OK, I "Solved" it by comparing the sdkconfig for the old (working) program and my new one. The key was in the logging format:
CONFIG_LOG_COLORS=y

This caused the IDF Monitor output to appear. (In orange).

Without this setting, I don't see any IDF Log output, for some reason. Perhaps it's there in ...

I'm driving myself crazy here, please help !

I have an IDF project from last year, developed in Eclipse IDF, and if I encounter an unhandled exception crash, the ESP-IDF-Serial Monitor windows in Eclipse automatically decodes the Backtrace, like this;

0x4017c076: _vfprintf_r at /builds/idf ...

Hi,
I need to sample and decode a proprietary protocol. It consists of packets arriving at about 700 bits/ Second, and I will need to capture pulses about 500 uS in duration. (Either a single High pulse, 2 High pulses , or 4 High pulses.)

I will likely use an ESP32-C6, running at 160Mhz. (I want ...

I see your point - sounds like you are on top of this. I look forward to reading your solution - I think you are more experienced here than I am.

From the Espressif Docs:

The LEDC can be used for generating signals at much higher frequencies that are sufficient enough to clock other devices, e.g., a digital camera module. In this case, the maximum available frequency is 40 MHz with duty resolution of 1 bit. This means that the duty cycle is ...

On a 240MHz core, I would have expected that I could easily enter an ISR, toggle a Port Pin and return in 60 cycles, but it's a gut feeling based on other SOCs. But you won't be doing much else with that core.

Perhaps the LED PWM Controller could be programmed to do the job - so no CPU load. But OP ...

I would just use one of the ESP32 timers, set to contintually countdown, and reload. Have it setup to generate an interrupt every time it reaches 0, and then in the ISR toggle the GPIO Pin, directly. This will be short enough to be an acceptable ISR.

Do you know how to use the Timers in this manner ...

Hi, OK, which pin did you connect the +5v to when you used the external PSU? What you are doing should work perfectly well, I do it all the time.

Hi,
since you talk about running a task, I assume you are programming for an RTOS In which case, you would never do this - you would have an interrupt handler (Or callback) pick up date from the SPI, and do something with it - write it to an RTOS Queue for example.

Can you give a little more ...

Hi, can you take a step back? Flash a very simple program into the ESP32 which blinks an LED (And outputs a debug string on the Serial port) Then power it from your breadboard. Does that work?

Apologies if this is in any way offensive - but not knowing your skill level - it's best to start at ...