Esp32 nano - weird messages over serial

Official Hardware Nano Family Nano ESP32
1

Hello,
Arduino noob here, and I recently started having some weird stuff happen with my nano. Long story short, I put together some mqtt data transfer to a broker, and initially everything acted as I expected, but as I added more soil sensors, I started getting some strange serial messages, and I'm wondering if someone can help me make sense of them.

//wifi stuff
#include <WiFi.h>
const char* ssid      = "";
const char* password  = "";
const char* hostname  = "Esp32Nano";

//mqtt stuff
#include <ArduinoMqttClient.h>
const char  broker[]  = "192.168.0.200";
int         port      = 1883;

const char  topic01[]   = "beckys plants/plant1/soil moisture/";
const char  topic02[]   = "beckys plants/plant2/soil moisture/";
const char  topic03[]   = "beckys plants/plant3/soil moisture/";
const char  topic04[]   = "beckys plants/plant4/soil moisture/";

WiFiClient wifiClient;
MqttClient mqttClient(wifiClient);

//variables
int soil1Moisture = 0;
int soil2Moisture = 0;
int soil3Moisture = 0;
int soil4Moisture = 0;

void setup() {
  // put your setup code here, to run once:

  //start serial, and wait 5 seconds for it to begin
  Serial.begin(115200);
  delay(5000);

  //configure the wifi and begin connection
  WiFi.mode(WIFI_STA);
  WiFi.setHostname(hostname);
  WiFi.begin(ssid, password);
  Serial.print("Connecting to WiFi");

  //send period every second we wait for connection to wifi
  while (WiFi.status() != WL_CONNECTED) {
    Serial.print('.');
    delay(1000);
  }

  //print the local ip address once connected
  Serial.println("");
  Serial.print("Our Ip address is: ");
  Serial.println(WiFi.localIP());

  //configure how these pins will work
  pinMode(D2,OUTPUT);
  pinMode(D3,OUTPUT);
  pinMode(D4,OUTPUT);
  pinMode(D5,OUTPUT);
  pinMode(A0,INPUT);
  pinMode(A1,INPUT);
  pinMode(A2,INPUT);
  pinMode(A3,INPUT);

  Serial.print("Attempting to connect to MQTT broker: ");
  Serial.println(broker);

  while (!mqttClient.connect(broker, port)) {
    Serial.print("Connection failed! Error code = ");
    Serial.println(mqttClient.connectError());
  }

  Serial.println("You're connected to the broker");
  }

void loop() {
  // put your main code here, to run repeatedly:


  //soil monitoring stuff
  soil1Moisture = analogRead(A0);
  Serial.println("Plant 1 Moisture : " + soil1Moisture);
  soil2Moisture = analogRead(A1);
  Serial.println("Plant 2 Moisture : " + soil2Moisture);
  soil3Moisture = analogRead(A2);
  Serial.println("Plant 2 Moisture : " + soil3Moisture);
  soil4Moisture = analogRead(A3);
  Serial.println("Plant 2 Moisture : " + soil4Moisture);

  delay(5000);

  //send plant 1 data
  mqttClient.beginMessage(topic01);
  mqttClient.print(soil1Moisture);
  mqttClient.endMessage();
  
  //send plant 2 data
  mqttClient.beginMessage(topic02);
  mqttClient.print(soil2Moisture);
  mqttClient.endMessage();
  
  //send plant 3 data
  mqttClient.beginMessage(topic03);
  mqttClient.print(soil3Moisture);
  mqttClient.endMessage();
  
  //send plant 4 data
  mqttClient.beginMessage(topic04);
  mqttClient.print(soil4Moisture);
  mqttClient.endMessage();

  Serial.println("Messages Sent");

}

and this is the serial output, or at least part of it:

able

Messages Sent
_conf argument is invalid

d

ntr_enable
nyUSB CDC
Messages Sent
onf argument is invalid

d



Messages Sent
): ledc_conf argument is invalid


io_intr_enable
io_num error
Messages Sent
s: %s(%d): ledc_conf argument is invalid


io_intr_enable
By
Messages Sent
: ledc_conf argument is invalid


gpio_intr_enable
if.github.io/arduino-esp32/webusb.html
Messages Sent
 ledc_conf argument is invalid
2

First step I took after reading through some posts was to open a new sketch that was blank, and download it before then downloading the code above. After re-downloading the code above, I got the same type of weird serial outputs.

3

The compiler doesn't complain, but that is invalid (the "+ soil1Moisture" and the rest like that).

1 Like
4

Thanks for the feedback!

I actually was doing some trial and error in the meantime, and I decided based on some of the messages I was getting back to break the text and the variable into 2 different print statements, and it seems to be working fine now.

That was a strange symptom, but glad it seems to be solved now, thanks again!