# 'Nand Game' review to assemble a circuit from scratch using a NAND gate

' NandGame ' is a website where you can learn about electronics while playing by creating various circuits that are asked in a quiz format using

NAND gates , which are known to be able to design any logic circuit by devising combinations. ..

NandGame --Build a computer from scratch.
http://nandgame.com/#

The screen of NandGame looks like this. We will install a NAND gate on the purple board and build a new circuit.

The explanation of the circuit to be assembled is written on the left. The language can be selected from English, Russian, and Chinese, and Japanese is not supported.

Drag and drop the circuit placed on the left side of the board to place the circuit.

If you drag and drop the '○' in the circuit ...

You can connect circuits to each other.

To erase the circuit from the board, drag and drop the circuit to the lower left trash can.

The first circuit to be created is 'Invert', that is, a circuit that outputs '0' for the input of '1' and '1' for the input of '0'. The NAND gate is a circuit that outputs '0' when both inputs are '1', and '0' otherwise, so if you arrange the NAND gate as follows, the Invert circuit is completed.

If you check the input part, you can check the operation by switching between '0' and '1' of the input.

When the circuit is complete, click 'I have compeleted the level' at the top left of the board.

If you have designed the correct circuit, you will see a button that says 'Level successfully completed!' And 'Next level' to go to the next level.

At the next level, the Invert circuit created earlier can be used. In this way, create a new circuit with the NAND gate, and then use that circuit to create a new circuit again ... That's how to play NAND Game.

The AND circuit is created at the next level. Since the AND circuit only needs to invert the output of the NAND circuit ...

If you connect the Invert circuit created earlier to the NAND gate, the AND circuit is completed.

You can check the cleared levels on the 'Levels' tab.

Cleared circuits are shown in green, working circuits are shown in blue, and uncleared circuits are shown in gray. You can assemble quite a lot of circuits, from basic circuits to advanced circuits such as RAM and Computer.

The

OR gate, which is the next level of the AND circuit, looks like this. Since the OR gate only needs to output '0' when both of the two inputs are '0', it is OK if the value inverted by the NAND gate is output to the AND gate and then inverted.

It can be arranged more simply by using the Invert circuit.

Click the Level Help button for a detailed description of the circuit.

However, there are no hints such as 'what circuit to arrange and how', so you may not have much chance to use it.

The layout of the XOR circuit, which is the final level of the basic circuit, is as follows.

After clearing the XOR circuit, the next step is to create an 'arithmetics' circuit.

The first arithmetic circuit can perform binary addition of one digit 'Half Adder (

The idea is simple, just input the output from the AND circuit to 'h' and the output from the XOR circuit to 'i'.

The next half-adder can be calculated a sum taking into account the carry from the digit under 'Full Adder (

full adder is)'. A full adder can be realized by using the two half adders and the OR gate.

NandGame is a game that designs the circuit correctly like this, but since there are few hints and guidance, knowledge of electronics is essential for all clearing. However, it is a good website for arranging circuits and learning the structure while looking at the schematic because it is an excellent simulator.