LIST_FROM_MEMORY

Hello Gurus,

Someone please can help me to convert the table that is return by the function LIST_FROM_MEMORY into ascii with a field type C larger than 250 characteres?

call function 'LIST_FROM_MEMORY'
       tables
            listobject = it_listobj
       exceptions
            not_found  = 1
            others     = 2.

I am using this 

    CALL FUNCTION 'LIST_TO_ASCI'
      TABLES
        listasci                 = it_ascii
        listobject               = it_listobj   
      EXCEPTIONS
        empty_list               = 1
        list_index_invalid       = 2
        OTHERS                   = 3.

But I got an error because the field of internal table it_ascii has a field TYPE string, I have this because the function LIST_FROM_MEMORY returns it_listobj very large, so that's because I have to declare a type STRING field.

TYPES: BEGIN OF ty_ascii,
      line TYPE string,
END OF ty_ascii.

Thanks in advance for your help gurus