LILY-W1 series - System integration manual
UBX-15027600 - R09
Software
Page 38 of 64
C1 - Public
unique MAC address to avoid conflicts. The driver expects the
init_cfg.conf
file to be present in
the /lib/firmware directory to access
.
3.8
Prevent high current in deep sleep
Due to internal configuration settings of the used chipset, the LILY-W1 series modules have an
unintended high current consumption after firmware download. The current consumption for the
deep sleep mode in that case is above 1.4 mA. To prevent the high current consumption, execute the
following command after each power cycle of the LILY-W1 series modules:
3.9
Configuration of transmit power limits
3.9.1
Purpose
The LILY-W1 series modules contain calibration data for the output power in an on-board non-volatile
memory. This calibration data enables the module to achieve maximum transmit power levels that
still pass the required EVM and spectral mask limits. The maximum transmit power levels that can
be used in an end-product also depend on the following:
•
Regulatory domain limits
•
Gain of the antenna and antenna trace design
A configuration file on the host system is used to reduce the transmit power levels as needed.
☞
Transmit power limit configuration files for the reference design (Appendix B) and the
approved antennas are provided by u-blox for each of the certified regulatory domains.
⚠
The correct transmit power limits must be applied to the module after system startup or change
of the regulatory domain.
3.9.2
Transmit power limit configuration file format
A transmit power limit configuration file allows to fine tune the transmit power of the module for a
specific
•
Band
•
Channel
•
Modulation rate
•
Bandwidth (20 or 40 MHz)
The configuration is provided in a text file (txpwrlimit_cfg.conf), which contains specific sections for
each channel in the ISM and U-NII bands to specify the transmit power limit for each modulation rate:
# modprobe command with init_cfg.conf file:
modprobe usb8801 cfg80211_wext=0xf
init_cfg=mrvl/init_cfg.conf
# ifconfig
–a | grep HWaddr
mlan0 Link encap:Ethernet HWaddr 00:50:43:20:12:34
uap0 Link encap:Ethernet HWaddr 00:50:43:20:12:35
wfd0 Link encap:Ethernet HWaddr 02:50:43:20:12:36
iwpriv mlan0 hscfg 7 2