SI4840-DEMO Datasheet, PDF (6/22 Pages) Silicon Laboratories – Si4840/44 DEMO BOARD USERS GUIDE

Si4840/44-DEMO
Human Interface:
There are 8 keys for controlling the demo board as shown below.
TREBLE/AL
BASS/TMR
DE/SPC
POWER/BAND
SETTING
MONO/ST
DOWN/VOL-
UP/VOL+
Each key can have a different function under each operating condition:
 Time mode: Radio function is disabled. LCD displays time. Buttons can be used to set time, alarm, etc.
 FM/AM/SW Radio mode: Tuner IC works in power up mode. Radio function is enabled. LCD displays the radio
station parameters. Buttons are used to adjust radio settings.The functions of the buttons are summarized in
Table 1. The FM/AM/SW radio parameters which can be configured are listed in Table 2.
Table 1. Key Function Description
Button
Time Mode
Tuner Off
FM/AM/SW Radio Mode
Tuner On
Hold Time < 1s
POWER/BAND
Hold Time > 1s
None
Enable radio
Change between FM, AM, and SW (there are 1 FM
band, 1 AM band and 8 SW bands)
Disable radio function and enter Time mode.
(Radio parameters will be saved to MCU.)
DE/SPC
None
FM mode: Change De-emphasis, between 50 and
75 us.
AM mode: Change channel space, between 9 kHz
and 10 kHz.
BASS/TMR
Enter or quit setting
menu.
Decrease Bass/Treble level by 1 step.
TREBLE/AL
Enable or disable the
alarm function; enter or
quit alarm setting menu.
Increase Bass/Treble level by 1 step.
UP/VOL+
Hold Time < 1s
In setting menu, change
the current time/alarm
parameter by one unit per
each press.
In radio setting menu, change the current parameter
by one unit per each press. In radio working mode,
increase volume 1 step per each press.
Hold Time > 1s
In setting menu, change
the current time/alarm
parameter automatically.
In radio setting menu, change the current parameter
automatically.
In radio working mode, increase volume level auto-
matically until to maximum.
DOWN/VOL-
Hold Time < 1s
In setting menu, change
the current time/alarm
parameter by one unit per
each press.
In radio setting menu, change the current parameter
by one unit per each press. In radio working mode,
decrease volume 1 step per each press.
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Rev 0.1