Have been programming Arduinos for several years now with only infrequent short-lived upload problems. Now I have one that I've spent 3 days on to no avail.
First the good news - uploading to an UNO via usb works without problems.
I did the loopback test using the FTDI cable and it worked without problems.
What I cannot do is upload via the FTDI cable. I have 3 of them and loopback works with all 3, but none of them change the problem of not being able to upload. I have tried with several 328 chips with no luck.
I did a little experiment - uploaded to an UNO successfully and failed via FTDI cable to a different 328. I then swapped the chips. Same problem - uploading to the UNO works fine and via FTDI does not. I don't believe the chips/bootloaders are the problem.
I have updated the drivers for FTDI. I'm running WIN7 and IDE 1.5.8 - have tried with 1.0.6 and even 22 with same results.
Perhaps I'm too close to it to see the problem but I am stumped.
Uh... What model of Arduino is failing? You only say you swap a "386" chip between an UNO and some unspecified configuration. I would be tempted to guess you have a "Breadboard Arduino" and that it is wired incorrectly. Did you include a crystal? Did you include the auto-boot capacitor? Did you use the right value of pull-up resistor on the Reset pin?
This is an "Arduino" that I have built to embed in a project. I built it in January and have uploaded to it 15-20 times with no problem whatsoever.
I'm very comfortable with electronics and computers as I have BS and MS in EE and a career in IBM. I've built dozens like it without problems.
Now please go back and read my original post to see if you can help me.
Thanks
Have you installed the auto-reboot cap between the DTR line and the reset pin of the 328? Also try disconnecting any section of the circuit that might be connected to pins 2 and 3 (Rx and Tx) of the 328 as it can sometimes cause problems.
Without an idea of the actual error you are getting I am afraid there is not much else we could suggest.
The error I'm getting is in the title of this thread.
The schematic I use when building these is the one that comes with the Ardweeny which does have the cap you mention.
I have uploaded to this arduino many times up until a few days ago. I can't for the life of me think of what might have changed.
Found the problem - in the same 5v circuit for the arduino, I have the receiver board for a 4 channel remote at 433mhz. When I disconnect power to the receiver board, upload works without problem. I scoped both the 5v and the arduino oscillator and applied .1 and .01 uf caps to the 5v with no improvement. So it's not clear yet exactly what the real problem is but I now know how to work around it. I tried it 5-6 times with and without power to the receiver board and it definitely works well when no power attached to the receiver board.
Sounds like possible RF noise coming in on the power lines from the RF board.