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I2C VGA Adapter

tags: debian, i2c, vga, hdmi, dvi, hardware, electronics, logic level converter, linux 2012-07-07 08:41 by sre

For one of my projects I’m making heavy use of I²C devices. For development it would be nice to connect them to my notebook and develop and debug the sourcecode natively.

Luckily I remembered that all common display connection standards (VGA, HDMI, DVI) have an I²C control channel. In the linux kernel these pins are exported as I²C device by the graphic card driver. For example my intel driver exports 8 I²C devices.

So the only hardware needed to use an I²C device on my notebook is a cheap VGA cable. After cutting it in half we have two I²C adapters. I decided to create one cable for 5V I²C devices. This one is already done after cutting the cable in half. I soldered a jumper wire connector on the four needed wires and removed the others.