- The CPU checks the state of this port regularly to detect a change in this
signal.
- The Output terminal is controlled by the Output Port of the IC103. When
the Port output is L, the transistor (Q503) on the following stage is OFF
and, when the output is H, the transistor is ON. This transistor has open
collector output and it controls external equipment via external pull-up.
15.9.2. Clear Setting SW
- The CLEAR SETTING SW (SW101) is connected to the Input Port of the
GPIO. It is usually at H level and goes to L level when the SW is pressed.
- The CPU monitors this Input Port regularly and, if it detects that this SW
is pressed longer than the set period, the setting values other than the
RTC are returned to the factory settings.
16. TERMINAL GUIDE OF ICS, TRANSISTORS AND
DIODES
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