The top left button counts up. The top right counts down. The bottom left button shows the number you imputed in binary. The bottom right button resets the display. The fifth binary switch puts a decimal point.
1000 = 1
0100 = 2
1100 = 3
0010 = 4
1010 = 5
0110 = 6
1110 = 7
0001 = 8
1001 = 9
0101 = A (removed)
1101 = B (removed)
0011 = C (removed)
1011 = D (removed)
0111 = E (removed)
1111 = F (removed)
