PD17012GF-055_15 Datasheet, PDF (27/84 Pages) Renesas Technology Corp – SINGLE-CHIP MICROCONTROLLER WITH ON-CHIP PRESCALER, PLL FREQUENCY SYNTHESIZER, AND IF COUNTER FOR CAR-MOUNTED FM/MW/LW RADIO

µPD17012GF-055
Symbol
SEEKUP
(MANU.UP)
SEEKDOWN
(MANU.DOWN)
Description of Functions
While the frequency is being displayed, the key operates as the auto seek/manual seek operation
function key for the receiving frequency. While the clock is being displayed, the key operates as
the clock adjustment key in conjunction with the
DISP
key.
(1) Auto seek operation
While the “AUTO” display is lit, auto seek is in operation.
Auto seek operation is divided into three modes by the setting the current RDS and traffic
information stand-by.
<1> Normal seek mode
Pressing the key starts auto seek from the current frequency upwards ( SEEKUP key)
or downwards ( SEEKDOWN key) in single steps (100 kHz per step in the FM band) and
lights the “AUTO” display.
The presence/absence of a broadcasting station is detected at each frequency. If a station
is detected, the frequency is retained. For a seek operation on LW, even if a broadcasting
station is detected, if the frequency is not multiple of 9, the seek operation continues.
<2> RDS seek mode
While the “RDS” display is lit in the FM band, pressing the key changes the mode to RDS seek
mode.
RDS seek mode operation is the same as normal seek mode operation until a broadcasting
station is detected. However, when a station is found, RDS seek mode operation begins RDS
signal synchronous detection, checks the synchronous status after 200 ms, and if an RDS
station is detected (synchronous RDS signal is detected), the frequency is retained.
If an RDS station is not detected, the seek operation continues.
<3> TP/SK seek mode
While the “TP/SK” display is lit, pressing the key in the FM band changes the mode to TP/SK
mode.
TP/SK seek mode operation is the same as RDS seek mode operation until an RDS
broadcasting station is detected. However, when a station is found, TP/SK seek mode begins
TP/SK signal synchronous detection, checks the RDS data TP bit after 300 ms, and if TP is
detected, the frequency is retained. If TP is not detected, the seek operation continues.
If an RDS station is not detected, the SK pin is checked after 300 ms, and if an SK signal is
detected, the frequency is retained.
If SK is not detected, the seek operation continues.
key operation during auto seek operation is as follows.
Key
Description of Operations
M1
The seek operation is stopped.
|
Call up the content of the preset memory for the pressed key.
M6
Writing is inhibited.
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