ERRORS

     There are a number of circumstances that will generate fatal errors.
     For example, developing a screen with only 20 fields and then trying
     to set the field Rules for field 21.

     When a fatal error occurs, a brief error message is displayed and the
     program halts.

     The following errors can occur:

     Error 1 - the Create_Fields procedure has been called with too many
     fields. The maximum number of fields the system can accommodate is
     defined in the global constant MaxInputFields. Either increase the
     constant and recompile the IOTTT5 unit or reduce the number of fields.

     Error 2 - insufficient memory to create the fields or tables. This may
     be caused by a large program running the program in the integrated
     environment - try compiling to disk and executing the program from
     DOS. The other common cause is that the heap size has been set too
     small with the {$M} compiler directive - incrementally increase the
     heap allocation until the program functions as expected.

     Error 3 - a field manipulation procedure has been called before the
     fields have been created with Create_Fields.

     Error 4 - a field ID has been used that is greater than the total
     number of fields set with Create_Fields.

     Error 5 - an attempt has been made to move to a field ID that is
     greater than the total number of fields set with Create_Fields.

     Error 6 - the Add_Field procedure has been called with invalid X, Y
     coordinates.

     Error 7 - an attempt has been made to call Add_Message for a field
     that has not yet been defined with Add_Field.

     Error 8 - an attempt has been made to call Add_Message for a field ID
     that is greater than the total number of fields set with
     Create_Fields.

     Error 9 - Add_Message has been called with invalid X, Y coordinates.

     Error 10 - Dispose_Fields has been called when there are no fields to
     dispose of, i.e. Add_Fields has not been called or Dispose_Fields has
     already been called.

     Error 11 - Create_Fields has been called twice for the same table.

     Error 12 - Activate_table has been called before Create_Tables.

     Error 13 - Activate_Table has been called with a table number greater
     than the total tables declared with Create_Tables.