Does Blink Without Delay Eat Electricity

[mrburnette]

@12ta

My assessment with an ESP32 (and no super accurate means of measurement) is 80mA with loop() churning versus 10mA sat in a delay(). I have seen no discussion around this aspect before despite being intrigued by the potential differences.

'tis a wee bit more complex...

• ESP32 has 2 cores, core_0 and core_1
• core_0 handles all the RF protocols and services
• core_1 handles the Arduino user and IDF wrappers for Arduino core.
• FreeRTOS as a binary file is linked into all Arduino ESP32 projects

So, if you yield() the Arduino core_1, FreeRTOS will service core_0 threads. It is the RF side of things that eat current during transmit; thus stalling core_1 will save on Arduino processing but do nothing for the RF WiFi/BT side of stuff.

ESP32 - using 2nd core

ESP32 Arduino core from here: https://github.com/espressif/arduino-esp32 by default runs the RF/radio/protocols on CORE0 while the Arduino code runs on CORE1. For most scenarios, this scheme works reasonably well. I reworked Neil Kolban's example a few years ago for an article I wrote, I think it simplifies things la bit by using an Arduino multi-tab example: /* This sketch runs the same load on both cores of the ESP32 ArduinoIDE 1.8.5 Linux Mint 18.3 Sketch uses 162569 bytes (…