Arduino data transmision not working

Hello guys,
I am building a meteorologic station with ethernet. I am using these sensors:

DS18B20
DHT21
BMP180
UVM-30A
maplin rain gauge with flip-flop circuit

Everything was fine (alone) until I put it in one circuit. The DS81B20, UVM-30A and DHT21 are working but the other two are not responding. I don't know what it might be and I was working like ten hours and still nothing. I need your help. More info at

Thanks

Jakub_Nagy:
Hello guys,
I am building a meteorologic station with ethernet. I am using these sensors:

DS18B20
DHT21
BMP180
UVM-30A
maplin rain gauge with flip-flop circuit

Everything was fine (alone) until I put it in one circuit. The DS81B20, UVM-30A and DHT21 are working but the other two are not responding. I don’t know what it might be and I was working like ten hours and still nothing. I need your help. More info at

https://www.instructables.com/id/Arduino-Meteo-Station-With-Ethernet

Thanks

Yo dawg, where’s the code?!? Can’t help much without that.

Shot in the dark:
1 - Check that the libraries are compatable
2 - Check electrical connections
3 - Check amount of SRAM required by all the libraries and code put together

Write/find simple code for the sensors that don't work.
See if you can get one working on it's own.
Leo..

code is working , but when I complete circuit and test one of the programs it don't work. In code of BMP180 is this:

Serial.println("Pressure Sensor Test"); Serial.println("");

but when I connect it with 10m cable it just says (serial monitor) "Pr" just fragment i don't know what it is. This thing happend with other library too.

Jakub_Nagy:
...but when I connect it with 10m cable it just says (serial monitor) "Pr" just fragment i don't know what it is. This thing happend with other library too.

What cable are you using. How did you connect it. What are the values of the pull up resistors (both sides).
10 meters over standard I2C, with standard 10k pull up?
Not going to happen.
Try if the sensor works with short wires.
Leo..

code

test_sensors_2_.ino (4.43 KB)

Success! Without 10m cable it's working. Do you think the 10K pull up resistors should do it?

ok, working thanks