How to check if an efuse has been burnt?

[cmorgan]

I've looked in esp32/include/rom/efuse.h, soc/esp32/include/soc/efuse_reg.h and bootloader_support/src/efuse.c and it isn't immediately obvious how one can determine if an efuse has been burnt.

Is the developer supposed to first check whether the efuse has been read/write protected and then if not either then read the fuse and look for non-zero values or is there an api based way to do this?

[ESP_Angus]

We don't have a generic API for this in ESP-IDF, although there are some for particular functions (like secure boot & flash encryption), but they tend to be at the "is this feature enabled?" level rather than anything about the efuses.

"espefuse.py summary" will give you this information when connected to a host, though.

Can you explain the use case you have in mind?