Troll Your Neighbors By Multiple Fake SSIDs Using ESP8266!

After we tinkered with a really useful project to convert esp8266 to a WiFi Repeater, now it’s time for having fun!

End year is the best time to troll your annoying neighbors (or be the annoying one instead), maybe we already did this by renaming our WiFi name into some weird description like “Your Momma Is So Fat” or “Your Music Taste Is Suck!”, but this article helps you to disturb your evil neighbors even further by broadcasting multiple SSIDs at the same time. There’s no limit to your SSID list so that you can use this for advertisement. Are You Ready, Evil?

To do this project you’ll need an esp8266 module like NodeMCU and a micro USB cable.

Simple Steps To Annoy Your Neighbors

  1. Download this Arduino sketch via GitHub here. Or if you don’t know how to do it, simply click this link here.
  2. Connect your esp8266.
  3. Extract the downloaded zip and open the *.ino file with Arduino IDE, I assume you know how to program esp8266 module using Arduino IDE.
  4. If you want, alter what SSIDs to be broadcasted by modifying RickRoll() function in line 116.

    Trolling…
  5. Flash the sketch into your esp8266 module.
  6. Enjoy!

How To Build WiFi Repeater Using ESP8266! Simple!

Sometimes it is really irritating when your WiFi signal suddenly drops because you are too far from the router in your office. Other time, you get the poorest signal strength possible because one router is too limiting in your wide house. It’s tedious to move from your comfortable bed, but buying another router will cost too much.

Isn’t it very convenient when you can extend your WiFi range as cheap as possible, yet the extender is still portable? This article will help you to do that by using a small yet cheap module: ESP8266.

Poor Signal Strength

For this purpose, I use NodeMCU. I was shocked when I discovered the connection speed is blazingly fast for a constrained module like esp8266. At the end of this article, I’ll show you my speedtest result for both with and without this WiFi extender.

Tools

To build this device, you’ll only need one nodeMCU (or two, if you want to extend even further), and a microUSB cable.

Steps

  1. Download this GitHub project here. Download as zip. If you don’t know how to download it, click this link: esp_wifi_repeater-master.
  2. Download Flash Download Tool by following this post until step 4.
  3. Extract esp_wifi_repeater-master.zip to a folder.
  4. Back to your Flash Download Tool window, click the ‘…’ button, and choose folder firmware and finally select file 0x00000.bin.
  5. Repeat for the second ‘…’ button, and choose 0x10000.bin
  6. Select the first two checkboxes, and make sure all other settings are set exactly like this window below:

    Make sure all settings are correct
  7. Enter flash mode (if you don’t know how to do it, please follow this article). If you use NodeMCU, skip this step.
  8. Click Start. The firmware will be flashed. When finished, your esp8266 will broadcast a new SSID called “myAP”. Connect to this AP.
  9. Open your browser, and open 192.168.4.1. Now you should get something like this:

    Configuration Page
  10. In STA Settings section, enter your target SSID and password (i.e. the one which has an active internet connection). Click Connect.
  11. In AP Settings section, enter your esp8266 module SSID and password (the one you will be connected to). Click set.
  12. Your esp8266 module will be rebooted. Now you can connect to your esp8266 SSID.
  13. Enjoy!

Now, you should be able to do anything on the internet, just like your normal hotspot.

Speedtest Result

I tested both my internet speed with speedtest, just curious how well this extender performs:

Without Extender

Without Extender

With Extender

With Extender

Other users have reported their device can achieve 6 Mbps (~750 KB/s). At least I’m still able to stream youtube at 720p without too much buffering.

How To Enter Flash Mode In Your ESP8266 Module!

Your ESP8266 Module has two modes: normal, and flash mode.

Normal mode is where you run your program, ESP8266 module default mode should be this mode. You apply power to your ESP8266, and beep, your ESP8266 is running seamlessly. If your ESP8266 module just has blank program, then it will only do nothing.

The flash mode is where you update your ESP8266 module program, any program that already inside the module won’t run in this mode, but you are able to update the program inside the ESP8266 flash memory. Entering flash mode is easy as pie.

Basically, you just want to tie the GPIO-0 (zero) pin to the ground. If that pin is tied up to VCC or left floating, then the module will enter normal mode. This article will help you to enter flash mode for ESP-01, ESP-12E, and NodeMCU module.

ESP-01

To put your ESP-01, just follow the connection below. CH_PD stands for “Chip Power Down” and must be tied up. RXD and TXD are the UART receive and transmit pins, connect them to your USB-to-Serial module.

ESP-01 Pinout

Make sure you have connected those pins correctly before you apply 3.3v.

ESP-12E

For ESP-12E module, follow this diagram.

ESP-12E flash mode

Like ESP-01, make sure you have correctly connected those pins before applying 3.3v. The ESP-12E pin pitch is fairly small, you may want to use breakout board to conveniently connect the pins.

NodeMCU

NodeMCU flash mode

NodeMCU is the easiest to enter flash mode. After you plugged power to the USB:

  1. Press the flash button
  2. Don’t release the flash button yet
  3. Press the RST button
  4. Release the RST button
  5. Release the flash button

Now you should have entered flash mode in your NodeMCU module.

If you want to check your ESP8266 flash size, check this article: How To Check Flash Size in Your ESP8266 Module! Simple Way

How To Check Flash Size in Your ESP8266 Module! Simple Way

It is really frustrating when we buy shielded ESP8266 modules with wrong flash size (e.g. 16 Mbits instead of 32 Mbits), really annoying because simply the flash chip is covered by a metal shield.

Which is the 32 Mbits version, and the 16 Mbits version?

Here is how you find out the flash size using ESP8266 Flash Download Tool:

  1. Power up your ESP8266 module, and enter flash mode (if you don’t know how to enter flash mode, read How To Enter Flash Mode In Your ESP8266 Module!)
  2. Extract the archive and open ESPFlashDownloadTool_vx.x.x.x.exe where x is your tool version.

    Flash Download Tool Folder
  3. Click ESP8266

    Click the ESP8266 DownloadTool
  4. You will get this window:

    Download Tool Window
    Download Tool Window
  5. Make sure you’ve connected your ESP module UART pins to PC (with USB-to-Serial TTL or using Arduino). Select the correct COM port and Baudrate, then simply click the start button.
  6. In the “detected info” box, the flash size will be specified in Megabits, to convert to megabytes simply divide that number with 8 (32 Mbits = 4 MBytes).
    Flash size shown in detected info box

     

  7. Done!

Contoh Program Solver Untuk Knight Tour Problem

Berikut ini saya berikan kode sumber untuk menyelesaikan persoalan Knight Tour. Knight Tour adalah suatu permasalahan dalam catur, dengan aturan kuda harus dapat melewati semua kotak catur tepat satu kali.

 

/*
Knight Movement Solver Program
*/

#define BOARDSIZE 5

#include
#include

typedef struct {
// Position of the knight.
int x;
int y;
} point;

typedef struct {
int count;
point moves[8];
} move;

int main(void)
{
// Object declaration
int board[BOARDSIZE][BOARDSIZE];
point currentPosition = {0, 0};

// Algorithm
printf("Current Position: (%d,%d)\n", currentPosition.x, currentPosition.y);

return 0;
}

// Calculate next possible move for given position
move nextPossibleMove(point position, int *board)
{
int count = 0;
point p;
// There is maximum 8 possible movement for knight
// in any position.

move m = {0, NULL};
return m;
}