A NodeMCU firmware image for GPIO via WiFi.
Just a demo of how to use nodemcu-firmware-build-as-github-action.
See the tutorial repo.
- GPIO4 and GPIO5. All others will be high or at least have some lesser voltage on boot, which may interfere with external electronics. Source: This pinout overview, chapters "Pins used during Boot" and "Pins HIGH at Boot". Summary in the green box at the bottom of the latter.
- Additional Information from Erich Flach about the boot process.
- An experiment with a curve tracer showed that the specific specimen tested would probably be able to not immediately catch on fire if fed even slightly higher voltages.
- Comments have mixed feelings about that, some suspecting semi-official
5V tolerance while others warn about dangers such as:
- Potential long-term damage.
- A possible "bad" production batch at any time in the future that might "merely" fit the datasheet specs, rather than vastly overperforming.
- Potential sneaky (e.g. delayed) side effects/malfunctions that may arise while overpowered and may not be easy to detect reliably.
- Overvoltage on inputs might raise VCC depending on which mode the GPIO pin is operating in and how that mode is implemented in the specific production batch, which may change at any time in the future.
MIT