Sunday, 02 September 2012 14:52

Connecting ULN2803 Line Driver to Arduino

If you are using Arduino (or any other TTL device) to control 4 channel relays or more, I would suggest to use ULN2803 Line Driver instead of Transistors or FETs. You can use ULN2003 which is much more cheaper if you plan to use not more than 7 channel relays.

The ULN2803 Integrated Circuit (IC) is a "Eight-way Line Driver". It allows you to interface TTL signals (5v) with higher voltage/current (50V/500ma) loads.

As shown in figure 1 and figure 2, an Arduino is control 8 relays, one using ULN2803 line driver and the other one using transistors, both circuit are equivalent.

This is an article to guide you on how to use a webcam attach to a router and act as an IP camera. At the end of the article, it show you how to adding authentication to the project.
Saturday, 25 August 2012 12:49

TP-LINK TL-WR1043ND router as a Print Server

This article shows the step on how to setup the TP-LINK TL-WR1043 router as a print server. The USB printer is connected to the USB port of router in order to support print sharing from network.
Wednesday, 22 August 2012 15:49

OpenWRT in VirtualBox

If you are considering to test OpenWRT without a router or you don’t want to flash the router firmware over and over again. Here is the right place for you.

OpenWRT in VirtualBox is an image file run in VirtualBox. By the time I write this article, the VirtualBox & OpenWRT image version are Ver 4.1.20 and 10.03.1 respectively. 

Tuesday, 21 August 2012 21:09

OpenWRT Dynamic DNS

Dynamic DNS allows that your router can be reached with a fixed hostname while having a dynamically changing IP address.

Dynamic DNS is a must if you want to control your devices/network over the internet with dynamic IP address in your Local Area Network. Read this article for more about Dynamic DNS and Port Forward.

OpenWRT come with a package called luci-app-ddns but is not install by default. We must install the luci-app-ddns package in order to enable the Dynamic DNS service.

Samba is a free software re-implementation of the SMB/CIFS networking protocol, Samba provides file and print services for various Microsoft Windows clients.

First, this assumes that you already have OpenWRT installed. Read this article if you haven't upgrade firmware to OpenWRT.

Second, you must have a working USB flash drive attach to router. Read here for installing USB flash drive.

FTP is a method of transmitting or recieving files across the Internet and stands for File Transfer Protocol. This article guide you on how to enable FTP  function on the OpenWRT router.

It is assumed that the router is flashed with OpenWRT. See this article if you haven't upgrade firmware to Openwrt.

The more packages you install on your OpenWRT, the more space you need. It's useful to extend the storage capacity of your USB enabled OpenWRT router.
This article explain how to use a flash drive as a storage installing in TP-LINK TL-WR1043ND router. It is assumed that the router is flashed with OpenWRT. See this article if you haven't upgrade firmware to Openwrt.
Sunday, 19 August 2012 12:13

16 Output Arduino Controller

The is a sketch for Arduino to communicate with computer or embedded device (eg. wireless router) using serial communication.
Arduino Duemilanove have 14 digital IO pins (2 digital IO used by serial) and 6 analog IO pins. Here I coded the analog IO as digital IO, so we can easily get 16 digital IO.
Saturday, 18 August 2012 18:42

WinSCP (Windows Secure CoPy)

WinSCP is an open source free SFTP client, SCP client, FTPS client and FTP client for Windows.

Most people use vi as the text editor during configuration of embedded device. I hate to use vi, in which I have to memorize all the commands. Whereas WinSCP is a GUI (Graphical User Interface) program where you can edit your file like notepad. Additionally you can use WinSCP to download and upload files including settings of permission.

TP_LINK TL-WRT1043ND router and OpenWRT is use in this tutorial.

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