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ATmega644p fuses

Discussion in 'AVR' started by Nedix, Dec 13, 2014.

  1. Nedix

    Nedix New Member

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    Hello,
    I have a Nixie schematic with an ATmega644p and it has an external clock oscillator (CMOS/TTL), the one here: http://www.comtec-crystals.com/docs/G/GBA.htm . The oscillator is at 32Mhz, it connects to pin 12 (XTAL2) of the MCU and I need help in setting up the fuses. I looked at several fuses calculators but I still cannot figure out what I have to select for the lfuse.
    Can anyone provide help on this one? I'm a newbie in MCUs so please take it slow with me.
    Thanks
     
  2. kubeek

    kubeek Well-Known Member

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  3. Nedix

    Nedix New Member

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    Not very helpful, of course I used the fuse calculator at that link but, as I previously said, I didn't figure out what the settings should be. I posted the question on another forum and I got an immediate answer; for whoever is interested, the fuses should be:
    lfuse: 0xFo
    hfuse: 0x99
    efuse: 0xFF
     
  4. dave

    Dave New Member

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  5. kubeek

    kubeek Well-Known Member

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    Which settings you couldnt figure out? As I said, you ened to use the external oscillator setting. The start up time depends on application. What else is there to figure out?
     
  6. Nedix

    Nedix New Member

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    Yeah, I didn't know how to match the startup time with the schematic.
     
  7. wkrug

    wkrug Active Member

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    When You're not shure use the longest possible start up time an activate the brown out detection.
    So the Controller and the peripheral chips has enough time to start up when the voltage is stable
     

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