PD178016GC-051_15 Datasheet, PDF (57/96 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCONTROLLER WITH BUILT-IN PRESCALER, PLL FREQUENCY SYNTHESIZER, AND IF COUNTER FOR AUTOMOTIVE FM/MW/LW RADIO APPLICATIONS

µPD178016GC-051
4.5 Detection of Front Panel Detachment
(1) Panel state detection timing
When the high level state of the panel input signal is detected ten times in a row, the panel is assumed to have
been detached (see <1>). The time required to assume that the panel has been detached is 10 ms × 10 + Time
required for sensing = 100 ms or longer but less than 110 ms.
The timing at which the replacement of the front panel is detected is the same as above.
10 ms
PANEL
High
Low
Detached
Front panel
state
Replaced
<1>
: Timing at which the panel input signal is sensed
(2) Operations performed when front panel detachment and replacement are detected
When the front panel is judged to have been detached, the power is turned off irrespective of the setting of the
POWER key.
When the panel is judged as being installed, the setting of the POWER key is checked and, if it is judged to
be OK, the power is turned on.
(See Sections 4.1 and 4.2 for details on power state transitions.)
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