Quote from Roel on December 20, 2024, 10:07 am

I was discussing with Ron about adding a temperature sensor which reads the actual temperature in the sims cockpit.
Since i use the Airmanager  software i said this must be possible.
Well after some struggling it IS!

I use a DHT11 temp sensor which also can read humidity and send the temp in Celscius as in Fahrenheit.
Using DHT11 | Arduino Project Hub

For use with Airmanager you have to use the "messageport" option, this means adding this library and include it in the Arduino script.
The Arduino then takes over the control of this sensor and send as requested by AM the temp.

Arduino C++ code:

#include <si_message_port.hpp>

#include "DHT.h"

#define DHT11_PIN 14

DHT dht11(DHT11_PIN, DHT11);

SiMessagePort* messagePort;

// Setup section

void setup() {

    // Initialize the message port on Channel A with the callback function

    messagePort = new SiMessagePort(SI_MESSAGE_PORT_DEVICE_ARDUINO_MEGA_2560, SI_MESSAGE_PORT_CHANNEL_A, new_message_callback);

}

// function called everytime a message is received from Air Manager

static void new_message_callback(uint16_t message_id, struct SiMessagePortPayload* payload) {

    if (message_id == 777 && payload != NULL && payload->type == SI_MESSAGE_PORT_DATA_TYPE_STRING) {

        uint8_t* length = payload->len; // returns the length of the payload (not used)

        String command = payload->data_string;// stores the payload in a string <----- modified

        if (command.equals("TEMP") == true){ //equals compares two strings and returns true/false <----- modified

           // read temperature as Celsius

          float tempC = dht11.readTemperature();

            // Send acknowledgment back to Air Manager

            messagePort->SendMessage(777, tempC); // Float

        }

    } else {

        // Do Nothing

    }

    dht11.begin(); // initialize the sensor

}

void loop() {

    messagePort->Tick();  // Regularly calls this to process incoming messages

}

In short what this code does is when the Arduino receives a number of 777 from AM , it sends back the temperature value (in this case in Celsius)

On the AM side the LUA script looks like this:

-- This function will be called when a message is received from the Arduino.
function new_message(id, payload)
-- Do something with the message from the Arduino
print("message received: "..id.." "..payload)
Temp_read = math.floor(payload)
print(Temp_read)
txt_set(txt_TAT, Temp_read)
end

id = hw_message_port_add("ARDUINO_MEGA2560_A", new_message)

-------------------------------------

-- Send a message to the Arduino with id 777 and

-- This function will be called every 2 seconds
function messageport_timer_callback(count)
flipflop= not flipflop --switches the value with every call
if flipflop == true then
hw_message_port_send(id, 777, "STRING", "TEMP")
end
end
timer_start(0, 2000, messageport_timer_callback)

 

In short:

I made a timer which now sends every 2 seconds a request with the value of 777 to trigger the Arduino to send the temperature value.
This value is put in a AM variable to show on the EICAS display

Values received in AM console:

Shown on EICAS

Great idea from Ron
i only have to implement it in the Sim.

-- This function will be called when a message is received from the Arduino.
function new_message(id, payload)
-- Do something with the message from the Arduino
print("message received: "..id.." "..payload)
Temp_read = math.floor(payload)
print(Temp_read)
txt_set(txt_TAT, Temp_read)
end

id = hw_message_port_add("ARDUINO_MEGA2560_A", new_message)

-------------------------------------

-- Send a message to the Arduino with id 777 and

-- This function will be called every 2 seconds
function messageport_timer_callback(count)
flipflop= not flipflop --switches the value with every call
if flipflop == true then
hw_message_port_send(id, 777, "STRING", "TEMP")
end
end
timer_start(0, 2000, messageport_timer_callback)