1.1 EEPROM Organization

Configuration Zone

An 88-byte (704-bit) zone contains a serial number, counter information, slot read/write and lock words. Within this document, the nomenclature SN[a:b] indicates a range of bytes within a field of the configuration section. The 88 bytes are accessible from within a three-block address space.

Data Zone

A 160-byte (1280-bit) zone splits into five general purpose, read-only, or read/write memory slots of 32 bytes (256 bits) each, that can be used to store keys or other information related to the item to which the ATSHA206A is attached.

Data Sheet Nomenclature

Within this document, the terms “slot” and “block” are used interchangeably to mean a single, 256-bit (32-byte) area of a particular memory zone. Industry SHA-256 documentation uses the term “block” to indicate a 512-bit section of the message input. In addition, the I/O section of this document uses the term “block” to indicate a variable-length aggregate element transferred between the system and the device.

• In this document, the nomenclature mode[b] indicates bit b of the parameter mode.
• Byte ranges are represented as [LSB:MSB]
• Slot indicators are represented by slot[#]