Climate Trend Arrow

Copy the complete code into Arduino IDE or download the sketch. Follow the matching component card before connecting power.

// First Wonder Brain Bots 34 — Climate Trend Arrow
// USB-powered model. Unplug before rewiring. Serial Monitor: 9600 baud.
unsigned long trendInterval=10000;
unsigned long lastTrend=0;
bool haveMemory=false;
float lastTemperature=0;
float trendBand=1.0;
#include <DHT.h>
DHT climate(11,DHT11);bool climateValid=false;float temperature=0,humidity=0;unsigned long lastClimate=0;
bool sampleClimate(unsigned long now){if(now-lastClimate<2000)return false;lastClimate=now;
 float t=climate.readTemperature(),h=climate.readHumidity();climateValid=!isnan(t)&&!isnan(h);
 if(climateValid){temperature=t;humidity=h;}return true;}
void printClimate(){if(!climateValid){Serial.println("CLIMATE UNKNOWN");return;}
 Serial.print("T C: ");Serial.print(temperature);Serial.print(" RH percent: ");Serial.println(humidity);}

void setup(){Serial.begin(9600);climate.begin();Serial.println("Ready. Follow your mission test.");}
void loop(){
  unsigned long now=millis();
  
sampleClimate(now);
if(now-lastTrend>=trendInterval){lastTrend=now;
if(!climateValid){haveMemory=false;Serial.println("UNKNOWN");}
else {if(haveMemory){float change=temperature-lastTemperature;Serial.println(abs(change)<trendBand?"NO CLEAR CHANGE":change>0?"RISING":"FALLING");}lastTemperature=temperature;haveMemory=true;}}
}