Hi all! I am new to this forum, I registered because an error encountered with my DIY arduino.
I am using a Macbook Pro running Arduino IDE under Mac OSX Snow Leopard.
Last week I assembled an Arduino on a breadboard with an ATMega168. Uploaded the bootloader using USBTiny, then adding serial connections with my PL2303 USB-Serial cable and a 74LS04 HEX inverter. I added auto-reset, too. (Also added 10k pullup resistor.)
It worked PERFECTLY! Auto-reset worked perfectly, too. When I pressed the upload button in the IDE, my code uploaded without any bugs. (Selected Duemilanove with Atmega168 from the tools menu).
I used that MCU up in an embedded project, so I had to replace it with another one. I bought a brand new ATMEGA328 MCU. I did exactly the same with it, but did not work.
Tried to burn bootloader with board selected as UNO, and then try to upload as UNO, without any success.
Tried to burn Duemilanove bootloader and upload as Duemilanove, without any success.
Also tried to add different upload speeds in boards.txt (19200,57600,..), without any success.
I was wondering if there's something wrong with my Atmega328p, so I uploaded the Blink sketch to it without bootloader, directly with USBTiny. Blinked PERFECTLY!
The weird thing is coming now:
I tried a loopback test from arduino IDE, while the blink sketch was running, and it worked perfectly. I just got back the bytes I sent.
Then when I saw that there's no problem with my serial connection, I burned the UNO bootloader again. Performed a loopback test again, and it FAILED. I got back nothing.
Before anyone asked: Auto-reset seems to work, because TxLed blinks up right after my code is compiled. But I also tried adding and pressing a reset button manually.
Can it be a problem with the bootloader? Or fuse bits? Or what?
I am trying tricks again and again with no success, and I'm getting a "little-bit" frustrated.
Any help would be appreciated.