I am trying to make a detection system using Arduino UNO and ESP32-CAM. I am using two PIR detectors, if a specified PIR sensor detects movement, then I will take a picture with the ESP32 and send it by mail to the owner of the house, if the two sensors detect movement I won’t do anything, this is to avoid false positives, because I want to detect small animals crawling over the floor. So, I dont know if any of you have faced something similar , but I am wondering if it wouldn’t be dangerous, for the safety of ESP32-CAM, the connection through a current amplifier, using a NPN transistor, between an Arduino pin and the GPIO13 of the ESP32 cam…I think it wouldn’t need the transistor because the current coming out from Arduino is 40 mA,higher than the 5 mA coming out from the PIR sensor, but I haven’t found anywhere the minimum current necessary to the GPIO number 13, and I dont know what it’s the best option to choose, and I don’t want to destroy my ESP32-CAM module 🙁
Have anyone used an out of the Arduino UNO as an entrance to ESP32?.
Thanks a lot for your help and ideas!!!
What kind of signal you want to send from the Arduino to the ESP32-CAM?
There are different scenarios.
- If you want to send data, the safest way is to use a level shifter to convert a 5V signal into a 3.3V signal.
- ESP32-CAM pins work at 3.3V, however, they are 5V tolerant. So, in theory, it shouldn’t be a problem.
- Alternatively, the safest choice is to use the transistor if you just want to send “ON” and “OFF” signals.
If you only have one ESP32-CAM to experiment with, maybe the third is the best option – just to be safe.
Hi Sara, thanks a lot for your quick answer.
According to your answer I think my scenario will be the third one, because I just want to send an interruption to the ESP32-CAM, a HIGH level coming out from Arduino UNO directly to the GPIO13, in order ESP32-CAM can take a picture of the moment a dog is passing by. I will let you all know if it finally works :).
Then, tell me how it went.
By the way, have you taken a look at the project with the PIR motion sensor + ESP32-CAM + Telegram?
Hi Sara!, not yet, but definitely I will take a look, these two actions, can be done at the same time with the same code?, I mean, send an e-mail and send a message in Telegram with the same Arduino code?, I guess it’s possible but I haven’t examined the code yet. Thanks again for your help and support.
I haven’t taken a look at that, but it should be possible. 😀
I was only recommending that tutorial because it seems related with what you want to do and you might have found it useful.
Hi Sara, there was no problem about the use of a transistor, it worked properly. Obrigado!