Warning: For anyone who started reading, the schematic below is wrong. Hopefully right one is in post #15.
Hi, I finally received the boards from here and tried to set up my deep-sleep/external wakeup ESP8266 (Wemos D1 Mini).
Unfortunately, I have a problem I cannot explain. Here is the reset schematic:
Note that RST has an internal pullup of 10k in the Wemos D1, which I put on the breadboard in the photo for the test.
Note also that D3 also has a pullup of 10k in the Wemos D1, which I soldered on the PCB to open the transistor.
I tested the cap in the detached circuit to be 8.64µF, and the resistance comes up to infinite.
Still, as you can see in the photo, if I connect D0 to GND, the RST voltage drops to something like 0.65V (confirmed with multimeter, its not the shitte “oscilloscope”).
I cannot explain how that can happen. The cap should only let a pulse through, but it just stays at almost GND. A fully set up version works with internal wake up, because it already creates a pulse at D0, but if I use an external wake up that stays low, RST also stays low and the ESP doesn’t boot.
The idea is that wake up pulses can come both from the wake-up timer at D0 or an external switch that is supposed to be able to stay open while the ESP runs (hence the cap). D3 can be used to disable the RST feature to avoid reboots while the ESP is running.
Photos of circuit:
(Perhaps someone could have a look, why I am not able to attach these. Allegedly, they fail a “security test”).