MOV A, INSWT_FILTER
      ANL A, #1Fh          ;mask 5 low bits = 5 msec
      CJNE A, #1Fh, LABEL1 ;test if all low bits = '1'
      .... here take action to deal with 
           INSWT being filtered at '1'.
      ....
LABEL1:
      .... continue program on its way