;***********************************************************************
;
      FUNCTION IGAIN,ISARS
;
      CHECKVAR,IDGAIN,6 
    
      IMASK1='3800'X
    IMASK2='700'X
    IMASK3='E0'X
    IMASK4='1C'X

      IGTABLE =[8,4,6,2,7,3,5,1]
;
      IGAIN1= ISARS AND IMASK1
      IGAIN2= ISARS AND IMASK2
;
      IGAIN1=IGAIN1/('800'X)
      IGAIN2=IGAIN2/('100'X)

        IF IGAIN1 EQ IGAIN2 THEN BEGIN
          GAIN_STATE=IGTABLE(IGAIN1 )
          RETURN,GAIN_STATE
        ENDIF

      IGAIN3 = ISARS AND IMASK3
      IGAIN4 = ISARS AND IMASK4

      IGAIN3 = IGAIN3/('20'X)
      IGAIN4 = IGAIN4/('4'X)

        IF IGAIN3 EQ IGAIN4 THEN $
          GAIN_STATE=IGTABLE(IGAIN3) ELSE GAIN_STATE=IDGAIN

    RETURN,GAIN_STATE
      END