I might misunderstand you, but you just want to save a value in a PIC16F84 to use again after powerdown ?

Why not use the WRITE and READ command. ?

Below is some code snippets I use on a motor control.
When I switch power off I want to keep a value for the next time I switch power on again.

==== Start of program ====
...
...
read 1, Min_Start 'Read stored value of Minimal start speed
if Min_Start=255 then Min_Start=0 'Min_start was not stored
...
...
...
Write 1, Min_Start 'Somewhere in program the value is written.
'to Location 1

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