Hello folks,
i have build sangaboard 0.3 a week ago and from that time i am trying to get it working, didnt find any failure on the board itself. When i connect the board to the programmer, i have no problem to burn bootloader, but when i connect the board to usb it is not recognised at all, not in windows nor in linux, i also tried to put differend chip where i already uploaded the firmware with the same result.
As you can see from the pictures, i didnt find Atmega32U4-AU, so i used MU version instead and created adapter for it, there are no short circuits.
Do you have any idea what could be the problem ? I am using USBasp programmer.
The chip is taken from Arduino Leonardo with 16Mhz crystal, may there be some fuse bits that needs to be changed ? Would appreciate if you share the bits on your working board.
Sharing actual fuse bits from the chip:
C:\Users\Blapa\Desktop\usbasp.2011-05-28>avrdude -p m32u4 -c usbasp -U lfuse:r:-:i
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.02s
avrdude: Device signature = 0x1e9587 (probably m32u4)
avrdude: reading lfuse memory:
Reading | ################################################## | 100% 0.01s
avrdude: writing output file “”
:01000000FF00
:00000001FF
avrdude: safemode: Fuses OK (E:CB, H:D8, L:FF)
avrdude done. Thank you.
I have not got any answer, but to clarify what you mean: you can burn the bootloader, but you cannot then load any firmware because the board does not show up on USB at all? Or you can load the firmware as well, but then it does not work as a Sangaboard?
You got it correct, I can burn the Bootloader, but when i connect the board, nothing happens, the computer doesnt recognise that “anything” was connected. Even when i upload the firmware to the chip if i solder it on arduino board and then put it back to Sangaboard, same result.
There are different USB ports with different functions on v0.3. You clearly have a lot of experience, so I assume you are not using the wrong USB?
Yes, the USB port is the “data” port, so should be ok. Didnt try to use the other one as there is “pwr” port and the USB-A port is “optional” as i understand so didnt try either, dont even know what the USB-A is used for, i just happen to have spare around, so i soldered it, i may check it. anyway, i will try to dive into the fuse bits configuration, i suspect the configuration for “stock” Atmega32U4 is different from the one thats embedded on Leonardo board. Did not yet find what is the configuration, thats why i would love to see from someone who has a working one. Also, will try to check once more the data lines from USB to the chip.
About the data lines… from the Assembly guide and this picture it seems that the diode is correctly soldered, but if i check the leonardo board, where they use almost the same approach to connect the USB data port, the diode is flipped… so i am a bit confused about this…
Edit: just double checked and the diode is correctly soldered. Same as on leonardo, was misleaded by perceptional position of the diode, but the leads are ok.
