Issues trying to understand a HTBasic code

  IF Y$="" THEN
      REPEAT
          INPUT "FILE NAME**strong text** ?",Y$
          Y$=TRIM$(Y$)
      UNTIL LEN(Y$)<8
  END IF

  DISP "enr "&Ld$&"\";Y$
  Nb_rc=VAL(Mesu$(0,5))+1
  ON ERROR CALL Ges_err
  CREATE BDAT Y$&"t",VAL(Mesu$(0,5))+2,7*34
      1   ASSIGN @Voie_0 TO Y$&"t"
      2   OUTPUT @Voie_0;Mesu$(*)
      3   ASSIGN @Voie_0 TO *
  CREATE BDAT Y$&"v",VAL(Mesu$(0,6)),(VAL(Mesu$(0,5))+1)*8
  ASSIGN @Voie_0 TO Y$&"v"
  OUTPUT @Voie_0;V(*)
  ASSIGN @Voie_0 TO *
  OFF ERROR
  RETURN

Here is some HTBasic code, I'm not able to understand what those lines (1,2,3) do.

this could be explained as:

ASSIGN @Handle TO "Filename" --> This line opens the file

OUTPUT @Handle;"TEXT" --> This linewrites to the file

ASSIGN @Handle TO * --> This linecloses the file

ASSIGN @Handle TO "Filename";FORMAT ON --> This line opens the file as text rather than binary