Page 1 of 1

Problem with EUzebox

Posted: Wed Jul 03, 2013 9:51 pm
by isifloh
Hi

I have bought a Euzebox (uzebox with scart ) set and build it.
But now i can't get it to work. 5v and 3.3v are there. The LED does not light up ? Should it ?
I have exchanged the Atmel with a other new programmed one but doesn't help.
Any idear what to check next ?

with nice greetings

Re: Problem with EUzebox

Posted: Wed Jul 03, 2013 11:48 pm
by uze6666
Do you have access to an oscilloscope or a multimeter with frequency counting?

Re: Problem with EUzebox

Posted: Thu Jul 04, 2013 7:44 am
by isifloh
Hi

Yes i have access to an oscilloscope.

With nice greetings

Re: Problem with EUzebox

Posted: Fri Jul 05, 2013 10:57 pm
by CunningFellow
isifloh,

I am looking at the schematic of the euzebox 1.04.

The LED looks like it is directly between 5V and GND. If D1, the red LED is not lighting up then it can only be bad LED or inserted wrong way.

As an aside to this can you just hook up the scope to the xtal to see if it is oscillating at 28mhz.

Re: Problem with EUzebox

Posted: Fri Jul 05, 2013 11:24 pm
by uze6666
The LED looks like it is directly between 5V and GND. If D1, the red LED is not lighting up then it can only be bad LED or inserted wrong way.
That's right, I never noticed it was not connected to a pin of the 644.

Also check if you have power to all pins connected to VCC. Are you sure the bootloader is programmed correctly and the fuses been set?

Re: Problem with EUzebox

Posted: Sun Jul 07, 2013 5:36 pm
by Janka
CunningFellow wrote:As an aside to this can you just hook up the scope to the xtal to see if it is oscillating at 28mhz.
Careful with that, the on-chip oscillator is an icky beast. The extra capacitance of the probe will kill the oscillation (not the oscillator, just the "sinus"). You have to use a 1:100 oscillosope probe or hold the probe tip near the oscillator pins without touching them.

Janka

Re: Problem with EUzebox

Posted: Tue Jul 09, 2013 10:43 pm
by Harty123
Hi,

yes the LED is directly connected to 5V DC. Check the 5V voltage after the 7805 regulator and the input voltage before this regulator. If you want pls send me your EUzebox back. I will check and repair it for free. Don't forget return postage in this case...

Cheers

Harty

Re: Problem with EUzebox

Posted: Fri Jul 12, 2013 9:05 am
by isifloh
hi

sorry for my delay...
the led is now working (the old one was bad).
@Harty123 i will contact you.

with nice greetings
Heinz