Using arduino to monitore temperature with lm35

Configuration
1

Hellow there! Im using hass on rpi2 and a lm35 on arduino which is connected on rpi2 via USB.
But when hass is reading it, it shows a value : 55.
the code :

sensor:
  platform: arduino
  pins:
    1:
      name: Temperature
      type: analog

According to arduino playground temperature has to be used with this formula :
temp = (5.0 * analogRead(tempPin) * 100.0) / 1024;
but i dont know how to change standard firmata and i think it easier to do it somehow on hass
Any idea ?

2

You can use a template sensor for this.

4

im new to this, and dont know how to embed template in my configuration. i would appreciate if you write code for my scenario