Welcome to the Real World

What to do ?

• Input from the mangonel sensors

• Input expected by the software

How to do ?

• Input arrives from sensors• Logic circuit combines and inverts inputs

to create a single pulse• PICAXE measures the pulse duration and

outputs the value to seven segment displays

NAND gateInput A

Input B Output

Basic Logic functions (gates):

AND OR

NOT

JK Flip-flop

Pulse width meter circuit diagram

Model on a breadboard(find TTL or “Transistor–transistor logic” in wikipedia )

Work for today

No connection

DOT means wire connection

Identifying a microchip

19

10 18

Tips and tricks:• Be tidy: Keep the wires short. This improves

reliability.• Wire Colours does not affect the performance a

circuit, but does affect the performance of a person trying to understand it.

• Connected wires are marked with a dot.• Remember about the power supply.

– Do not forget to connect– Do not forget to switch OFF when making changes.