python-3.xraspberry-pidevicei2cidentify

Is there a way to programmatically detect type, manufacturer, name and/or description of i2c device on raspberry pi


I have a raspberry pi connected with multiple i2c devices and want to be able to programmatically work out the type, manufacturer name, device name and/or description for each device on the i2c bus.

Is there any way to do this? Can it be done in python?

I can already get the ID numbers with python code the does essentially the same as i2cdetect, but it doesn't give any information that tells what each device is.

That means I have to manually dig through data sheets and then still have to disassemble the hardware and test with each individual device as the only one connected, to identify which device is at which ID, since some devices can be customized by altering their factory ID.

Putting it together in the first place was a huge job that I don't want to repeat, so I would rather have a way to identify each device programmatically. Does anyone know how or if this can be done? Does i2c protocol lend any support for that?

Could it be done indirectly, ie. is it possible to power down or otherwise temporarily mute or disable an i2c compatible HAT while the Raspberry Pi is running and then rescan the i2c bus and identify which ID no longer shows up?


Solution

  • No, the I2C bus is not designed for this.

    The only way to do something like this is to have the knowledge of the possible addresses for each type of device stored somewhere, together with a way of detecting whether it's really that particular device. Some devices (such as the BMP/BME sensor family) have a ID register that can be used for this, but others don't have that. There are even devices (such as displays) that don't even support reading any data from them.