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gundu
05-06-2012, 12:05 AM
i would start by saying that i read other posts but i still have this doubt for good reason : i have lost five mega16s till date because of setting wrong fuse bits using Xtreme Burner - which is an excellent software for guys like me.

Whenever i write fuse bits to HIGH: D9 or C9 and LOW : FF --> my chip is not responding thereafter. It is very easy to read / write fuse bits using Xtreme Burner but am i making some basic mistake or is there something wrong with this popular software ? Most of the projects i read and try to follow tell me to set the fuse bits as mentioned above. i have read ATMEL doc 2466 also and it seems perfectly fine to disable JTAG( i still don't know fully what this is) and enable external crystal. But what am i missing ? can any body just give a clue pls. Otherwise all my projects using avr studio 4 run perfectly with internal clock in default settings.( i have till now tried with success "blinking led" and motor control ). In default settings the delay functions are not accurate and i want to just get them right. I don't want to spoil my remaining two chips ! Thanks in advance!

i want to add that, i have bought usb programmer and 40-pin board so there is little chance of my hand dirty soldering / loose pins etc.

avinash_g
05-13-2012, 08:16 AM
One external crystal is enabled. The target must have a crystal in it. So once you set Fuse to LOW=FF HIGH = C9, then immediately after that the chip will only RUN if their is a crystal in its XTAL pins other wise it will behave live dead.

Also you must write both the HIGH and LOW fuse at ONCE so check "write" in both the box.

Where you got the 40 PIN board?

gundu
05-20-2012, 01:00 PM
One external crystal is enabled. The target must have a crystal in it. So once you set Fuse to LOW=FF HIGH = C9, then immediately after that the chip will only RUN if their is a crystal in its XTAL pins other wise it will behave live dead.

Also you must write both the HIGH and LOW fuse at ONCE so check "write" in both the box.

Where you got the 40 PIN board?

thank you for response avinash. I bought it from onlinetps.com. i think it has XTAL. i will sure check it again. i have taken a snapshot of the board and attached. u can see the crystal ( KDS 16.000) below the zif socket. the zif has been attached by me . i will try one more time with both high and low selected for writing as u have said.

ANyway , ur software rocks! and ur site super-rocks!