>  A question please this is for a pic 16c84:
>         BSF     STATUS,RPO      ;select bank 1
>         MOVLW   31              ;value used to initialize data direction
>         MOVWF   TRISA           ;set ra <0:4> to input mode
>         CLRF    PORTB,1         ;Initialize portb by clearing output data
 latches

Note: Bit RP0 of STATUS is still set when you get here; ergo, your CLRF will
      be writing to TRISB.

>         BSF     STATUS,RPO      ;select bank 1
>         MOVLW   55              ;value used to initialize data direction
>         MOVWF   TRISB           ;set rb <0:7> to output mode
>         BCF     STATUS,RPO      ;select bank 0
>         CLRF    PORTB,1         ;return output pins low

This time you actually do clear RP0, so the second CLRF attempt should
succeed.