Monday 5 September 2011

Revamp Theme for Blackberry Curve 8520

Curiosity led me to test a Blackberry Curve 8520 I really liked it and now it's mine. All mine !!! :P
Recently I tried to add some features to my phone so I can see the Blackberry OS in action. And I've managed to find a great theme for my phone and I wanted to share with you guys.
Screenshot:

Download link: Click here
Source: Deviantart.com
If you guys found other cool BB themes or apps please leave me a comment. :)

Friday 29 April 2011

Unlocking ATMEGA64 fuse bits

     I replaced an ATMEGA64 microcontroller with a new one. And I said that it would need a basic test program to run (blink a led on a certain pin). Although I had a 8 Mhz external crystal I observed that the LED was blinking slower than expected so I said to myself that it had to be something related to the fuse bits.

     After a small search on the web I found this AVR Fuse Calculator. And I played around with these fuse bits and also programmed them to my MCU and finally I ended up locking it.

I've set the fuse bits as followed: LOW: C0 HIGH: 99 EXTENDED: FF.

     So here's the solution for those interested or maybe for those experiencing the same problem:
     After some reading I understood that the fuse bits are low active. So I programmed my MCU (with CKSEL = 0000 and SUT = 00) to run on a external clock source that should be connected on pin XTAL1.
     And in order to unlock my ATMEGA64 I had to generate a square wave using another MCU (I chose an AMTEGA8) and to connect it to pin XTAL1 of my ATMEGA64 (do not remove your crystal or the caps) like so:

     Load the .hex file to ATMEGA8 after compiling this code:


int main()
{

DDRB = 0xFF;
while (1)
{

PORTB = ~PINB;
asm volatile("nop");
asm volatile("nop");
// _delay_ms(1000); // Uncomment this line to test flicker
}
return 0;
}


     By using this code it will generate on any pin of PORTB on ATMEGA8 a square wave with 1 MHz frequency. This will allow any of you to reprogram the fuse bits of your locked AVR microcontroller.

     In my case in order to make my ATMEGA64 to work properly I've chosen the following fuse bits: LOW: EE HIGH: 99 EXTENDED: FF.

Best of luck in unlocking your own microcontrollers.

Sunday 13 March 2011

Programming AVR microcontrollers in Eclipse

     Well I presume that most of the newbie AVR programmers (just like me) started writing code in AVR Studio 4. I found this software that has a very unfriendly text editor with few customizable options and I've decided to use Eclipse for developing my future programs.

     If some of you want to make the same thing I will guide you step by step how to setup Eclipse in order to build AVR code with avr-gcc compiler.

     By the way this solution has been tested on a Windows 7 - 64bit operating system.

Install the following:
- WinAVR (my version: 20100110)
- Java Runtime Environment (latest 64-bit version)
- Eclipse Galileo (64-bit version for Windows)

After installing all of these, launch Eclipse.
- Go to: Window -> Preferences -> Install / Update -> Available Software Sites -> ADD:
http://avr-eclipse.sourceforge.net/updatesite/

- Press OK.
- Now go to: Help -> Install New Software -> choose the source you earlier entered and choose: CDT Optional Features -> AVR Eclipse Plugin (just that).
- Restart Eclipse.

That's it. ;)
Happy AVR coding.

Monday 17 August 2009

Wednesday 24 September 2008

Monday 22 September 2008