i2clib

Rust i2c manipulation library designed for Raspberry PI devices. Initial creation made for AZDelivery OLED i2c displays

Simple Example

This library is written in Rust, so in this example we will use the Rust language and the Cargo tool. Another language ? Without Cargo ? Let's see the other examples

Generate a project with Cargo by running $ cargo init in your shell at the directory you chosen earlier. Edit "Cargo.toml" file and add the following part:

[dependencies]
i2clib = { git = "https://github.com/antoninhrlt/i2clib" }

Now edit your main file: "src/main.rs", it should look like this after:

use i2clib::*;

fn main() {
    // nothing to show for the moment
}

Good instructions for good usage

• What's my screen's i2c address ?

  To find your screen's i2c address, simply check on your screen an inscription "0x...". Considering being on a 7 bits base, perform this calculation: (example with 0x78 found on your screen, but written as 8 bits hexadecimal number)

  0x78 = 01111000 (as 8 bits in binary)
  = 0111100 (as 7 bits in binary) = 0x3c (as hexadecimal)

  (from https://passionelectronique.fr in French)

• What is my screen's port ?

  Open a terminal on your Raspberry PI and type: ls /dev/ | grep "i2c-" and you get for example: i2c-1, so "1" is your port !

• How to connect my screen ?

  These are the two most important GPIO ports that we will use.

  

  (picture taken from abelectronics.co.uk , thanks a lot)

  And now connect by cables your screen to the Raspberry PI following this scheme:

  

  (picture taken from the book "AZ-Delivery 1,3” OLED I2C", thanks a lot)

  By evidence, you can select another port to connect the black cable (ground) if it's a "ground" port, and also for the 3V3 port you can choose another, like emplacement 17, as long as it's a 3V3 port. But the two GPIO ports presented above are the only possibilities to work with i2c.

• How to enable i2C on Raspberry PI ?

  The following instructions are a tutorial to explain how to connect a screen to your Raspberry PI (only with a Linux system like Raspbian). During this tutorial I will considering you don't have any monitor connected and all can be done with the simple shell.

  • Turn on your Raspberry PI.
  • Type this in the terminal: $ sudo raspi-config, go to "3 Interface Options" and then "P5 I2C", enable it by press enter two times. Screenshots here
  • Exit the Raspberry's config menu by press "echap".
  • Restart your Raspberry PI.
  • All done !

Other Examples

With the C language

// nothing to show for the moment

Without Cargo but Rust

// nothing to show for the moment