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Or it could just be that I'm stupid and mounted the atmega in the wrong direction.

I'm gonna test right now and post the (hopefully) succesfull result!

The problem is still the same.

I still can't upload!

The atmega may be burnt, so I tried with the one from arduino Uno. But the result is the same.

I must have made a mistake somewhere, but can't find it!

I might have burnt both atmega, but I don't understand how...

The Atmega's included in the NanodeRF kits sold through the shop contain the OptiBoot Arduino Uno bootloader. Make sure you select Uno under Tools>Board in the Arduino IDE prior to uploading. 

Let me know if this hasnt fixed the problem. There is a change you might have a faulty chip but we do test every single chip before their shipped when we flash the bootloader. Have you got another Arduino/emonTx you can test the Atmega328 chip in? 

Alsso have you been able to upload to other boards with the same FTDI cable and IDE? 

Hey!

I've been able to upload the code to the emonTX with the same cable and IDE.

I'll try to test this tonight, and post the result!

Thanks!

So, I've tested the Atmega from my emonBase in my emonTx, and was able to upload code on it.

So it's unlikely a chip problem.

I'll test just after if it's working okay, or if I have some troubles.

But the uploading problem is still strange... Because, even after being able to upload the code using the emonTx, I wasn't able to do anything with the emonBase board. I must have made a faulty connection somewhere. Or the FTDI is plugged in the wrong way. (The ground is at the left of the connector when viewed from top, right?)

Cheers

I have the same problem, when I connect the power line, the emonbase remains off, neither the led switch on. I have upload the code with the emontx and it's all ok, but then, when I connect the chip on the emonbase, there are no signals of life. I have checked the voltage between pin 7 of the 74HCT125 (GND) and the bottom pin of the 3 pads below the 16Mhz crystal and it gives around 3.3v. When I add the wire link between the bottom pin and the middle pin of the 3 pads, I measure 0.96v in each pins. I expected to get 3.3v in each pin, or it's ok so?

Thanks!!

It sounds to me like there must be a short, as the voltage between ground and the middle pin should be 3.3v as described on the build guide: http://ichilton.github.com/nanode/rf/build_guide.html Could there be a soldering short on the board?

It might help if you post a photo of the board (top and bottom) that way we can check that all the components are correct. 

Here You can find the photos of the board:

http://img96.imageshack.us/img96/233/img7691y.jpg

http://img29.imageshack.us/img29/3634/img7696y.jpg

Thanks!!

Ahh, it appears your 74HCT125 is the wrong way around, could that be it? see the correct orientation in this image: http://openenergymonitor.org/emon/sites/default/files/nanodeRF.jpg

ok, very stupid error.

I try tonight and I tell You if it's all ok.

Thanks!!

I've been able to refined down the problem to the 74HCT125.

When plugged out, I can upload any code I want on the ATmega, and the green led lights up in normal operation (normal, but not communicating in any way because of the 74HCT125 absence).

When I put the 74HCT125 back in, I can't upload anythin, and stranger, I've got more than 3.3V between ground and pin 3 (on the socket under the atmega in direction of the USB plug.

Any idea? (I'm currently checking all the traces and solder joints to see if anything might have gone bad!)

Some more informations:

When only the 74HCT125 is plugged in, I measured about 4.25V between ground and 3V3.

I don't think I've heard of this problem before. There is a posibility that being plugged in the wrong way could have damaged the 74HCT125. 

That's also what I'm thinking, also this would be strange. I'm gonna check the datasheet of the 74HCT125...

Do you know how could I breadboard-test the 74HCT125?

Great news!

It look likes the 74HCT125 was burned! I bought another one (local electronic stores are awesome!), replaced the MCP1702 (which I just received this morning), checked the voltages, and everything works great!

Next step: Figuring out the firmware, customizing it to upload data on my server, and everything should be ready to go!