Harness the power of our captivating random number generator with ADS1115 and STM32F031K6
Random wonders: Numbers beyond predictions!
Published Oct 01, 2024
Click board™
RNG Click
Dev. board
Nucleo 32 with STM32F031K6 MCU
Compiler
NECTO Studio
MCU
STM32F031K6
Enhance your decision-making processes by integrating our innovative random number generator into your applications, ensuring selection fairness and eliminating biases
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Hardware Overview
How does it work?
RNG Click is a random number generator (RNG) based on the ADS1115, 16-bit, I2C-compatible, analog-to-digital converter from Texas Instruments that generates a sequence of numbers or symbols that cannot be reasonably predicted better than by a random chance. In computing, a hardware random number generator (HRNG) or true random number generator (TRNG) is a device that generates random numbers from a physical process rather than using an algorithm. Such devices are often based on microscopic phenomena that generate low-level, statistically random "noise" signals, as in this Click board™. That process is, in theory, completely unpredictable, and the theory's assertions of unpredictability are subject to experimental tests. This is in contrast to the paradigm of pseudo-random number generation, which is commonly implemented by the
software. The heart of the RNG click is the avalanche noise generated from an internal diode of the transistor Q1 (BC846B). Avalanche breakdown is a phenomenon that can occur in both insulating and semiconducting materials. It is a form of electric current multiplication that can allow large currents within materials that are otherwise good insulators. The avalanche occurs when the electric field accelerates carriers in the transition region to energies sufficient to create mobile or free electron-hole pairs via collisions with bound electrons. To achieve that, RNG Click also has a boost converter onboard, based on TPS61041 from Texas Instruments, and creates the +18V power supply for the job. The noise signal, created by the transistors Q1 and Q2, is then amplified with Q3, voltage-limited using the Zener diode, and digitalized using the NC7S14M5X inverter. After that, the string of random ones and
zeros is achieved, which is brought to the ADS1115 - 16BIT sigma-delta ADC from Texas Instruments. The potentiometer P1 is used to set the distribution of ones and zeros as near as possible, which is indicated by the LD2 and LD3 LED diodes. The potentiometer P1 should be set to illuminate the LD2 and LD3 diodes equally. That way, when the single-shot measurement is performed using the ADS1115 over the I2C protocol, the true, 16-bit random number is obtained. This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it comes equipped with a library containing functions and an example code that can be used, as a reference, for further development.
Features overview
Development board
Nucleo 32 with STM32F031K6 MCU board provides an affordable and flexible platform for experimenting with STM32 microcontrollers in 32-pin packages. Featuring Arduino™ Nano connectivity, it allows easy expansion with specialized shields, while being mbed-enabled for seamless integration with online resources. The
board includes an on-board ST-LINK/V2-1 debugger/programmer, supporting USB reenumeration with three interfaces: Virtual Com port, mass storage, and debug port. It offers a flexible power supply through either USB VBUS or an external source. Additionally, it includes three LEDs (LD1 for USB communication, LD2 for power,
and LD3 as a user LED) and a reset push button. The STM32 Nucleo-32 board is supported by various Integrated Development Environments (IDEs) such as IAR™, Keil®, and GCC-based IDEs like AC6 SW4STM32, making it a versatile tool for developers.
Microcontroller Overview
MCU Card / MCU
Architecture
ARM Cortex-M0
MCU Memory (KB)
32
Silicon Vendor
STMicroelectronics
Pin count
32
RAM (Bytes)
4096
You complete me!
Accessories
Click Shield for Nucleo-32 is the perfect way to expand your development board's functionalities with STM32 Nucleo-32 pinout. The Click Shield for Nucleo-32 provides two mikroBUS™ sockets to add any functionality from our ever-growing range of Click boards™. We are fully stocked with everything, from sensors and WiFi transceivers to motor control and audio amplifiers. The Click Shield for Nucleo-32 is compatible with the STM32 Nucleo-32 board, providing an affordable and flexible way for users to try out new ideas and quickly create prototypes with any STM32 microcontrollers, choosing from the various combinations of performance, power consumption, and features. The STM32 Nucleo-32 boards do not require any separate probe as they integrate the ST-LINK/V2-1 debugger/programmer and come with the STM32 comprehensive software HAL library and various packaged software examples. This development platform provides users with an effortless and common way to combine the STM32 Nucleo-32 footprint compatible board with their favorite Click boards™ in their upcoming projects.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Nucleo 32 with STM32F031K6 MCU as your development board.
Track your results in real time
Application Output
1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.
2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.
3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.
Software Support
Library Description
This library contains API for RNG Click driver.
Key functions:
rng_get_voltage- This function gets voltage in millivoltsrng_set_config- This function sets configurationrng_set_vref- This function sets desired vref.
Open Source
Code example
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.
/*!
* \file
* \brief Rng Click example
*
* # Description
* This Click is a random number generator. The device contain potentiometer which control voltage
* so it generates a sequence of numbers or symbols that cannot be reasonably predicted better
* by a random chance. Random number generators have applications in gambling, statistical sampling,
* computer simulation, cryptography, completely randomized design, and various other areas.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes driver, then sets configuration and voltage reference.
*
* ## Application Task
* It reads ADC value from AIN0 channel then converts it to voltage and
* displays the result on USB UART each second.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "rng.h"
// ------------------------------------------------------------------ VARIABLES
static rng_t rng;
static log_t logger;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
rng_cfg_t cfg;
/**
* Logger initialization.
* Default baud rate: 115200
* Default log level: LOG_LEVEL_DEBUG
* @note If USB_UART_RX and USB_UART_TX
* are defined as HAL_PIN_NC, you will
* need to define them manually for log to work.
* See @b LOG_MAP_USB_UART macro definition for detailed explanation.
*/
LOG_MAP_USB_UART( log_cfg );
log_init( &logger, &log_cfg );
log_info( &logger, "---- Application Init ----" );
// Click initialization.
rng_cfg_setup( &cfg );
RNG_MAP_MIKROBUS( cfg, MIKROBUS_1 );
rng_init( &rng, &cfg );
rng_default_cfg( &rng );
}
void application_task ( void )
{
float voltage;
voltage = rng_get_voltage( &rng );
log_printf( &logger, "Voltage from AIN0: %.2f mV\r\n", voltage );
log_printf( &logger, "-----------------------\r\n" );
Delay_ms ( 1000 );
}
int main ( void )
{
/* Do not remove this line or clock might not be set correctly. */
#ifdef PREINIT_SUPPORTED
preinit();
#endif
application_init( );
for ( ; ; )
{
application_task( );
}
return 0;
}
// ------------------------------------------------------------------------ END
