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@allObjects
Detail about KN6 (NPN) and K42 (PNP) transistor arrrays:
KN6 (NPN) transistor array bases for vibration motor and speaker are driven via current limiting resistors. K42 (pnp) transistor array bases for display back light and heart rate monitoring LED are directly driven by the IO expander port pins and have most likely an integrated resistor to limit base current and with that limiting the load on the IO extender output ports (pins) P5 (8) and P7 (10).
Typical of driver transistor arrays is the Base-Emitter resistor to shut the transistor on floating base. It is possible that both KN6 and K42 contain such resistors.
Details about pull-up resistors on buttons 1 thru 3:
The three (3) resistors in upside-down of uppercase L layout 'above' the antenna / to the right and above the SJK 32.000 Xtal on the black flex cable connection side are pull-up resistors for the physical push buttons BTN1, BTN2 and BTN3. Their value is so high that touching the hot end with the probe of the multi-meter for measuring the voltage has the same effect as briefly pushing the related button.