I am subscribed to few variables and certain actions are performed on the basis of the response I get from the ubidots using callback function
for example: If a get a payload '5’ from the source /v1.6/devices/IoT_Project/Fire/lv then the pin 4 is made high for a sec.
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i=0;i<length;i++) {
Serial.print((char)payload[i]);
}
Serial.println();
String strTopic = String((char*)topic);
if (strTopic == "/v1.6/devices/IoT_Project/Fire/lv")
{
if((char)payload[0] == '5')
{
digitalWrite(4, HIGH);
delay(1000);
digitalWrite(4, LOW);
} } }
Now, I want to get the value of payload and save it in a variable and I don’t know how to do it if the length of payload is ‘2’ or ‘3’.
I hope someone can help me here.
Thanks