[Solved] MySensors WiFi Gateway with NODE-MCU ESP8266 and Capacitive Soil Moisture Sensor : first steps, first errors

[Neo Mod]

Hi everyone,

here I am (again, sorry ) asking for your guidance.

After my initial post about “general ideas” with MySensors and I moved on to the next phase: buying all the components.

I bought two things to start familiarize with this project:

• A NODE-MCU ESP8266 Development Board vers. 1.0 T
• A Capacitive Soil Moisture Sensor by DFROBOT V. 1.0

The idea is to use the NODE-MCU ESP8266 as a WiFi Gateway to collect data from sensor and send it to a controller.

I divided the project in various stages so to easily troubleshoot problems:

1st stage: Setting up the NODE-MCU with Capacitive Sensor and reading data
2nd stage: Setting up the MySensors Wi-Fi Gateway on the NODE-MCU and obtaining “calibrated” data from sensor
3rd stage: Acquiring the data from stage 2 remotely.

Thanks to all the guides and tutorial here I’ve been able to set-up my Arduino IDE software with the library to use the NODE-MCU ESP8266 board.

Following the DFROBOT product tutorial I’ve been able to obtain RAW data from the sensor with this sketch:

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600); // open serial port, set the baud rate as 9600 bps
}

void loop() {
  // put your main code here, to run repeatedly:
  int val;
  val = analogRead(0); //connect sensor to Analog 0
  Serial.print(val); //print the value to serial port
  delay(1000);

}

Now the problem, for me that I’m a total novice to this, is how to set-up the gateway for doing the same thing.

I tried with this sketch, also including the calibration needed to obtain usable values from the sensor but I only come up with an error that I could not understand.

// Enable debug prints to serial monitor
#define MY_DEBUG

// Use a bit lower baudrate for serial prints on ESP8266 than default in MyConfig.h
#define MY_BAUD_RATE 9600

// Enables and select radio type (if attached)
//#define MY_RADIO_NRF24
//#define MY_RADIO_RFM69

#define MY_GATEWAY_ESP8266

#define MY_ESP8266_SSID "mywifissid"
#define MY_ESP8266_PASSWORD "mywifipassword"

// Enable UDP communication
#define MY_USE_UDP

// Set the hostname for the WiFi Client. This is the hostname
// it will pass to the DHCP server if not static.
#define MY_ESP8266_HOSTNAME "sensor-gateway"

// Enable MY_IP_ADDRESS here if you want a static ip address (no DHCP)
#define MY_IP_ADDRESS 192,168,0,200

// If using static ip you need to define Gateway and Subnet address as well
#define MY_IP_GATEWAY_ADDRESS 192,168,0,1
#define MY_IP_SUBNET_ADDRESS 255,255,255,0

// The port to keep open on node server mode
#define MY_PORT 5003

// How many clients should be able to connect to this gateway (default 1)
#define MY_GATEWAY_MAX_CLIENTS 2

// Controller ip address. Enables client mode (default is "server" mode).
// Also enable this if MY_USE_UDP is used and you want sensor data sent somewhere.
#define MY_CONTROLLER_IP_ADDRESS 192, 168, 0, 75

// Enable inclusion mode
#define MY_INCLUSION_MODE_FEATURE

// Enable Inclusion mode button on gateway
// #define MY_INCLUSION_BUTTON_FEATURE
// Set inclusion mode duration (in seconds)
///#define MY_INCLUSION_MODE_DURATION 60
// Digital pin used for inclusion mode button
//#define MY_INCLUSION_MODE_BUTTON_PIN  3


// Set blinking period
// #define MY_DEFAULT_LED_BLINK_PERIOD 300

// Flash leds on rx/tx/err
// Led pins used if blinking feature is enabled above
//#define MY_DEFAULT_ERR_LED_PIN 16  // Error led pin
//#define MY_DEFAULT_RX_LED_PIN  16  // Receive led pin
//#define MY_DEFAULT_TX_LED_PIN  16  // the PCB, on board LED

#if defined(MY_USE_UDP)
#include <WiFiUdp.h>
#endif

#include <ESP8266WiFi.h>

#define CHILD_ID 0

#include <MySensors.h>

// values needed for calibrating the sensor output

int AirValue = 694;
int WaterValue = 344;
int intervals = (AirValue - WaterValue)/3; 
int soilMoistureValue = 0;
MyMessage msg(CHILD_ID, V_LEVEL);
unsigned long SLEEP_TIME = 30000;

int sensorPin = A0;

void presentation()
{
	// Present locally attached sensors here
  present(CHILD_ID, S_MOISTURE);
 }


void loop()
{
	// Send locally attached sensors data here
int soilMoistureValue;
soilMoistureValue = analogRead(sensorPin);

if(soilMoistureValue > WaterValue && soilMoistureValue < (WaterValue + intervals))
{
  send(msg.set("Very WET"));
}
else if(soilMoistureValue > (WaterValue + intervals) && soilMoistureValue < (AirValue - intervals))
{
  send(msg.set("Wet"));
}
else if(soilMoistureValue < AirValue && soilMoistureValue > (AirValue - intervals))
{
    send(msg.set("Dry"));;
}

sleep(SLEEP_TIME);

}

When compiling this code using the MySensors Library v. 2.1.1 ,I receive an error code: I'm sure it's because I'm doing something wrong out of inexperience so I hope if someone among the most experienced users here could help me out...

