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Saturday, 21 March 2015

This may seem like a very simplistic question that does not need answering when, in fact, it is a question that many people do not know the true answer to. Computers have existed a lot longer than the transistor in mechanical and theoretical form. The actual definition of a computer was thought up by a very intelligent individual by the name of Alan Turing. He described a machine that was termed the Turing Machine. Every computer that we use today, from the computer or cell phone that you are reading this on to supercomputers all can be classified as a Turing Machine at their most simplistic level.

What is a Turing Machine? A Turing Machine consists of 4 parts: the tape, head, table and state register. To visualize the operation of such a machine you first have to imagine a film strip spanning infinitely in each direction. Now imagine that each cell of this film strip can contain only one of a defined set of symbols (like an alphabet). For this example let us imagine that each cell can only contain either a "0" or a"1". These cells can be rewritten an infinite amount of time but retain their information indefinitely until they are changed again. The part of the Turing Machine known as the head can write symbols to the cells as well as either increment or decrement its position on the film strip by a given integer (whole number) of cells. The next part is the table which holds a given set of instructions for the head to execute such as "move right 4 cells" and "set cell to 1". The fourth and final part of a Turing Machine is its state register whose purpose is to hold the current state of the machine. The state includes the instruction as well as the current data on the tape.

That is how simple the operation of a computer is. When your computer operates, it is actually operating as a turing machine. It processes data held on your computer by a given set of instructions and algorithms. The computer described in this Instructable is a very simplistic model of a computer, but it still operates as one that you can program with a set of instructions that it will follow and execute.

Friday, 20 March 2015

NAT
To translate address.

Firewall
To burn infectious packet.

Access-list
To disable a host to access another host.

SNMP
To send devices log to another device that standby to capture.

Dynamic routing
To tell other router when one router is changing their network that he serve.

QoS
To better serve one packet type than another packet type.

The IDEA is before you able to develop bigger network you may try to use small device.

Here at home, I have 2 wireless router that have capabilites such dynamic routing, nat, firewall, and bandwidth.

1 router is connected to the internet, other not directly connected to the internet;

Warning: TP-Link only support 1 network address per cable and wireless.

So we only have chance to build 2 network address on our network.

Task you need to do to accomplish are:
0. Setup wireless setting
1. Bridging 2 wireless SSID
2. Configure and use dynamic routing of both routing so host can communicate
3.

To configure dynamic routing, you need data:
1.
2.

2. Bridging 2 wireless SSID
To configure bridging, you need data:

3. Access restriction
To restrict an access you need:
1.
2.
3.

4. To limit the bandwidth
- Out of router 2 router 1, you need data:

5. To NAT certain address you need a data:
1. What address

6. To setting Firewall you need data:
- Are you use SPI

Javascript application are:
1. Database-driven application
2. Animated 2D and 3D graphics
3. Create games
4. Make things happen when you click a button
5. Image galeries
6.

Start 1: Hello World
1. Create a folder call it "scripts"
2. Then outside that folder create main.js and index.html
3.

Thursday, 19 March 2015

Apa saja sih yang bisa dibangun dengan javascript:

Javascript bisa apa saja?

1. Javascript bisa mengubah isi dari html

Misalnya:

document.getElementById("demo").innerHTML = "Hello JavaScript";

2. Javascript bisa mengubah atribut / properti html

Misalnya:

3. Javascript bisa memvalidasi data. Contoh sebagai berikut:

<!DOCTYPE html>

<html>

<body>

<h1>JavaScript Can Validate Input</h1>

<p>Please input a number between 1 and 10:</p>

<button type="button" onclick="myFunction()">Submit</button>

function myFunction() {

var x, text;

// Get the value of the input field with id="numb"

x = document.getElementById("numb").value;

// If x is Not a Number or less than one or greater than 10

if (isNaN(x) || x < 1 || x > 10) {

text = "Input not valid";

} else {

text = "Input OK";

}

document.getElementById("demo").innerHTML = text;

}

</script>

</body>

</html>

Transistor Lab #2 : Counter circuit

Counting in binary is sophisticated technique hardly to figures; but I finally understand but I almost go insane, that is how transistor used to do arithmatic add between 2 bits together.

At first sight you will really hardly found the key concept. I am in electronics for 5 years, but I finally understand the key in my last year.

The hardest part of binary arithmatic (specially adding together bits) are the carry concept / mechanism.

We can just do binary arithmatic using XOR operation, but when we add 1 + 1 the result shoud be 2, but binary limited the output into 0, 1. There is no number 2. This I confuse about.

But, after reading a lots of tutorial I know now that the carry mechanism it self is using another designated circuit. So there are 2 circuit in arithmatic adder.

The carry circuit was OR circuit and the add circuit is XOR operation. So the total is 2 circuits but supplied with same two A and B input. And the output must be 2. So counting in binary need 2 output, in this case 2 LEDs.

Lets build it

First build an XOR circuit and then built the OR circuit and then connect the A, and B input and then connect the 1 LED to XOR circuit and another LED to OR circuit.

HOW can computer count binary

1. We need to know how computer add 1 bit binary

A	B	Out
0	0