A key input device is provided for inputting digits/letters/characters/symbols by a keypad and a character input method for the key input device. In the key input device, a mode key is pressed to select one of a plurality of key matrixes for a corresponding mode, which is displayed on a display. A first directional key is used for inter-cell movement in the displayed key matrix and a second directional key is used to select an intended digit/letter/character/symbol within a cell. In the character input method, a mode with a unique key matrix is set by pressing a mode key. An intended cell is moved to within the key matrix by pressing a first directional key. An intended digit/letter/character/symbol is selected in the cell by pressing a second directional key. The selected digit/letter/character/symbol is displayed on a display.
展开▼