theobroma systems RK3399-Q7, Руководство пользователя

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4.13 Serial Number
Each RK3399-Q7 module has a unique serial number that can be read by software.
In U-Boot, the serial number is contained in the environment variable
serial#
. You can print it using the command:
printenv serial #
Under Linux, it is represented by a simple text file in
/sys
:
cat / sys / firmware / devicetree / base / serial - number
The serial number is fixed in hardware (derived from the eMMC
Product Serial Number
) and cannot be modified.
4.14 MAC Address
By default, the MAC address of each RK3399-Q7 module is a random value derived from the serial number. The properties
of this default MAC address are:
• It is a
Locally Administered Address
: The U/L bit of the MAC address is set to 1
• It is not guaranteed to be globally unique
• The address is fixed for each RK3399-Q7 module. It stays constant across reboots as it is deterministically derived
from the serial number
To set your own
Universally Administered Address
, you overwrite the U-Boot environment variable
ethaddr
. On the U-
Boot prompt, with
XX:XX:XX:XX:XX:XX
replaced by your MAC address:
setenv ethaddr XX:XX:XX:XX:XX:XX
saveenv
The MAC address can be queried from the U-Boot prompt using:
printenv ethaddr
To reset the MAC address to the default value, run:
env delete ethaddr
saveenv
Release v0.2-3-g574c114
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