Achieve a secure and efficient way to store sensitive data using AT24CM02 and STM32F469II
Store. Retrieve. Repeat.
Published Aug 23, 2023
Click board™
EEPROM 3 click
Dev Board
Fusion for STM32 v8
Compiler
NECTO Studio
MCU
STM32F469II
Our solution leverages EEPROM memory for seamless integration of over-the-air updates, simplifying software deployment and enhancing the agility of your technology
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Hardware Overview
How does it work?
EEPROM 3 Click is based on the AT24CM02, an I2C serial EEPROM from Microchip. The EEPROM density is usually expressed in bits, so exactly 2,097,152 bits are organized in units or words of 8 bits, which gives 262,144 bytes of data memory. Furthermore, the EEPROM is organized in so-called pages. One page holds 256 bytes, and there are 1024 pages (1024 pages x 256 bytes = 262,144 bytes total). Having insight into how the memory cells are organized is important for Write and Erase operations. One of the key features of the
AT24CM02 IC is the Error Detection and Correction scheme (EDC), which allows error correction by utilizing six additional bits internally assigned to a group of four bytes. This protection scheme can correct some types of bit errors, staying transparent to the end user. The bit comparison and error correction are done internally. EEPROM 3 Click uses a standard 2-Wire I2C interface to communicate with the host MCU, supporting clock speeds of up to 1MHz. The I2C address can be selected over the ADD jumper, where 1 is set by
default. Several read modes are available, including current address read, random address read, and sequential address read. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the PWR 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.
Features overview
Development board
Fusion for STM32 v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different 32-bit ARM® Cortex®-M based MCUs from STMicroelectronics, regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over WiFi. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, Fusion for STM32 v8 provides a fluid and immersive working experience, allowing
access anywhere and under any circumstances at any time. Each part of the Fusion for STM32 v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector.
Communication options such as USB-UART, USB HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. Fusion for STM32 v8 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
Type
8th Generation
Architecture
ARM Cortex-M4
MCU Memory (KB)
2048
Silicon Vendor
STMicroelectronics
Pin count
176
RAM (Bytes)
393216
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Fusion for STM32 v8 as your development board.
Track your results in real time
Application Output via UART Mode
1. Once the code example is loaded, pressing the "FLASH" button initiates the build process, and programs it on the created setup.
2. After the programming is completed, click on the Tools icon in the upper-right panel, and select the UART Terminal.
3. After opening the UART Terminal tab, first check the baud rate setting in the Options menu (default is 115200). If this parameter is correct, activate the terminal by clicking the "CONNECT" button.
4. Now terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.
Software Support
Library Description
This library contains API for EEPROM 3 Click driver.
Key functions:
eeprom3_write_byte- This function writes data to the desired registereeprom3_write_page- This function writes given number of data to the desired registereeprom3_read- This function reads data from the desired register.
Open Source
Code example
This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.
/*!
* \file
* \brief Eeprom3 Click example
*
* # Description
* This application demonstrates the process of reading and writing to the EEPROM.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes EEPROM 3 driver.
*
* ## Application Task
* Writing data to EEPROM, reading that data and displaying it via UART
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "eeprom3.h"
// ------------------------------------------------------------------ VARIABLES
static eeprom3_t eeprom3;
static log_t logger;
uint8_t text[ 7 ] = { 'M','i','k','r','o','e' };
uint8_t mem_value[ 7 ] = { 0 };
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
eeprom3_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.
eeprom3_cfg_setup( &cfg );
EEPROM3_MAP_MIKROBUS( cfg, MIKROBUS_1 );
eeprom3_init( &eeprom3, &cfg );
}
void application_task ( void )
{
eeprom3_write_page( &eeprom3, 0x100, text, 6 );
log_printf( &logger, "Writing Mikroe to EEPROM 3 click\r\n" );
Delay_ms ( 1000 );
eeprom3_read( &eeprom3, 0x100, mem_value, 6 );
log_printf( &logger, "Data read: %s\r\n", mem_value );
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
