Crystal VS clock? Wrong fuse

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Ok, I am not the first person with this problem. I've a Attiny2313 with some wrong bit fuses. I programmed it to ext. clock mode. And I only have some crystal's. Is there an easy way to fuse it to int. RC oscillator?

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You need an external clock. Got a function generator? Another Attiny2313? Just get some kind of signal into the Xtal pin and you should be able to revive your chip

Go electric!
Happy electric car owner / builder

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So I only have to send "1's" and "0's" to the Xtal 1 pin with another AVR. Thanks.

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Quote:
So I only have to send "1's" and "0's" to the Xtal 1 pin with another AVR.

Yes,
AFAIK some programmers need a target clock frequency >= 1MHz.

Klaus
********************************
Look at: www.megausb.de (German)
********************************

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You need a clock speed 4 times faster than your ISP clock (at least).

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I'm using a simple parallel-programmer. With this simple C code:

#include 

int main() {
	DDRD |= (1 << PD1);
	while(1){
		PORTD ^= (1 << PD1); //toggle the PD1 pin for a clock source
	}

}

I 'burned' this code into an Atmega8, but my Attiny2313 does not show any signs of life.

BTW. My ATmega8 is running at 4mhz

Last Edited: Tue. Jul 10, 2007 - 08:29 PM
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Are you sure it is xtal1? did you try xtal2? Did you read the datasheet which one is input?

What frequency are you getting from the live AVR? The ISP frequency must be less than 1/4 of the frequency you put into the dead AVR, so did you try to reduce ISP frequency?

- Jani

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The idea is OK, but if the Mega8 is running on it's default 1MHz RC-oscillator, the frequency of the generated clock is not high enough to meet the criterium: SPI-clock must be less than Fcpu/4.
I don't know what programmer- and programming software you're using, but if you can lower the speed of the programmer, your current setup may work.

As an alternative: program the fuses of the Mega8 to select 8MHz internal oscillator

Nard

Edit: too late ....

Edit2: select 8 MHz, and modify your program to let a timer generate a clock on one of the OutputCompare-pins ...

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tricia, and Ulyana. You can find them https://www.linuxmint.com/

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> What frequency are you getting from the live AVR?
Do not know... I do not have a frequency meter

> The ISP frequency must be less than 1/4 of the frequency you put into the dead AVR, so did you try to reduce ISP frequency?
What do you mean with ISP frequency?

What I have done:
- Clock AVR running at 8mHZ
- Connected the Xtal1 of the 'dead' AVR to the PD1. Yes it is the Xtal1 pin for an external clock.
- Tried to read the osc. bits of the 'dead' Attiny. Ponyprog keep saying 'Device missing or unkown device(-24)'

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Try Edit2 in my previous post ....

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tricia, and Ulyana. You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips