Skip to content

Water sensors

Only if you bought them separately

This guide describes the setup procedure of the Atlas Scientific probes in case you bought them separately. If you have purchased a Water Station, you don't need to do this.

Setup

Manually switching circuits to I2C mode

If the drivers are new normally they come configured in UART mode so we need to change them to I2C mode.

  1. Remove circuit from Tentacle shield.
  2. Put the circuit into a breadboard.
  3. For PH, DO, ORP and EC: Short the PGND pin to the TX pin using a jumper wire.
  4. For RTD (temperature): Short the PRB pin to the TX pin using a jumper wire.
  5. Power the device (connecting GND and VCC)
  6. Wait for LED to change from green to blue (UART→I2C) or from blue to green (I2C→>UART).
  7. Remove the jumper wire from the PGND (or PRB respectively) pin to the TX pin (Do this before removing power!).
  8. Remove power (VCC).
  9. Apply power (VCC).
  10. The device is now in the new mode (repeat all steps to switch back to previous mode).

Official documentation

Atlas Doc

Connection to Smartcitizen Kit

After connecting the Tentacle 3 to the SCK power your kit and if youre connected to the shell the autodetecition message should look similar to this (depending on the connected drivers and probes):

Urban board detected
Enable Atlas Temperature
Enable Atlas PH
Enable Atlas Conductivity
Enable Atlas Specific gravity
...

Sensor calibration

Make sure to follow our sensor calibration guide for the water sensors.

Raspberry setup

  1. Install raspbian
  2. Enable I2C with raspi-config, reboot, upgrade.
  3. Install packages and reboot. 
    sudo apt-get install python-smbus i2c-tools
  4. Connect the shield with the pi off.
  5. Test I2C 
    sudo i2cdetect -y 1
  6. Code example https://github.com/AtlasScientific/Raspberry-Pi-sample-code/blob/master/i2c.py