8.4 Read Operations in the Security Register

The Security register can be read by using either a random read or a sequential read operation. Because the EEPROM and Security register share a single Address Pointer register, a “dummy write” must be performed to correctly set the Address Pointer in the Security register. Therefore, a random read or sequential read must be used as these sequences include a “dummy write.” Bits A7 through A5 are “don’t care” bits as these fall outside the addressable range of the Security register. Current address reads of the Security register are not supported.

To read the Security register, the device address byte must be specified with the opcode 1011b (Bh) instead of the opcode 1010b (Ah). The Security register can be read to read the 64-bit serial number or the remaining user-programmable data.