Allen-Bradley MicroLogix 1200 Reference Manual page 169

Clearing S:14 before executing the FRD instruction is shown below:
I:1
] [
0
When the input condition I:0/1 is set (1), a BCD value (transferred from a
4-digit thumbwheel switch for example) is moved from word N7:2 into
the math register. Status word S:14 is then cleared to make certain that
unwanted data is not present when the FRD instruction is executed.
MOV
MOVE
Source N7:2
4660
Dest S:13
4660
CLR
CLEAR
Dest S:14
0
FRD
FROM BCD
Source S:13
00001234
Dest N7:0
1234
Conversion Instructions 11-7
0001 0010 0011 0100
S:13 and S:14 are
displayed in BCD format.
0000 0100 1101 0010
Publication 1762-RM001C-EN-P