Blynk Widget Terminal as Serial Monitor

How can I make the Blynk Widget terminal as a remote serial monitor? I just need whatever on the serial monitor to appear on the widget terminal. Thanks

It’s quite easy. You have to connect the Rx and Tx pins on the board together with a jumper.
This will need to be removed when you upload new code, unless you use OTA.

Take a look at this post for the code:


Thank you so much for this, I only have a small problem it says that Widget_terminal is not declared in this scope im not very sure on how to solve this issue thank you.

You need to add this line near the top of your code:

Widget_Terminal terminal(V1);

and change V1 to whatever virtual pin you attach your terminal widget to in the app.

you will also need to add this line of code near the top of your sketch too:

bool terminal_output_enabled = true;


I have a problem, when i put a jumper cable in the rx and tx, the whole device just goes haywire where it stops working. The rx and tx are the 1 and 0 digital pins right?

It depends on your board, you haven’t shared what board you are using.

It would be helpful if you shared details of your full hardware setup and your full code (correctly formatted with triple backticks of course).


i’m just using arduino uno with esp 8266-01 shield. I already established a serial connection.

Well, judging by the code that you posted (then wisely deleted because it didn’t have the necessary triple backticks), you are doing lots of things wrong.

Maybe you should study what I said earlier.


@acecanacan as you’ve started a new topic and posted your original code there (which still has multiple issues that I guess may be beyond your current skill level to resolve), I’m closing this topic.

If you ever get your code working with Blynk and still require your serial output to be mirrored to the Blynk terminal widget then come back here and re-read this topic to see how it should be done.

For anyone interested, the new topic is here: