PD17012GF-055_15 Datasheet, PDF (48/84 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
6.1.4 Seek up/down
The operation is started by pressing SEEKUP / SEEKDOWN when the device is in TUNER mode but other
than in SHIFT mode.
The broadcasting station detection operation judges the IF count if the SD level and initialize diodes (AM SD/IF,
FM SD/IF) are ON and terminates the SEEK operation if the condition for “with broadcasting station” is satisfied twice
at the interval of 10 ms. In RDS mode and TP/SK mode, after the condition above has been satisfied, the operations
of detecting the RDS broadcasting station and the traffic information station are performed according to the timing
chart below.
Figure 6-4. Timing Chart in Seek Up/Down (1/3)
(Normal Mode)
MUTE
1
23
40 ms
4
10 ms
23
4
10 ms
5
10 ms
Key ON
Without
station
With Without
station station
23
4
10 ms
5
10 ms
6
290-300 ms
With
station
With
station
1 MUTE first-out and beep output
2 Frequency division ratio setting
3 PLL lock wait
4 SD stability wait (1)
5 SD stability wait (2)
6 MUTE last-out output (490-500 ms in band edge detection)
46