Rockwell Automation 9323-S5500D A.I. SERIES MICROLOGIX 1000 AND PLC-500 SOFTW - Manual (Page 531)

D
Bit & Word Mnemonics
Address and Symbol Parsing
SLC 500 addresses use delimiters between the characters to specify the data file types
and number (fn), the file element (e), and file subelement (w) or bit number (b) within
that file. When you enter addresses or symbol names during ladder programming or
program documentation, the input is “parsed” to check it for validity.
To facilitate address entry, the colon (:), semicolon (;), and space character, represented
on the screen with an underscore (_), are valid delimiters between the (fn) and (e)
portions of a data table address (spaces are always converted to underscores when
entering addresses).
For example: T4:0
T4;0
T4_0 are all parsed as T4:0 .
When you specify a subelement (w) or bit number (b), you can enter a slash (/) or
period (.) in addition to the above characters as valid delimiters.
For example:
N7:0/11 may be entered as: N7_0_11 but not as: N7/0/11
N7;0;11 or N7.0.11
N7;0.11
and N7;0/11
You can assign symbol names to word or bit addresses and use them instead of those
addresses.