RNG 2 Click

How does it work?

RNG 2 Click is based on the RNG90, a secure Random Number Generator (RNG) from Microchip fully compliant with the NIST SP 800-90A/B/C standards. This Click board™ is designed to meet the stringent requirements of modern cryptographic systems, where the strength of generated random numbers directly influences the overall system security. True random number generation is critical in cryptographic applications such as key generation, digital signatures, password creation, nonce generation, random challenges, and initialization vectors. The RNG90 IC addresses these needs by producing a 256-bit random number with each Random command execution, offering a robust security strength of 128 bits. Independently validated for randomness through a NIST-certified laboratory, the RNG90 guarantees trustworthy operation in sensitive applications.

As part of Microchip’s CryptoAuthentication™ product line, it integrates into systems demanding secure, ready-to-use randomness without requiring any additional configuration. RNG 2 Click communicates over a standard I2C interface operating at up to 400kHz, making it simple to integrate with a wide range of host MCUs. It also features a unique 72-bit serial number and advanced hardware-based security mechanisms such as an active shield for protection against invasive physical attacks, tamper detection for abnormal voltage conditions, and temperature-based tamper monitoring. With these features, RNG 2 Click is ideally suited for use in cryptographic systems, password management tools, gaming platforms, cryptocurrency hardware wallets, scientific experiments, and even aerospace and defense technologies, where secure and certified random number generation is a fundamental requirement.

This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this Click board™ comes equipped with a library containing 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 on RNG 2 Click 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	NC
ID COMM	CS	3	CS	RX	14	NC
	NC	4	SCK	TX	13	NC
	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

RNG 2 Click electrical specifications

Software Support

RNG 2 Click demo application is developed using the NECTO Studio, ensuring compatibility with mikroSDK‘s open-source libraries and tools. Designed for plug-and-play implementation and testing, the demo is fully compatible with all development, starter, and mikromedia boards featuring a mikroBUS™ socket.

Example Description

This example demonstrates the use of the RNG 2 Click board by periodically reading and logging random numbers generated by the device.

Key Functions

• rng2_cfg_setup This function initializes Click configuration structure to initial values.
• rng2_init This function initializes all necessary pins and peripherals used for this Click board.
• rng2_default_cfg This function executes a default configuration of RNG 2 Click board.
• rng2_read_random_num This function requests and reads a 32-byte random number from the RNG 2 Click board.

Application Init

Initializes the logger and the Click board driver, then applies the default configuration.

Application Task

Reads and displays a 32-byte random number from the device every second.

Application Output

This Click board can be interfaced and monitored in two ways:

• Application Output – Use the “Application Output” window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.
• UART Terminal – Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.

Additional Notes and Information

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.