problem in converting SI to char with 'FLTP_CHAR_CONVERSION_FROM_SI'

hi friends i am using following code in one of my program but the output is comming as

****

I have checked in the debugging mode.

REPORT  ZTEST5.
data : hexvalue like IMRG-RECDV,
      charval(4) type c.


hexvalue = '2.6000000000000000E+04' .
          CALL FUNCTION 'FLTP_CHAR_CONVERSION_FROM_SI'
          EXPORTING
          char_unit = 'EA'
          unit_is_optional = 'X'
          decimals = 0
          exponent = 0
          fltp_value_si = hexvalue
          indicator_value = 'X'
          masc_symbol = '_'
          IMPORTING
          char_value = charval
          EXCEPTIONS
          no_unit_given = 1
          unit_not_found = 2
          OTHERS = 3.

         write : 'charvalue',charval.

i have to use char value further.Please guide me where is the problem