To type the binary digit '0', press this button.

To type the binary digit '1', press this button.

To type the four binary digits '0100' representing the hexadecimal digit '4', press this button.

To type the four binary digits '0111' representing the hexadecimal digit '7', press this button.

To type the four binary digits '1010' representing the hexadecimal digit 'A', press this button.

To type the four binary digits '1101' representing the hexadecimal digit 'D', press this button.

To change the calculator's mode to decimal and convert the displayed number, press this button.