BCD thumbwhell

I am working with a SLC 500 plc (1747-L40A)with a two slot expansion rack. In slot one of the rack I have a 1746-IB16 input card. I have a BCD thumbwheel wired to this card. I programmed a clock using a timer for seconds advancing a counter for minutes that advances a counter for hours. I want to use the input from the thumbwheel to go into the preset of the hour counter to control turn an output on after the counter has reached the setting of the thumbwheel. I have tried to take the input I:1.0 and use it as a source for a FRD instruction and specify S:13 or N7:0 for a destination. When I enter any of these values it shows them as valid entries, but when I verify the program or try to go on line the value I placed as a source (I:1.0) is always changed to S:13. How do I get the value shown in I:1.0 from the thumbwheel into a register I can use. I am following the example on page 1-50 of Rockwells SLC 500 processors documentation reference guide. What am I doing wrong

501 Limitation

With the 5/01's the destination of a FRD must be one of the math registers, the processor has two, S:13 low word and S:14 high word, which can be used together for a 32 bit word. However in your case you don't need the 32 bit, so try the following and see if it will function as a workaround.

Clear S14 First!

Consider this:

Warning! If the math register (S:13 and S:14) is used as the source, and the BCD value does not exceed 4 digits, be sure to clear word S:14 before executing the FRD instruction. If S:14 is not cleared and a value is still in this word from another math instruction, an incorrect value will be placed in the destination word.

Rockwell Software 2000

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Good catch Lancie1,
it's been a looooonnng time since I did anything on a 5/01