Harness the power of our captivating random number generator with ADS1115 and ATmega644
Random wonders: Numbers beyond predictions!
Published Aug 24, 2023
Click board™
RNG Click
Dev Board
EasyAVR v7
Compiler
NECTO Studio
MCU
ATmega644
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
EasyAVR v7 is the seventh generation of AVR development boards specially designed for the needs of rapid development of embedded applications. It supports a wide range of 16-bit AVR microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB. The development board is well organized and designed so that the end-user has all the necessary elements in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyAVR v7 allows you to connect accessory boards, sensors, and custom electronics more
efficiently than ever. Each part of the EasyAVR v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block for the development board. It can use a wide range of external power sources, including an external 12V power supply, 7-12V AC or 9-15V DC via DC connector/screw terminals, and a power source via the USB Type-B (USB-B)
connector. Communication options such as USB-UART and RS-232 are also included, alongside the well-established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets which cover a wide range of 16-bit AVR MCUs. EasyAVR v7 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.
Microcontroller Overview
MCU Card / MCU
Architecture
AVR
MCU Memory (KB)
64
Silicon Vendor
Microchip
Pin count
40
RAM (Bytes)
4096
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 EasyAVR v7 as your development board.
Track your results in real time
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.
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 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
