Hi all.

Now my problem's solved. After all it's about power supply.

Sorry Andi... I didn't listen to you in the first place (http://www.8052.com/forum/read.phtml?id=47231).

I used single line of 5V from my PC which I thought would provide enough power for the system. Now, I apply separate power supply for my scanner and my decoder and they're fine :))

Thanks all.

Regards,
~fhy