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USBAsp circuit problem

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Junior Member level 2
Jun 4, 2011
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i am building a USBAsp based AVR burning kit by using the schematic provided at - USBasp - USB programmer for Atmel AVR controllers

I am using the latest firmware.
I set the fusebits as hfuse=C9 and lfuse=EF (this is defined in the USBAsp makefile)
[but some people have mentioned some different fuse bits. one said hfuse=E9 lfuse=EF]

The two LED s glow but PC and laptop both say "USB device not reognised. A USB device attached to this computer has malfunctioned"

I checked the full circuit. Could find no problem.

I was checking the voltages at different points on the circuit. I found that if I connected the multimeter directly across Pin 7 and 8 of atmega8, it shows 2.5V
When I checked the voltage level at the input pin of the USB port, it shows 5.4V. But sometimes, the voltage rises to 5.8V.

Also when I check the voltage at the pins of the oscillator with respect to ground, I get 0V at both pins. I am using 22pf capacitors. Should the voltage at the oscillator pins be 0V?

I cannot understand what i am doing wrong.
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read that thread.

It seems that my oscillator may be dead. At least I think so since the voltage at both pins is zero
Does anyone have any idea why my oscillator may be dead?
[EDIT] - I was checking the oscillator pins.
A strange thing is happening. If I check the voltage at each oscillator pin with respect to ground, I get 0V. But if I check each pin of oscillator with respect to Vcc, I get 2.3V.
the voltage across ground and Vcc is 5.2V.[/EDIT]

And if the voltage at pins 7 & 8 of Atmega8 is 2.5V, will the uC even work properly? I read its datasheet. it says operating voltage is 2.7 - 5V
Any reason the voltage at those pins is 2.5V?

If I remove the atmega8 from circuit and test the voltage at pins 7 & 8 of 28 pin base, it shows 5.2V.
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