LDmicro Forum - Fuse Settins for ATmega

Fuse Settins for ATmega (by David R)

Hi,
I am trying to use ATMega for the first time, can any body
give me the best fuse settings to get started with.
I am using ATMega32 with 16mhz Xtl and AVR_isp_Mk2.

Regards
David.

Fri Nov 6 2009, 04:05:57

(no subject) (by Jonathan Westhues)

The factory default should be okay, except disable JTAG, set CKSEL = 1111 for a crystal oscillator, and set CKOPT = 0 for the most robust (but also highest power/EMI) oscillator mode.

Fri Nov 6 2009, 22:07:52

(no subject) (by Evan Raftery)

Do those settings also apply to the Atmega 128?

Sat Nov 7 2009, 00:14:05

(no subject) (by Jonathan Westhues)

Yes. But the ATmega128 has one extra byte of fuses, where 'M103C compatibility should be disabled, and the watchdog timer should be disabled.

Sat Nov 7 2009, 00:18:07

(no subject) (by sushil)

i ve tried it.this solves my problem of speed but after this my software can not communicate or recognize device any more.
i think i need to design new programming circuit for it.
the circuit i have is just a direct connection of pc parallel port with device with just a buffer in between with no crystal. plz see attached file: description of programming circuit and software i am using. is it ok or should i buy some good programming kit. my company will pay for that so i can buy one if you suggest any good one

thanks n regards
sushil

Wed Nov 11 2009, 06:37:23, download attachment schematic.gif

(no subject) (by Jonathan Westhues)

Perhaps you are disabling serial programming (i.e., setting SPIEN to 1)? That would explain your problem.

If you change only the fuses for CKSEL and CKOPT, and leave all the others at their factory defaults (not all zero or all one, at the factory defaults), then your micro will work.

Wed Nov 11 2009, 06:44:43

(no subject) (by sushil)

will u suggest me how to unlock my device myself else i am going to market for new devices.
thanks a lot for help and sofware

Wed Nov 11 2009, 07:05:21

Help me (by Sudirman)

I'm using ATmega16 with 12MHz crystal and to use DU ISP for V3.0 downloader and AVR Studio 4 software downloader.

After I make program the SET and the Reset, compiled and downloaded to ATmega16 but does not function set and reset.

How I can do be so function set and reset to work in ATmega16?

Thank you.

Mon Feb 28 2011, 07:49:26, download attachment Set Reset.ld

no subject (by simon)

Hi Sushil

Your ATmega is ok . If you program fuses for external cristal ,the comunication with PC will not work if your atmega dont have cristal conected . The oscilator of atmega must be functional in order to comunicate with computer .

success

Mon Feb 28 2011, 11:26:16