This is a game/activity to explain logic ports in an easy way. In this game students will signal the next student by squeezing the finger of a next student and they will relay the signal forwards, if the rule allows them to.
| Creator | Mikko Muilu |
| Subject | Math, ICT, physical education |
| Length | 45 minutes |
| Pedagogical Approach | Phenomenon-based learning |
| Competences | Boolean operators (And, or, not, xor, nand) Understanding the meaning Create human circuits |
| Grades | Students aged 9-12. |
| Technologies | Pen and paper |
AND-operator:
AND gate will only pass on the signal if both of the incoming signals are squeezed. An AND-student is chosen. His/hers left hand is the input and right hand is output. Two students take AND-students index and pinky fingers in to their hands, one finger each. AND-student takes somebody elses hand with the right output hand. If both fingers in the input hand are squeezed, AND-student should squeeze the hand/finger on the output hand.
OR-operator:
OR gate will pass on the signal if one OR both of the incoming signals are squeezed. An OR-student is chosen. His/hers left hand is the input and right hand is output. Two students take OR-students index and pinky fingers in to their hands, one finger each. OR-student takes somebody elses hand with the right output hand. If one or both fingers in the input hand are squeezed, OR-student should squeeze the hand/finger on the output hand.
NOT-operator:
NOT gate will pass on the signal if there is no incoming signal. A NOT-student is chosen. His/hers left hand is the input and right hand is output. One student takes NOT-students index finger in to their hand. NOT-student takes somebody elses hand with the right output hand. If fingers in the input hand are NOT squeezed, NOT-student should squeeze the hand/finger on the output hand.
Exercise 1:
Form groups of 4 and choose input-student(s), output-student and operator-student. These can be changed. Ask students to come up with all the different ways they can make the output student to receive a signal.
Discussion:
It wasn’t that hard, right? What could be built with operators like that?
Exercise 2:
Try to build these with the students. Now the output can go to another operator as the gates are linked together. There are three inputs in the first one (ABC) and four on the second (ABCD). Can you figure out in advance when the output will receive the signal?
Discussion:
In the first one signal goes through only when outputs A and C or B and C or all inputs are active.
In the second one the signal goes through if C is active or a and b are active or if a, b and c are active.
These are the building blocks of all computers. In its most basic form, a computer is a collection of powered and unpowered circuits and transistors. A logic gate is a series of transistors connected together to give one or more outputs, each output being based on the input or combination of inputs supplied to it. There are 1,4 billion of these in a modern computer. That is 1 400 000 000 gates.
How often do they change? That’s called the clock speed. every time computer makes one calculation, the logic inputs and outputs change. This happens many billion times in a second in a modern computer. But basically, it’s just logic gates.