Arduino DUE vs. DUE-CH340

[Giovi Alex]

Hi all,

Out of curiosity, I bought another Arduino board from Aliexpress. It's a clone labeled DUE-CH340 (no "Arduino" label anywhere).

I'm getting some issues using that board and I don't understand if it's a faulty board (as I'm suspecting) or just a compatibility issue, and I wish to be sure before to open a case with the seller.

I can program the board and it seems to work in the Altair-duino, using the switches (however the first time I loaded the "kill the bit" it didn't save what I entered... strange).

If I connect it to the Putty terminal, it hangs: yellow LED "L" on and all the Altair-duino LEDs on. If I then press reset it comes back to life and I can load the programs from the SD card (I have to say the other board works flawless in the same environment).

Does anybody here have some clues about that?

cheers,

Giovi

[Chris Davis]

I tried the CH-340 early in the project and it didn't work so well.  I still have one of my old Altair-Duinos in my shop with a CH-340 in it.  Try removing the 470 ohm resistor and 47uF capacitor and see if that works.   If not, you can wire an external reset button to GND and the reset pin on the Due.

[Giovi Alex]

Chris,
do you mean to remove those components from the Due board? There are a couple of SMD capacitors - both 47 uF (I'm not sure what to remove), but I can't find any 470 ohm resistor on it...

I discovered the Reset trick and I planned to put a reset button, but if there's a workaround, it would be better, of course.

[Chris Davis]

R73 and C1 on the main circuit board.