This Recommendation has been amended to include the preferred option for showing the relationship between letters and digits, where both appear on a keypad or dial. Additionally, in order to assist blind or visually impaired people in identifying the dialling push-buttons, it has been recommended that the button with the digit 5 be marked with a tactile identifier.
Số hiệu tiêu chuẩn
ITU-T E.161
Tên tiêu chuẩn
Arrangement of digits, letters and symbols on telephones and other devices that can be used for gaining access to a telephone network
Ngày phát hành
2001-02-00
Từ khóa
Communications * Integrated services digital network * ISDN * Letters (symbols) * Manipulating devices * Symbols * Telecommunication * Telecommunications * Telephone equipment * Telephone networks * Telephones