PD17012GF-058_15 Datasheet, PDF (31/94 Pages) Renesas Technology Corp – PLL FREQUENCY SYNTHESIZER AND CONTROLLER FOR FM/MW/LW TUNER (AUTOMOBILE APPLICATION)

µPD17012GF-058
2.6.3 Momentary keys
The functions of the momentary keys are summarized below (in alphabetical order).
Momentary key
Description
ALARM
This key can be used only for setting alarm mode.
This key is effective when the IGNITION pin is at the low level and DISALARM initial setting diode = 0.
See Chapter 3 for details.
BAND
The BAND key is used to switch the reception band.
This key is effective when the current mode is radio, radio-monitor tape, or radio-monitor CD mode.
When the key is pressed, the reception band is switched sequentially as follows.
FM1 FM2 FM3 MW1 MW2 LW
However, inhibited bands are skipped. They are specified by the AREA1, AREA2, and AREA3 initial setting
diodes (to specify reception areas) and the DISFM3, DISLW, ENFM, and ENMW2 initial setting diodes (to
specify reception bands).
The band display and last channel vary during band switching within the same type of band (FM1 → FM2
→ FM3, MW1 → MW2).
The BAND key becomes ineffective in tape and CD modes.
CD
Each time the CD key is pressed, the output of the CDOUT pin (pin 45) is inverted.
Using the CDOUT output makes it possible to implement an application such as described below:
Turning on/off a transistor switch connected to the CDSET pin according to the CDOUT output can switch
on/off the CD mode according to the state of the CD key.
CDOUT 45
VDD
K1
KS7
29