It seems I wrote it incorrectly: R1 (100 Ohm) is used to limit excessive current from GPIO3 to the transistor, R2 (100K Ohm) is used to pull the Base pin down to ground in the initial state, and only when there is a Wake-up signal (3.3V) does the Base become active to pull GPIO3 down to GND.The words say "A 100kΩ pull-up resistor (R2) is connected between the collector and the GPIO3"
but the diagram shows R1 100Ω ?
and "The base of the transistor is driven by a signal from the STM32F103 (via PA15 pin) through a 100Ω resistor (R1)."
but the diagram shows the base connected both to the microcontroller and to an 100K resistor to ground. ?
Statistics: Posted by Lee123 — Mon Apr 07, 2025 11:50 am