In this case I get on :invalid conversion from 'unsigned char*' to 'const char*' [-fpermissive] either cast with (const char *)readtemp() or remove the unsigned keyword. I think the other proposed solution using JSON may be better. What does it print? You should see the JSON string you constructed ...

Make sure your power supply is good. A power supply that drops the voltage a little too low will cause all kinds of problems. If you are using the computer's usb port for power, that might be the problem. If the ramp-up from 0V to 5V on the supply is too slow, I think you'll have boot failures too.

Does readTemp compile? It looks like it might try to return a pointer to a temporary on the stack as an 8-bit value. Perhaps you want it to return unsigned char * and add static to the a[5]. And then you'll want to change the 5 to a 6 and add a null terminator so it can be a c string. And then you m...

Also, in a different thread you said

added 4.7uf capacitor GND <> RST and reset works as expected.

I think that may be related. I removed that (10uF) capacitor at the same time I reduced the 200uF filter on the power supply. One of those fixed the boot issue for me.

I just took a look at https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf table on page 62, which I wish I'd studied earlier. It agrees with what you are saying. Make sure the power supply is good...watch with a scope when it is failing. The dev boards I got from amazo...

I have not used PWM, but my experience has been a few pins on the device I used come up high, or busy doing something, until my code starts running. Most pins come up low(?). I think it is documented, but didn't read it soon enough... I also had issues with restart on a few devices; I believe 200uF ...

Pure software solutions can fail. https://en.wikipedia.org/wiki/Therac-25 Microwave ovens may use a hardware interlock that uses multiple switches when opening the door while running. The third switch in the sequence is a crowbar switch https://en.wikipedia.org/wiki/Crowbar_(circuit) that is suppose...

maybe https://www.cplusplus.com/reference/cstdlib/getenv/ The pointer returned points to an internal memory block, whose content or validity may be altered by further calls to getenv (but not by other library functions). Not sure how that plays out when two getenv calls together here NetworkControll...

Code looks very similar to mine.

1) will it work if you read 10 bytes instead of 64534?
2) does using help?

1/8 inch acrylic box and pcb antenna works in a house through one interior wall or wood floor, 30 or 40 feet. 100 feet and a brick wall is too far.
https://www.amazon.com/gp/product/B07QCP2451/