If you look at the circuit, it seems like there is a connection between GPIO16 and RST.
Some say it’s because GPIO0 left floating and thus low at boot, causing it to start up in flashing mode.
I had a batch of ESP-01 boards. About half of them wouldn’t wake up after deep sleep - no matter what I tried. I’m afraid it could be a hardware issue with these cheap knock-offs.
I use these boards to mount my ESP12F on. They pull GPIO0 high with a built in resistor(not so hard you can’t get in to flashing mode with an external resistor). Have worked very well. For deep sleep to work only need the RST-GPIO16 connection added.
Sorry, yes Zenzay42 was quick to point that out. How have you physically connected it all together? What is the nature of the 3.3V power supply? What it the output of the logger? If you aren’t getting any logs over wifi try a serial connection.
Set the IP manually and allow fast connect. It can easily take 10s for wifi to connect with a good signal.
Your circuit picture doesn’t show many of the necessary pins being pulled high or low. In the bare esp12f there is a 12K resistor between RST and VCC pulling RST high. Measure that resistance if you can. Can you manually wake it if you connect a wire momentarily between RST and GND? It might be better to disconnect the RST to GPIO16 connection first to try this.
Does the LED flash on at all?
There certainly do seem to be a lot of people with problems. I buy my esp8266 from the cheapest sellers on Aliexpress and have never had any problems but that’s just anecdotal evidence.
I’ve seen the topic you’re referring to before posting this topic.
I want to make a thermometer with battery supply, esp8266 can easily measure the supply voltage, but esp32 cannot, so I chose esp8266.
I have made another post about this issue How to measure voltage the chip is getting on esp32?
Both can measure the voltage across the cell using adc pins and voltage divider depending on the voltage of the cell. Your code didn’t have sensors in it. What sort of batteries are you using?
Oh, I wasn’t suggesting you to solder on the resistor. That was just for Mahko_Mahko as there was some interesting pictures in there that we had seen before.
esp8266 can measure supply voltage without using adc pins and voltage divider,no need to add any external circuit hardware,Just add the following code:
At first, I left the GPIO0 pin floating. Later, after listening to everyone’s opinions, I added a 6.8K resistor between GPIO0 and VCC, but it still didn’t work.
For testing, I use a 3.3V regulated power supply to the chip.