/FREE calculations help

I have a parameter field being passed into an RPGLE program:
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D Parm1                S             10A   DIM(100)
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If any element of the array is populated, I would like to fill as much of
each subfile field(55 characters long) on the screen as possible.  How
would you
handle this processing.  We're running V5R1.  I'm trying to use /FREE
format to code this.

I got about this far and ran out of ideas:
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            // Populate Text Fields
            P = 0;
            DOU P = 100;
            P = P + 1;
                       IF Parm1(P) <> *BLANKS;
                       #TEXT = Parm1(P) + ', ';
                         ENDIF;
             ENDDO;

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