SI4731-DEMO Datasheet, PDF (5/14 Pages) Silicon Laboratories – Si4731 DEMO BOARD USERS GUIDE

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Si4731-DEMO
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Figure 4. LCD Display in AM Radio Mode
4.2.1. Band Selection
In Radio Mode, the BANDS/0 key is used to switch between the AM and FM bands.
4.2.2. Time/Date Auto Set
Many radio stations broadcast RDS data including clock/time CT information. The AM/FM demo board can capture
this information to automatically set the time and date. In FM Mode, when RDS CT information is received, the CT
indicator will be displayed. The MEM/AL/1 button can be used to update the calendar date and time with the CT
information. CT information is not available on all radio stations and is normally sent only once per minute.
4.2.3. Alternative Frequency (AF) Switching
The AM/FM demo board monitors RDS for alternate frequency (AF) information. When RDS alternative frequency
information is received, the AF indicator will be displayed. If the signal quality of the currently tuned station
degrades, the radio will automatically change to one of the alternative frequency stations.
4.2.4. Tune/Seek
In Radio Mode, pressing the UP/4 or DOWN/8 button for less than 0.5 s will tune the frequency by the preset step
size. Holding the button for longer than 0.5 s but less than 3 s will perform a station seek.
4.2.5. Scan
In Radio Mode, the MSCAN/5 button is used to scan for all valid stations in the selected band and will automatically
save them into preset selections. After a scan operation, the M+/3 and M-/7 keys will cycle through the preset
station list. Scan operation can be aborted by pressing MSCAN/5 again, or by pressing the UP/4 or DOWN/8 key.
4.2.6. Parameter Settings
In Radio Mode, the SET/9 key is used to select the parameter setup menu as illustrated in Figure 5 and Figure 6.
The M+/3 or M-/7 keys will cycle through the available items in the menu. The UP/4 or DOWN/8 keys are used to
set the desired value for each item. Select “Yes” under “Factory Def” to go back to the factory default settings for all
items.
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