Thanks for the thoughts and explanations. Adding the 0.1 uF cap to EN solved the issue --- turns out i missed it in the datasheet's reference design.

(and yes - it is a proper Espressif device)

I managed to scope TX0 during an anomalous startup. The device was powered and running. As soon as i started miniterm.py (not idf-monitor, so without RTS POR) --- the ROM msg (nominally at the default 115200) came through at 76800. Then, the EARLY LOG and application serial came through at the desir...

i am testing a custom pcb. I am using CH340C for USB<->UART. Flashing at 921600 baud consistently works. However, once the program is running (e.g., hello_world idf project or Arduino GetChipID) i have UART communication issues. With CPU set to 240 MHz and serial set to 115200, the program prints a ...

I use a hw timer at 100 Hz with xSemaphoreGiveFromISR and I buffer data in a task pinned to core 0 with xSemaphoreTake . The buffer is implemented as a ring buffer. In the Arduino loop function (a task pinned to core 1), I write new elements in the ring buffer to the internal flash using LittleFS. A...