why are using a slider on your channel 1?
first delete the widget on channel 1 and th trigger, next make the following changes in your code to use the correct data types:
CAYENNE_OUT(1)
{
float Press_bar = (((analogRead(A0)*10)/ 1023) - 0.5); // read adc input pin = 30mv/mbar
// la valeur 0.6 is correction of pressure
Cayenne.virtualWrite(1 ,Press_bar, "analog_sensor", "null");
}
once you upload the code, it will auto create a new green widget with channel 1 on your dashboard. Make it permanent by clicking on +. Add a new trigger to this widget and check if it is working.
Once you have got it working, you will have to change the code so that you don’t hit the trigger limit. Sending MQTT messages within notification limit