Bluetooth is used for short range wireless communication. Bluetooth is a standard wire-replacement communications protocol primarily designed for low power consumption, with a short range (power-class-dependent, but effective ranges vary in practice.

Here we see how we can connect the bluetooth module with 8051 microcontroller device

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A GSM modem is a wireless modem that works with a GSM wireless network. A wireless modem behaves like a dial-up modem. The main difference between them is that a dial-up modem sends and receives data through a fixed telephone line while a wireless modem sends and receives data through radio waves. Continue Reading…

This is a USB interface board I’ve built around a PIC 18f4550 microcontroller from Microchip. As many of you probably know, I’ve used my computer’s parallel port to connect many things to my computer. However, most laptops don’t have parallel ports these days, so I needed a way to connect things without a parallel port. Continue Reading…


I know there are plenty of USB chargers out there for you to build. But here’s one that doesn’t use a voltage regulator or an IC chip to power it. The basic concept is to use 4 – AAA rechargeable batteries (1.2V a piece) to power the USB and a couple of solar cells to charge the batteries. If you’ve done the basic math you’re probably wondering how 4.8V (4 x 1.2) is going to power a USB device which requires 5VDC. Well that’s actually how I came up with the idea. Continue Reading…