DART-6UL I2C

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DART-6UL - I2C


1 Available I2C buses

List I2C available devices:

root@imx6ul-var-dart:~# ls -l /dev/i2c-*
crw------- 1 root root 89, 0 Dec 28 09:28 /dev/i2c-0
crw------- 1 root root 89, 1 Dec 28 09:28 /dev/i2c-1

System class:

root@imx6ul-var-dart:~# ls /sys/class/i2c-dev/
i2c-0  i2c-1

2 I2C devices per bus

Scan bus 0:

root@imx6ul-var-dart:~# i2cdetect -y -r 0
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --                    

Scan bus 1:

root@imx6ul-var-dart:~# i2cdetect -y -r 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- UU -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: 50 51 52 53 -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --                       

3 Reading / Writing from an I2C device

Variscite includes I2CTools as a part of the default file system build, examples of optional commands:
i2cdump - dump the content of an I2C device
i2cset - write a single character to an I2C device
i2cget - read a single character to an I2C device.

In addition follow 'C' code example as describe in the linux kernel documentation : https://www.kernel.org/doc/Documentation/i2c/dev-interface

4 Variscite's system integrated I2C devices

Note: Do not manipulate Variscite's on-SOM EEPROM, or you will damage the SOM!

When the device is marked with "UU" it says a driver is using it.
Driver with numbers are available.
Variscite devices:

I2C-2 0x38 – focaltech touch
I2C-2 0x68 - RTC On carrier
I2C-2 0x52 - EEPROM on carrier
I2C-2 0x53 - EEPROM on carrier
I2C-2 0x1A – audio codec
I2C-2 0x50 - EEPROM on SOM. Do not write to it!
I2C-2 0x51 - EEPROM on SOM. Do not write to it!