[avrdude-dev] problem with dragon & avrdude, bad signature

[Bob Koutsky]

Hi,

I'm trying to use avrdude 5.3.1 on Linux (Ubuntu Breezy, avrdude is
compiled from source), avrdragon in isp mode connected via USB. When I
try to program ATMega8, I keep getting this error:

$ avrdude -c dragon_isp  -p m8 -P usb -e

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.16s

avrdude: Device signature = 0xff3f00
avrdude: Expected signature for ATMEGA8 is 1E 93 07
        Double check chip, or use -F to override this check.

avrdude done.  Thank you.

The value reported as received device signature keeps changing.
Usually (maybe always), it is composed of various combinations of
bytes 0x00, 0xff, 0x03, 0xc0, 0x3f, suggesting that there's some
pattern in how it is generated.

I double, maybe even triple checked the wiring and tried two different avrs.

Programing ATMega16 in JTAG mode works.

I'm sorry if I'm missing something obvious, as I said, it's been
couple of years I did hardware and it's coming back only slowly 8(

Thanks for any advice,
Bob

--
If the world were going to suddenly turn into a movie without warning,
I wish it would have been one of those boring, talky Merchant-Ivory
ones instead.