Module counter 

Counter command.

Reads or increments one of the chip’s two 21-bit monotonic counters (Counter0 and Counter1). Counters never decrease and cannot be reset once the data zone is locked.

In this project’s slot model:

• Counter0 backs Slot 5 (PIN hash). It is bumped by 1 on every CheckMac against slot 5, with the convention that the driver rounds the counter up to the next multiple of 5 on successful verification so the user always gets a fresh batch of 5 attempts.
• Counter1 backs Slot 6 (PUK hash). Same mechanism with batches of 10.

Reference: CryptoAuthLib lib/calib/calib_counter.c, constants COUNTER_MODE_READ (0x00), COUNTER_MODE_INCREMENT (0x01).

Enums

CounterId

One of the chip’s two monotonic counters.

Constants

COUNTER_MODE_INCREMENT 🔒

param1 mode bits: increment the counter by 1, then return the new value.

COUNTER_MODE_READ 🔒

param1 mode bits: read the counter without modifying it.