> For the complete documentation index, see [llms.txt](https://ruggedboard.gitbook.io/ruggedboard/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ruggedboard.gitbook.io/ruggedboard/lib-mraa-and-upm-sensor-libraries/example-programs-for-communication-protocols/i2c.md).

# I2C

**To interface an I2C bus.**\
The I2c module module has a number of different ways of interacting with the i2c bus

```
x = m.I2c(0)
x.address(0x77)

# initialise device
if x.readReg(0xd0) != 0x55:
  print("error")

# we want to read temperature so write 0x2e into control reg
x.writeReg(0xf4, 0x2e)

# read a 16bit reg, obviously it's uncalibrated so mostly a useless value :)
print(str(x.readWordReg(0xf6)))

# and we can do the same thing with the read()/write() calls if we wished
# thought I'd really not recommend it!

x.write(bytearray(b'0xf40x2e'))

x.writeByte(0xf6)
d = x.read(2)

# WARNING: python 3.2+ call
print(str(d))
print(int.from_bytes(d, byteorder='little'))
```