HDMI I2C hacking n fooling around
This simple tool dumps the content of the I2C EEPROM chip in the EDID of a display / TV.
There really isn't anything particuliar with that, i2c-dump in the i2c-tool collection will work at least as well.
This more a little example on how you can communicate with I2C devices using HDMI/VGA/DVI port of your computer.
Before running that, you will need to install i2c-dev, and then loading the module i2c-dev with sudo modprobe i2c-dev
As it's names tells, it is meant to read an adxl345 accelerometer.
It uses combined read/write transaction without stop, so we should use
struct i2c_msg tx_msg, rx_msg;
// we should configure rx_msg and tx_msg
struct i2c_rdwr_ioctl_data exchange = {
{tx_msg, rx_msg}, /* ptr to array of simple messages */
2 /* number of messages to exchange */
};
ioctl(file, I2C_RDWR, &exchange);
from i2c-dev lib.
So yeah, you will need the libi2c-dev lib. Il just had to type sudo apt-get install libi2c-dev
on my computer.
In the future, this tool will also gives an FFT decomposition of the sampled signal, and maybe even to help balancing a rotating shaft.