Secure 8 Click Board™

How Does The Secure 8 Click Board™ Work?

The Secure 8 Click Board™ as its foundation uses the ATECC608B, a cryptographic coprocessor with secure hardware-based key storage from Microchip. The ATECC608B integrates the ECDH (Elliptic Curve Diffie Hellman) security protocol, an ultra-secure method to provide a key agreement for encryption/decryption along with ECDSA (Elliptic Curve Digital Signature Algorithm) sign-verify authentication for the Internet of Things (IoT) market. It includes an EEPROM array that can store up to 16 keys, certificates, miscellaneous read/write, read-only or secret data, consumption logging, and security configurations. It also allows memory-section restrictions in several ways, with a locked configuration feature to prevent changes.

Each ATECC608B contains a unique 72-bit serial number stored in a standard serial EEPROM. Using the cryptographic protocols supported by the device, a host system can verify the signature of the serial number to prove that the serial number is authentic and not a copy. However, these can be easily copied with no way for the host to know if the serial number is authentic or a clone. Like all Microchip CryptoAuthentication products, the new ATECC608B employs ultra-secure hardware-based cryptographic key storage and cryptographic countermeasures that eliminate potential backdoors linked to software weaknesses.

This version of the Secure Click board™ carries two versions of the ATECC608B, thus supporting the standard I2C 2-Wire interface at speed up to 1Mbps (MAHDA) and the Single Wire (SWI) interface (MAHCZ), giving the user the ability to select the desired communication interface for various security applications. While using a Single-Wire interface (SWI), this Click board™ communicates with MCU using shorted UART (RX and TX) lines, which act as a single line with only one trace routed back to the ATECC608B (MAHCZ). Further, UART pins can be used only for SWI communication when this Click board™ is used on a system. When the Single-Wire interface is enabled, the remaining pin is available as a GPIO pin marked as GP and routed to the INT pin of the mikroBUS™ socket as an authenticated output/tamper input.

The Secure 8 Click Board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the Click board™ comes equipped with a library that contains easy-to-use functions and an example code that can be used, as a reference, for further development.

SPECIFICATIONS

PINOUT DIAGRAM

This table shows how the pinout of the Secure 8 Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
NC	1	AN	PWM	16	NC
NC	2	RST	INT	15	GP	General Purpse
NC	3	CS	RX	14	TX	SWI Line
NC	4	SCK	TX	13	RX	SWI Line
NC	5	MISO	SCL	12	SCL	I2C Clock
NC	6	MOSI	SDA	11	SDA	I2C Data
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

ONBOARD SETTINGS AND INDICATORS

SECURE 8 CLICK ELECTRICAL SPECIFICATIONS