ATtiny416auto fuses & lock
On this chip the fuses sit in the data space (from 0x1280), where the program can read them. They set the watchdog, brown-out, clock, reset pin, start-up time and the boot and application sections. Each bit means what it says: there is no inverted "programmed at 0" as on the classic AVRs. Change a setting and the value below updates; the starting values are the factory defaults. In avr-gcc the fuses are set with FUSES = { ... }; from <avr/io.h>.