characters
608
You can also use the following instructions to compare or convert
ASCII characters.
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Use this instruction Page
CMP 221
EQU 226
NEQ 257
GEQ 226
GRT 234
LEQ 238
LES 242
SWPB 311
FSC 361
STOD 623
STOR 625
DTOS 627
RTOS 629