The entry you make in position 35 is the data type/keyboard shift attribute for display files.
This entry does not determine the data type of the field used in your program. The entry in positions 36 and 37 (decimal positions) determines the data type of the field.
The keyboard shift attribute automatically shifts 5250 workstations with data-entry keyboards and can, for all keyboards, limit what the workstation user can type into a field. However, the keyboard shift attribute does not shift 5250 workstations with the typewriter-like keyboard. Nor does the keyboard shift attribute restrict in any way what your program can write to a field. Your program can write alphabetic characters to a numeric field and, in most cases, read that field and receive those characters. Any restrictions are enforced solely by the programming language used for your program.