I noticed from journalctl that there was an instruction to add following line to /boot/config.txt:
dtparam=i2c0=on
That helped. Now Mathmatica is able to detect I2C and also SenseHAT.
However there are some errors when reading sensors:
pi@raspberrypi:~ $ wolfram
Wolfram Language 11.3.0 Engine for Linux ARM (32-bit)
Copyright 1988-2018 Wolfram Research, Inc.
In[1]:= sensehat = DeviceOpen["SenseHAT"]
Out[1]= DeviceObject[{SenseHAT, 1}]
In[2]:= DeviceRead[sensehat, "Temperature"]
DeviceWrite::unknownMRAAWriteError: An unknown error occured writing to the I2C bus.
DeviceWrite::unknownMRAAWriteError: An unknown error occured writing to the I2C bus.
DeviceWrite::unknownMRAAWriteError: An unknown error occured writing to the I2C bus.
General::stop: Further output of DeviceWrite::unknownMRAAWriteError will be suppressed during this calculation.
Out[2]= 42.4979 degrees Celsius
In[3]:=
And there are some errors in journalctl as well:
Aug 29 18:00:39 raspberrypi libmraa[873]: libmraa version v1.6.1 initialised by user 'pi' with EUID 1000
Aug 29 18:00:39 raspberrypi libmraa[873]: libmraa initialised for platform 'Raspberry Pi Model B Rev 1' of type 5
Aug 29 18:00:39 raspberrypi libmraa[873]: i2c_init: Selected bus 0
Aug 29 18:01:00 raspberrypi libmraa[873]: i2c0: write: Access error: Remote I/O error
Aug 29 18:01:00 raspberrypi libmraa[873]: i2c0: write: Access error: Remote I/O error
Aug 29 18:01:00 raspberrypi libmraa[873]: i2c0: write: Access error: Remote I/O error
Aug 29 18:01:00 raspberrypi libmraa[873]: i2c0: write: Access error: Remote I/O error
Aug 29 18:01:00 raspberrypi libmraa[873]: i2c0: write: Access error: Remote I/O error
Aug 29 18:01:00 raspberrypi libmraa[873]: i2c0: read_byte: Access error: Remote I/O error
Any idea what is wrong? Here is my Raspberry version:
pi@raspberrypi:~ $ cat /etc/os-release
PRETTY_NAME="Raspbian GNU/Linux 9 (stretch)"
NAME="Raspbian GNU/Linux"
VERSION_ID="9"
VERSION="9 (stretch)"
ID=raspbian
ID_LIKE=debian