Intermediate
30 min

Make safe data storage with CAV24C512 and STM32F446ZE

Efficient nonvolatile data storage

EEPROM 8 Click with UNI-DS v8

Published Apr 03, 2023

Click board™

EEPROM 8 Click

Dev Board

UNI-DS v8

Compiler

NECTO Studio

MCU

STM32F446ZE

Keep your data safe and secure in silicon for a century

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Hardware Overview

How does it work?

EEPROM 8 Click is based on the CAV24C512, a 512-Kb EEPROM with an I2C interface and Write Protection Mode from ON Semiconductor. The CAV24C512 is organized as 65,536 words of 8 bits each and benefits from a wide power supply range and 100 years of data retention combining their unprecedented data storage with excellent energy efficiency. It is highly reliable, lasting one million full-memory read/write/erase cycles. On-chip Error Correction Code (ECC) makes this Click board™ suitable for high-reliability applications where dependable nonvolatile memory storage is essential.

This Click board™ communicates with MCU using the standard I2C 2-Wire interface that supports Standard (100 kHz), Fast (400 kHz), and Fast-Plus (1MHz) modes of operation. The CAV24C512 has a 7-bit slave address with the first five MSBs fixed to 1010. The address pins A0, A1, and A2 are programmed by the user and determine the value of the last three LSBs of the slave address, which can be selected by positioning onboard SMD jumpers labeled as ADDR SEL to an appropriate position marked as 0 or 1. Also, the configurable Write Protection function, the WP pin of the mikroBUS™

socket, allows the user to freeze the entire memory area, thus protecting it from Write instructions. 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. However, the 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.

EEPROM 8 Click top side image
EEPROM 8 Click lateral side image
EEPROM 8 Click bottom side image

Features overview

Development board

UNI-DS 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 STM32, Kinetis, TIVA, CEC, MSP, PIC, dsPIC, PIC32, and AVR MCUs 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, UNI-DS v8 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the UNI-DS 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. UNI-DS 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.

UNI-DS v8 horizontal image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

ARM Cortex-M4

MCU Memory (KB)

512

Silicon Vendor

STMicroelectronics

Pin count

144

RAM (Bytes)

131072

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
NC
NC
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
Write Protect
PD12
PWM
NC
NC
INT
NC
NC
TX
NC
NC
RX
I2C Clock
PB8
SCL
I2C Data
PB9
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Schematic

EEPROM 8 Click Schematic schematic

Step by step

Project assembly

Fusion for PIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI-DS v8 as your development board.

Fusion for PIC v8 front image hardware assembly
Buck 22 Click front image hardware assembly
SiBRAIN for PIC32MZ1024EFK144 front image hardware assembly
v8 SiBRAIN MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

Track your results in real time

Application Output

After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.

UART Application Output Step 1

Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.

UART Application Output Step 2

In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".

UART Application Output Step 3

The next step is to click on the "CONNECT" button, after which the terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.

UART Application Output Step 4

Software Support

Library Description

This library contains API for EEPROM 8 Click driver.

Key functions:

  • eeprom8_write_page This function writes up to 128 bytes of data starting from the selected register.

  • eeprom8_read_random_byte This function reads one byte data from the desired register.

  • eeprom8_read_sequential This function reads the desired number of bytes starting from the selected 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 main.c
 * @brief EEPROM8 Click example
 *
 * # Description
 * This example demonstrates the use of EEPROM 8 click board by writing specified data to
 * the memory and reading it back.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and USB UART logging.
 *
 * ## Application Task
 * Task writes a desired number of data bytes to the EEPROM 8 memory 
 * and verifies that it is written correctly by reading from the same memory location and 
 * in case of successful read, displays the memory content on the USB UART. 
 * This is done in two passes.
 *
 * @author Stefan Popovic
 *
 */

#include "board.h"
#include "log.h"
#include "eeprom8.h"

static eeprom8_t eeprom8;
static log_t logger;

// Number of test bytes
#define TEST_NBYTES ( 150 )

// Starting address for example
#define TEST_MEM_LOCATION ( EEPROM8_BLOCK_ADDR_START + 1024ul )

static uint8_t  cnt = 0;
static uint8_t  test_write_buffer[ TEST_NBYTES ]  = { 0 };
static uint8_t  test_read_buffer[ TEST_NBYTES ]   = { 0 };
static uint16_t addr_offset = TEST_MEM_LOCATION;

/**
 * @brief First pass function
 * @details This function writes and reads defined number of bytes
 *  with zero values
 * @param[in] ctx  Click object.
 * @param[in] write_buf  Data to be written.
 * @param[out] read_buf  Data to be read.
 * @return @li @c  0 - Success,
 *         @li @c -1 - Error.
 * See #err_t definition for detailed explanation.
 * @note None.
 */
err_t run_first_pass( eeprom8_t* ctx, uint8_t* write_buf, uint8_t* read_buf );

/**
 * @brief Second pass function
 * @details This function writes and reads defined number of bytes
 *  with the values following arithmetical progression
 * @param[in] ctx  Click object.
 * @param[in] write_buf  Data to be written.
 * @param[out] read_buf  Data to be read.
 * @return @li @c  0 - Success,
 *         @li @c -1 - Error.
 * See #err_t definition for detailed explanation.
 * @note None.
 */
err_t run_second_pass( eeprom8_t* ctx, uint8_t* write_buf, uint8_t* read_buf );

void application_init ( void ) 
{
    eeprom8_cfg_t eeprom8_cfg;  /**< Click config object. */
    log_cfg_t log_cfg;          /**< Logger config object. */
    
