Hello,

 

I am trying to have a serial link between an arduino and a banana pi.

As a basic test, the Arduino is sending "hello" every seconds.

I observe that the reception by the Banana pi is not good. I have tried , several baud rates, /dev/ttyS2 and FTDi adaptor.

The best result seems to be with  the FTDI adapter , at 115200 bps. But I have still a lot of errors, see below.

When I plug the FTDI adapter on my laptop, it works without issues.

 

Do you know what could be the cause of my issues?

 

Thank you

Sebastien

 

 

 

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Is your Arduino using 5V levels? If so, you need a level shifter to not damage your Banana PI which uses 3.3V levels...

On the FTDI USB adapter, I can select 3.3 or 5V.

With 5 V , I have the result posted previously.

With 3.3V, it is worst

21 minutes ago, sebastien35 said:

On the FTDI USB adapter, I can select 3.3 or 5V.

With 5 V , I have the result posted previously.

With 3.3V, it is worst

Is GND securely connected at both ends? I got problems like this when my GND wasnt seated correctly and only TX,RX was connected.

And how long are the TTL-cables - maybe not enough shielding?
How does the arduino and the Babana Pi gets his power?

Thanks a lot! GND was not connected on the USB adapter! Now, with GND connected, it is perfect!

 

And what about the use of /dev/ttyS2? Do you confirm that I have to use 3.3 level. I can't test it for now because I haven't level adapters.

 

 

I didn't use /dev/ttys2...

Yes, @sebastien, you will need a 3.3V-to-TTL level converter, e.g. MAX3232.