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Topic: [SOLVED] Set Low Fuse Bit, Now Can't Program over ISP (Read 6 times) previous topic - next topic

dc42

PS - have you checked for solder bridges on the XTAL1 or XTAL2 pins of the mcu?
Formal verification of safety-critical software, software development, and electronic design and prototyping. See http://www.eschertech.com. Please do not ask for unpaid help via PM, use the forum.

Aakash

@dc42 Thanks for the suggestion. I'll check for bridging tomorrow. I'll have to order a 100ohm resistor to test out the clock signal feeding. So that'll take a few days. I'll reply back with results then.

Thanks again everyone.

dc42

#22
Nov 17, 2012, 11:26 am Last Edit: Nov 17, 2012, 02:50 pm by dc42 Reason: 1
If you haven't got 100 ohms, try with 1K or whatever value >100 ohms you do have - it might work.

[EDIT: the datasheet for that resonator very helpfully gives the impedance at various frequencies. Based on that, at a clock frequency of 1MHz, even a 10K resistor may not be too high a value for it to work.]
Formal verification of safety-critical software, software development, and electronic design and prototyping. See http://www.eschertech.com. Please do not ask for unpaid help via PM, use the forum.

Aakash

#23
Nov 17, 2012, 09:05 pm Last Edit: Nov 18, 2012, 12:21 am by Aakash Reason: 1
@dc42 - I attached various screenshots of logic analyzer outputs. The file names are as follows:


  • RAW_SOURCE: the output of connecting the analyzer directly to Pin 9 of the clock source Arduino, which is running your code, through a 1.5K resistor.

  • XTAL1: The analyzer output on CKOUT due to connecting Pin 9 of source Arduino to XTAL1 pin on m328p through a 1.5K resistor

  • XTAL2: The analyzer output on CKOUT due to connecting Pin 9 of source Arduino to XTAL2 pin on m328p through a 1.5K resistor




I connected both the Arduino, m328p, and the logic analyzer to a common ground throughout these tests.

How should I proceed?

Thanks again!
Aakash

Nick Gammon

Try running my "chip detector" sketch:

http://www.gammon.com.au/forum/?id=11633

That generates a clock signal on pin 9 as well in case you need it.

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