Hello I have been using in the past the Arduino Uno Wifi Rev2 for IMU projects and seemed to work correctly. Yesterday I tried to restart some programming on the arduino for an RFID project. I had some difficulties in run an example project from the provider of the RFID read/write module so I decided to take a step back and verify the basic functionalities.
Step1: I connected my arduino board and run the Arduino IDE 1.8.19. The simple blink example of the on board LEDs works and I see the LED "L" orange blinking. (The IDe automatic recognize the COM port)
Step 2: I tried to write a really super basic program to print something on the serial port (below) and read it on the serial monitor but I do not see any message shows up
void setup() {
Serial.begin (9600);
}
// the loop function runs over and over again forever
void loop() {
Serial.println ("Hello World");
delay(1000);
}
I run the same test on a Mac and Windows and I get the same results. Tried to change the cable using the one from the printer but same results. Tried to compile from the online editor but same results. Do you have ever experienced something similar?Any suggestion on what could be?
Do you ever experience anything similar?
I moved your topic to an appropriate forum category @pstabile84 .
In the future, please take some time to pick the forum category that best suits the subject of your topic. There is an "About the _____ category" topic at the top of each category that explains its purpose.
You must perform an "Upload" operation, not a "Compile" / "Verify" operation. Compiling is useful to check whether there are any bugs in your code that would produce a compile time error (or warning if you have them enabled), but it does not update the program that is running on the Arduino board. The program running on the Arduino board is only updated when you perform an "Upload" operation.
Please try this:
Open your "Hello World" sketch in Arduino IDE.
Select Sketch > Upload from the Arduino IDE menus.
Wait until the upload finishes successfully, as indicated by the appearance of a "Done uploading." message on the notification bar of Arduino IDE.
Open Serial Monitor.
Now please reply here on this forum thread with the answers to the following questions:
Did you see the "Done uploading." message on the notification bar of Arduino IDE at step (3), or did you instead see an "An error occurred while uploading the sketch" message?
Do you now see the expected "Hello World" message printed in Serial Monitor?
thanks for your reply. Yes I did the upload and I tried as well to change the delay time for the blink example (from 500ms to 5000ms) and I see the ON/OFF frequency change on the orange on board LED. Could be something with the cable or the default serial port? Anyway to test it?
I tried this test
and no answer on the serial monitor., but when I click on the send button I see the RX LED blinking on the board.
Can happen that I can correctly upload a program but still the serial port might be damaged or malfunctioning?There is a way to test it?
On the Uno WiFi Rev2 pins 0 and 1 are Serial1; the loopback test does not work on those pins.
Below is my theory (meaning I'm not 100% sure if this is correct).
The Uno WiFi Rev2 has different paths between the processor (4809) and the serial-to-usb converter.
The upload is done using updi, the normal communication is done using a UART (DBG_RX and DBG_TX). This can explain that you can upload but your normal Serial is not working properly. I will not be able to advise how to determine what is malfunctioning.
In below image (taken from the schematic (pdf)) the left block is the serial-to-usb converter (32U4) and the right block is the main processor (4809).
RFID uses software serial i just tried code that i use on my uno on the uno r4 wifi guess what it
doesn't work you get a blank serial monitor
but hardware serial works just fine
I don't have a problem the uno R4 dosen't do software serial the same as a uno
you can't use the same pins the op maybe has his code setup wrong.
// Note any pin can be used for TX, but only the following pins
// can be used for RX:
// D0, D1, D2, D3, D8, D14, D15, A1, A2, A3, A4, A5
if hes using software serial to read the RFID
But hardware should work fine for the code he posted
