VAR-SOM-AM43 I2C: Difference between revisions

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= Variscite's system integrated I2C devices =
= Variscite's system integrated I2C devices =
{{note|Note:Don't manipulate Variscite's on-SOM EEPROM, or you will damage the SOM!|info}}
{{note|Note:Don't manipulate Variscite's on-SOM devices, or you will damage the SOM!|info}}
When the device is marked with "UU" it says a driver is using it.
When the device is marked with "UU" it says a driver is using it.
<br/>Driver with numbers are available.
<br/>Driver with numbers are available.
<br/>Variscite devices:
<br/>Variscite devices:
<br/>I2C-0 0x1B Audio Codec  
<br/>I2C-0 0x1B On SOM Audio Codec - do not alter
<br/>I2C-0 0x24 PMIC
<br/>I2C-0 0x24 On SOM PMIC - do not alter
<br/>I2C-0 0x50 On-SOM EEPROM - do not alter
<br/>I2C-0 0x50 On-SOM EEPROM - do not alter
<br/>I2C-0 0x51 On-SOM EEPROM - do not alter
<br/>I2C-0 0x51 On-SOM EEPROM - do not alter
<br/>
<br/>
<br/>I2C-1 0x38 Capacitive Screen
<br/>I2C-1 0x38 Capacitive touch panel
<br/>I2C-1 0x68 RTC
<br/>I2C-1 0x68 RTC

Revision as of 13:08, 24 December 2015

Available I2C buses

List I2C available devices:

root@varsomam43:~# ls -l /dev/i2c-*
crw-------    1 root     root       89,   0 Dec 24 13:50 /dev/i2c-0
crw-------    1 root     root       89,   1 Dec 24 13:50 /dev/i2c-1

I2C devices per bus

Scan bus 0:

root@varsomam43:~# i2cdetect -y -r 0
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- UU -- -- -- --
20: -- -- -- -- UU -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: 50 51 -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --                      

Scan bus 1:

root@varsomam43:~# i2cdetect -y -r 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --                    

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

Variscite's system integrated I2C devices

Note:Don't manipulate Variscite's on-SOM devices, 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-0 0x1B On SOM Audio Codec - do not alter
I2C-0 0x24 On SOM PMIC - do not alter
I2C-0 0x50 On-SOM EEPROM - do not alter
I2C-0 0x51 On-SOM EEPROM - do not alter

I2C-1 0x38 Capacitive touch panel
I2C-1 0x68 RTC