LG G3100 User Manual page 134

You can set the light-up duration you want whenever you press a
key.
You can set the rate of serial port to 19200bps for using the
application between PC and fax.
You can set the rate of serial port to 115200bps for using PC
application for GPRS call and Data call.
You can select the language you need displayed.
You can set the brightness of LCD you want
by pressing U , D .
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