Monday, March 14, 2016

Bonus 2 : Tip and trick with Raspberry Pi


GETTING THE NETWORK DETAILS

To scan for WiFi networks, use the command
sudo iwlist wlan0 scan | grep 'ESSID\|IE: IEEE'
This will list all available WiFi network names and their encryption methods. Look for yours in the list:
  1. ESSID:"yournetwork". This is the name of the WiFi network, find the one that you want to use.
  2. IE: IEEE 802.11i/WPA2 Version 1.
    1. This is the authentication used; in this case it is WPA2, the newer and more secure wireless standard which replaces WPA1. This guide should work for WPA or WPA2, but may not work for WPA2 enterprise; for WEP hex keys.

ADDING THE NETWORK TO THE RASPBERRY PI

Open the wpa-supplicant configuration file in nano:
sudo nano /etc/wpa_supplicant/wpa_supplicant.conf
Go to the bottom of the file and add the following:
network={
    ssid="The_ESSID_from_earlier"
    psk="Your_wifi_password"
}
In the case of the example network, we would enter:
network={
    ssid="testing"
    psk="testingPassword"
}
Now save the file by pressing ctrl+x then y, then finally press enter.
At this point, wpa-supplicant will normally notice a change has occurred within a few seconds, and it will try and connect to the network. If it does not, either manually restart the interface with
sudo ifdown wlan0
and
sudo ifup wlan0
or reboot your Raspberry Pi with
sudo reboot
You can verify if it has successfully connected using ifconfig wlan0. If the inet addr field has an address beside it, the Pi has connected to the network. If not, check your password and ESSID are correct.
You can also check your DHCP server to see if it gave out a new IP address.

Remove any unneeded packages

There will eventually be packages that are unneeded. Apt-get can get rid of them by issuing this command:

sudo apt-get autoremove

Remote Desktop

Installing this allows you to connect via RDP on Windows.
sudo apt-get install xrdp

Add Chrome/Chromium to Desktop

Adds “Chrome” web browser to the GUI interface.
sudo apt-get install chromium-browser

Check CPU Clock Speed

This will show the current CPU clock speed in hertz
 cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

Raspi-config

This is the initial configuration utility. I always forget its name..
sudo raspi-config

Hướng dẫn toàn tập cho người mới bắt đầu học điện tử - phần 1


Nguồn : http://techmaster.vn/

Học điện tử cơ bản đến nâng cao tốt nhất
Mọi khởi đầu trong bất cứ lĩnh vực nào cũng có rất nhiều khó khăn, nhưng nếu bạn có động lực và quyết tâm mạnh mẽ thì chắc chắn bạn sẽ thành công. Hầu hết các sinh viên kỹ thuật điện tử đều muốn tự tay làm ra một sản phẩm gì đó. Trải nghiệm thực tế khi làm một sản phẩm nào đó là một cách học tuyệt vời. Mặc dù nó là rất quan trọng nhưng hầu hết các sinh viên không được hướng dẫn đúng đắn và họ không biết nên bắt đầu từ đâu. Tôi tin rằng loạt bài hướng dẫn này sẽ giúp cho những ai yêu thích điện tử có thể dễ dàng bắt tay vào làm các dự án của họ.

Wednesday, March 9, 2016

CÀI ĐẶT RASPBERRY PI - Bài 9 : SETUP DROPBOX FOR MOTION ON THE RASPBERRY PI


Raspbian, the recommended default operating system of the Raspberry Pi, does not come with a native Dropbox package. The hacks I saw online were all pretty sloppy, with many showing how to bounce files from your raspberry pi to another device like a desktop PC that has dropbox installed, then using that PC to sync files. I wanted Dropbox synchronization for only a single folder, and for one purpose: to collect the photos my webcam takes when using the motion software.

I decided to use Dropbox’s Python API to create a script that could save my security footage. I had a number of uninvited painters scheduled to come to my apartment while I was away at work and needed something that would save to a remote location. The code that follows is tailored to the motion program. Since motion can automatically execute a program or script upon writing a file (ie: saving a photo or video triggered by motion), I decided to take advantage of this and upload each file individually as opposed to running an additional script that continually monitors the filesystem for changes.

Tuesday, March 8, 2016

CÀI ĐẶT RASPBERRY PI - Bài 8 : SETUP Raspberry Pi as low-cost HD surveillance camera

Build a low-cost HD video surveillance cam with worldwide access from any browser

Introduction

This article describes how to build a surveillance cam based on a Raspberry Pi micro-computer which records HD video when something moves in the monitored area. Live picture can be viewed from any web browser, even from your mobile while you're on the road.
What you will get:
  • See live stream in any web browser from anywhere
  • Record any motion into video file
Hardware components
      We need some hardware for this project. This is a list of the major things we need:
  • Raspberry Pi 2 Model B: (Link : http://hshop.vn/products/moy-tonh-raspberry-pi-2-model-b-1gb-made-in-prc)
  • Raspberry Pi Camera Module (Link : http://hshop.vn/products/camera-hong-ngoai-raspberry-pi-noir)

Tuesday, March 1, 2016

CÀI ĐẶT RASPBERRY PI - Bài 7 : Điều khiển Raspberry Pi sử dụng SSH (Windows, Linux)

Mục đích:
  • Cấu hình Raspberry Pi để sử dụng tính năng điều khiển từ xa qua SSH
  • Cấu hính trên Windows, Linux để điều khiển SSH

Chuẩn bị:

  • Raspberry Pi có hệ điều hành (Raspbian Wheezy hoặc Jessie)
  • Máy tính chạy: Windows, Linux hoặc Mac

Tiến hành:

Bước 1. Cấu hình Raspberry Pi

Để có thể điều khiển Raspberry Pi sử dụng SSH thì Raspberry Pi phải được Enable SSH server.
Thông thường thì SSH Server được mở mặc định.