[mfalkvidd]

@Neo-Mod posting the actual error could be very useful

[mfalkvidd]

Was the error

error: no match for 'operator[]' (operand types are 'inputBuffer' and 'int')

in that case, my google-fu took me to https://github.com/mysensors/MySensors/issues/369 which has been fixed in 2.2.0-beta.

Using library ESP8266WiFi at version 1.0 in folder: C:\Users\Micke\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.3.0\libraries\ESP8266WiFi 
Using library MySensors at version 2.2.0-beta in folder: R:\Documents\Arduino\libraries\MySensors 
Using library EEPROM at version 1.0 in folder: C:\Users\Micke\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.3.0\libraries\EEPROM 

Sketch uses 236,893 bytes (22%) of program storage space. Maximum is 1,044,464 bytes.
Global variables use 32,944 bytes (40%) of dynamic memory, leaving 48,976 bytes for local variables. Maximum is 81,920 bytes.

So either use 2.2.0-beta or wait for the next stable release.

[Neo Mod]

Oh my...sorry, my mistake! I forgot to paste it on the message, thank you for your patience.

Here it is the error: there are some small parts in italian at the end regarding the WiFi Library used. If needed I can translate those.

Arduino:1.8.3 (Windows 10), Scheda:"NodeMCU 1.0 (ESP-12E Module), 80 MHz, 9600, 4M (3M SPIFFS)"

In file included from D:\NeoMod\Documents\Arduino\libraries\MySensors/MySensors.h:200:0,

                 from D:\NeoMod\Documents\Arduino\prova_gateway\prova_gateway.ino:135:

D:\NeoMod\Documents\Arduino\libraries\MySensors/core/MyGatewayTransportEthernet.cpp: In function 'bool gatewayTransportAvailable()':

D:\NeoMod\Documents\Arduino\libraries\MySensors/core/MyGatewayTransportEthernet.cpp:302:35: error: no match for 'operator[]' (operand types are 'inputBuffer' and 'int')

   _ethernetServer.read(inputString[0].string, MY_GATEWAY_MAX_RECEIVE_LENGTH);

                                   ^

D:\NeoMod\Documents\Arduino\libraries\MySensors/core/MyGatewayTransportEthernet.cpp:303:14: error: no match for 'operator[]' (operand types are 'inputBuffer' and 'int')

   inputString[0].string[packet_size] = 0;

              ^

In file included from D:\NeoMod\Documents\Arduino\libraries\MySensors/MySensors.h:28:0,

                 from D:\NeoMod\Documents\Arduino\prova_gateway\prova_gateway.ino:135:

D:\NeoMod\Documents\Arduino\libraries\MySensors/core/MyGatewayTransportEthernet.cpp:304:55: error: no match for 'operator[]' (operand types are 'inputBuffer' and 'int')

   debug(PSTR("UDP packet received: %s\n"), inputString[0].string);

                                                       ^

D:\NeoMod\Documents\Arduino\libraries\MySensors/core/MySensorsCore.h:90:40: note: in definition of macro 'debug'

 #define debug(x,...) hwDebugPrint(x, ##__VA_ARGS__)   //!< debug, to be removed (follow-up PR)

                                        ^

In file included from D:\NeoMod\Documents\Arduino\libraries\MySensors/MySensors.h:200:0,

                 from D:\NeoMod\Documents\Arduino\prova_gateway\prova_gateway.ino:135:

D:\NeoMod\Documents\Arduino\libraries\MySensors/core/MyGatewayTransportEthernet.cpp:305:58: error: no match for 'operator[]' (operand types are 'inputBuffer' and 'int')

   const bool ok = protocolParse(_ethernetMsg, inputString[0].string);

                                                          ^

Più di una libreria trovata per "WiFiUdp.h"
Usata: C:\Users\deimo\AppData\Local\Arduino15\packages\esp8266\hardware\esp8266\2.3.0\libraries\ESP8266WiFi
Non usata: C:\Program Files (x86)\Arduino\libraries\WiFi
Non usata: C:\Program Files (x86)\Arduino\libraries\WiFi
Non usata: C:\Program Files (x86)\Arduino\libraries\WiFi
Non usata: C:\Program Files (x86)\Arduino\libraries\WiFi
exit status 1
Errore durante la compilazione per la scheda NodeMCU 1.0 (ESP-12E Module).

[Neo Mod]

@mfalkvidd thank you! I didn't noticed that among the whole log, my ignorance about this just kicked-in. Thank you again fo your help, I'll read on how to set the beta library and compile again.