I see UART traffic on the programming port, but R11 is a pull-down to GND for IO0. This needs to be a pull-up to 3V3
Board mod to follow short term
Does not affect programmer if R11 is left unloaded
Leave R11 empty and IO0 will pull high via ESP32 pull-up
Flashing the device is a success
Document photo of programmer setup below. No components are loaded yet. Programmer is supplying the voltage and EN/IO0 signals.
DS18B28 functions
BME280 based I2C port works
Adding Power supply circuit now