I'm still using Arduino IDE 1.8.9 and the esp32 Boards extension (by espressif Version 3.3.0) with an ESP WROOM 32 module. A small test sketch with nothing but void setup() and some Serial output does not work, unless I add some delay between Serial.begin and the first Serial output. This test v…

[image] michael_x: a delay of more than 300 ms is required, because after an upload the output in an already open Serial Monito This is more like a delay in switching between the upload, which happened through an external program, and restoring the connection to the Monitor. As you noted, pre…

ESP32 delay required after Serial.begin

Projects Programming

Deva_Rishi August 3, 2025, 12:04pm 10

The baudr-rate could also be adjusted in the Serial.begin() and the monitor.

What to do. It must have something to do with the ESPtool not releasing the port on time in that case.

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ESP32 delay required after Serial.begin

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