Info - Persistent Latch Read

The Persistent Latch Read mode of the INFO command allows for reading the state of the persistent latch. This is useful to verify the state of the persistent latch when a key authorization has been connected to that latch.

For the ATECC608A-TFLXTLS device this command is only valid when the Secure Boot option is enabled. When this option has been enabled the command will read back a “1” if the SecureBoot operation has completed successfully otherwise a “0”. This status also indicates the ECC Primary Key (Slot 0) has been authorized or not.

Table 1. Input Parameters - Info Persistent Latch Read

Opcode
(1 Byte)

Mode
(1 Byte)

Param
(2 Bytes)

Data
(0 Bytes)

Description
0x30 0x04 0x00 00 Read back the value of the persistent latch.
Table 2. Output Response - Info Persistent Latch Read
Name Response Description
Response 0x00 00 00 00 Successful return value if persistent latch is disabled or if value to persistent latch has been written successfully.
0x00 00 00 01 Successful return value if persistent latch is enabled
0xXX Single byte error code upon failure