Getting Started
Page 28
2.7.1.2
Standard Linux I2C Tools
Carry out the following steps to access the BMC.
»
Find out the number of the SMBus the BMC is located on by listing the I2C devices:
»
Look up the SMBus address of the BMC in
Chapter 5.2 SMBus/I2C Devices on page
. In this example, the BMC address is
0x4D
(7-bit notation).
»
Display the devices of the SMBus (i2c-9) to look for the BMC address
0x4D
:
»
In this example, the BMC has the address
0x4D
, i.e. it is located on SMBus number 9.
»
There might be several SMBuses in the list. If you do not find the BMC address on
the first SMBus, list the devices on the other SMBuses. For SMBus 1 (i2c-1), for
example, use this command:
»
When you have found out the address of the BMC and the number of the SMBus
you can dump the registers of the BMC using this command:
»
Read out values using command
i2cget
:
In the following you can find some examples showing how to use the watchdog:
Setting the watchdog time to 10 seconds (
0x64
):
This procedure is also applicable to other SMBus devices.
$
sudo i2cdetect -l
(small l not number 1)
[...]
i2c-x smbus SMBus adapter SMBus adapter
[...]
For example:
i2c-9 smbus SMBus adapter SMBus adapter
$
sudo i2cdetect -y 9
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- 08 -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 1f
20: 20 21 22 -- -- -- -- 27 -- -- -- -- -- -- -- --
30: -- -- 32 -- -- -- -- 37 -- -- -- -- -- -- -- --
40: -- -- -- -- 44 -- -- -- -- -- -- -- -- 4d -- --
50: -- -- -- -- -- -- 56 57 -- -- -- -- -- -- -- --
60: 60 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: 70 -- -- -- -- -- -- --
$
sudo i2cdetect -y 1
$
sudo i2cdump -y 9 0x4d
$
sudo i2cget -y 9 0x4d
$
sudo i2cset -y 9 0x4d 0x14 0x64 w
