[avr-chat] avrdude : chip not responding

[Vincent Trouilliez]

Hi again,

Just got my ATmega32 chip, fired up avrdude to try and see if the chip
is alive, but avrdude says it's dead ("not responding", he says :-/ ).

I issued this command : 

------
address@hidden:/media/Hoary_Home/vincent/Electronique/avr$ sudo
avrdude -p m32 -c bsd -e -F -E noreset
-----

and got the followinf response from avrdude: 

-----------------------------------
avrdude: AVR device not responding
avrdude: initialization failed, rc=-1
avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100%
0.00s

avrdude: Device signature = 0xff0103
avrdude: erasing chip
avrdude: AVR device not responding

avrdude done.  Thank you.
--------------------------------------

It says it's not responding, but at the same time it gives me the
chips's signature, which I thought was built-in each chip ? I looked at
the part's definition in  avrdude.conf and I don't think it doesn't look
like avrdude could have this 0xff0103 from this file. So it must somehow
have managed to red it from the chip. So the chip is not totally dead I
hope.

I am using brian's cable, and was very careful when building it,
build-quality and pinout... 
The cable is 3 meter long, but before using it, I fed it with a 50KHz
square wave, looking at the output with the scope, and the wave form was
perfectly intact.
I uses the "-E noreset" option of avrdude, which allowed me to witness
that the reset line is indeed being pulled down at the start of the
communication, and goes up (well, almost : 4.82V) at the end.
I also witnessed activity on the MOSI line, which wold indicate that
avrdude does drive the pin, and I also witnessed activity on the MISO
line, which I guess (hope) means that the AVR chip is responding, hence
not dead. I guess the also means that the on-board oscillator is
running, although I have no idea how to check that for sure (can't see
any signal on pins XTAL 1&2).
Sadly my scope isn't a DSO so I can't record the signal to check the
"quality" of the waveform, nevermind check what the data in the frames
actually to interpret them (or ask knowledgeable people to look at them
for me ;o)

I have wired the AVR as simply as possible : Vcc/Gnd (5V regulator +
100nF accross the chip's pins), and left pin 30,31&32 unconnected.
Reset pin gets a simple RC circuit with components values (R:20K,
C:22nF) pulled from the avr-libc PDF documentation.
I didn't put the external quartz, as the datasheet states that the chips
are shipped with the 1MHz internal RC oscillator enabled.

Parallel cable has 1K resistors on clock and data lines but not on the
Reset line, as suggested by Brian on his web site...

Everything is on a bread board...please don't beat me ! I wanted to
quickly make sure I could communicate with the chip before making a
decent board. The bread board has been virtually unused so all contacts
are very much like new.


I am starting to run out ideas on what to check... :-/



Regards,


--
Vince