USB to Serial Adapter

Hi, I have an Arduino nano connected with an Arduino uno with a FT232rl USB to Serial Adapter. The nano sends numbers in a loop to the uno. I have the Uno connected to my PC to see the output with the serial monitor. The Uno is supposed to print out the numbers sent by the Nano. The program on the Nano works fine. I have checked it by plugging it directly into my PC and looking at the output with the serial monitor. However, when I plug the Nano in the USB port of the adapter, it doesnt start sending(Tx does not blink).

Any idea why?

I think those things need to be connected to a USB host to work. The PC knows how to be a USB host, but the Nano doesn't.

Thank you for your answer. Is there any way that an arduino can be a usb host?

ahobbit: I have an Arduino nano connected with an Arduino uno with a FT232rl USB to Serial Adapter. The nano sends numbers in a loop to the uno. I have the Uno connected to my PC to see the output with the serial monitor. The Uno is supposed to print out the numbers sent by the Nano.

I can't figure out what exactly is connected to what. Can you make a simple pencil drawing showing the connections and post a photo of the drawing.

If you want to connect an Uno to a nano you just need 3 wires to connect Rx Tx and GND. You will probably need to use SoftwareSerial (or AltSoftSerial or NeoSWSerial) on the Uno so as to leave pins 0 and 1 free. Note that Rx must connect to Tx on the other board

...R

ahobbit: Is there any way that an Arduino can be a USB host?

Yes, you would need a USB Host Shield.

Point is - it is obviously the completely wrong way to approach your problem.

In fact, while Robin's point is valid - you have failed to explain what you are attempting to connect to what, underlying this is the XY problem: Why would you use two different Arduinos in any case? :astonished: