In this tutorial we will build an 8-bit adder in four stages: half-adder, full-adder, 4-bit adder and 8-bit adder.
I. Building a half-adder
), 2 bulbs (
), 2 three-terminal
connector (
), (see Connectors), an AND-gate
(
) and an XOR-gate (
) to the circuit board; label the
endpoints and connect the components as shown:
) and save as
halfadd.cct. II. Building the full-adder
). Drag 2 halfadd cards from the subcircuit window.
), 1 bulb bank (
),
and an OR-gate (
); label the endpoints and connect as shown.
III. Building the 4-bit adder
) and choose fulladd.cct. Click
on the circuit board to add the fulladd card.
), 1 single switch, 1 bulb
bank (
), and 1 single bulb (in that order); label the
endpoints and connect as shown. Select Use Bank Pin from the
Action menus of the three terminal banks. (See Subcircuits:Special Topics: Bank Pins and LEDs).
IV. Building the 8-bit adder
) and choose add4.chp. Click
on the circuit board to add the add4 chip.
), 1 single switch, 1 bulb
bank (
), and 1 single bulb (in that order); select bank
pins, label the endpoints and connect as shown.
V. Importing add8