    /** 
     * 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.
    eeprom8_cfg_setup( &eeprom8_cfg );
    EEPROM8_MAP_MIKROBUS( eeprom8_cfg, MIKROBUS_1 );
    if ( I2C_MASTER_ERROR == eeprom8_init( &eeprom8, &eeprom8_cfg ) )
    {
        log_error( &logger, " Communication Init " );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    // Reset variables
    cnt = 0;
    memset( test_read_buffer, 0, sizeof ( test_read_buffer ) );
    addr_offset = TEST_MEM_LOCATION;
    
    // Initiate first pass 
    //  filling the eeprom addresses with zeros 
    if( EEPROM8_ERROR == run_first_pass( &eeprom8, test_write_buffer, test_read_buffer ) )
    {
        log_error( &logger, " First Pass Failed " );
    }
    
    // Initiate second pass 
    //  filling the eeprom addresses with values following arithmetic sequence with difference of 1 
    if( EEPROM8_ERROR == run_second_pass( &eeprom8, test_write_buffer, test_read_buffer ) )
    {
        log_error( &logger, " Second Pass Failed " );
    }
    
    log_printf( &logger, " \r\nInitiating new iteration\r\n " );
    Delay_ms( 6000 );
}

void main ( void ) 
{
    application_init( );

    for ( ; ; ) 
    {
        application_task( );
    }
}

// First pass: writing zero values into eeprom memory and reading them back
err_t run_first_pass( eeprom8_t* ctx, uint8_t* write_buf, uint8_t* read_buf )
{
    // Fill write buffer with zeros
    memset( write_buf, 0, TEST_NBYTES );
    
    // Fill whole page with zeros using page write operation
    eeprom8_write_enable( ctx );
    if ( EEPROM8_ERROR == eeprom8_write_page( ctx, addr_offset, write_buf ) )
    {
        log_error( &logger, " Write Page Failed " );
        return EEPROM8_ERROR;
    }
    cnt += EEPROM8_NBYTES_PAGE;
    
    // Fill remaining adresses with zero using byte write operation
    addr_offset += EEPROM8_NBYTES_PAGE;

    while( cnt < TEST_NBYTES )
    {
        if ( EEPROM8_ERROR == eeprom8_write_byte( ctx, addr_offset++, 0 ) )
        {
            log_error( &logger, " Write %d. Byte Failed ", ( uint16_t ) cnt );
            return EEPROM8_ERROR;
        }
        cnt++;
        Delay_10ms( );
    }
    eeprom8_write_protect( ctx );

    Delay_1sec( );
    
    // Read defined number of bytes starting from the test memory location
    addr_offset = TEST_MEM_LOCATION;
    if ( EEPROM8_ERROR == eeprom8_read_sequential( ctx, addr_offset, TEST_NBYTES, read_buf ) )
    {
         log_error( &logger, "Read Sequential Failed" );
         return EEPROM8_ERROR;
    }
  
    // compare written and read buffers and log data in case of a match 
    if ( memcmp( write_buf, read_buf, sizeof( write_buf ) ) == 0 )
    {
        log_printf( &logger, 
                    " \r\nFirst pass: reading %d bytes data starting from eeprom address 0x%x\r\n ", 
                    ( uint16_t ) TEST_NBYTES, 
                    ( uint32_t ) TEST_MEM_LOCATION );
        for ( cnt = 0; cnt < TEST_NBYTES; cnt++ )
        {
            log_printf( &logger, " %d", ( uint16_t ) read_buf[ cnt ] );
            Delay_ms( 50 );
        }
    
        log_printf( &logger, "\r\n\r\n" );
    }
    else
    {
        return EEPROM8_ERROR;
    }
    return EEPROM8_OK;
}

// Second pass: writing incremental values into eeprom memory and reading them back
err_t run_second_pass( eeprom8_t* ctx, uint8_t* write_buf, uint8_t* read_buf )
{
    for ( cnt = 0; cnt < TEST_NBYTES; cnt++ )
    {
        write_buf[ cnt ] = cnt + 1;
    }
    // Write buffer data using page write operation
    cnt = 0;
    eeprom8_write_enable( ctx );
    if ( EEPROM8_ERROR == eeprom8_write_page( ctx, addr_offset, write_buf ) )
    {
        log_error( &logger, " Write Page Failed ");
        return EEPROM8_ERROR;
    }
    cnt += EEPROM8_NBYTES_PAGE;
    
    // Write remaining buffer data using byte write operation
    addr_offset += EEPROM8_NBYTES_PAGE;

    while ( cnt < TEST_NBYTES )
    {
        if ( EEPROM8_ERROR == eeprom8_write_byte( ctx, addr_offset++, write_buf[ cnt++ ] ) )
        {
            log_error( &logger, " Write %d. Byte Failed ", ( uint16_t ) cnt );
            return EEPROM8_ERROR;
        }
        Delay_10ms( );
    }
    eeprom8_write_protect( ctx );

    Delay_ms( 1000 );
    
    // Read bytes of the page size starting from the test memory location
    addr_offset = TEST_MEM_LOCATION;
    if ( EEPROM8_ERROR == eeprom8_read_sequential( ctx, addr_offset, EEPROM8_NBYTES_PAGE, read_buf ) )
    {
        log_error( &logger, " Read Sequential Failed " );
        return EEPROM8_ERROR;
    }
    
    // Read two bytes with random byte read operation
    addr_offset += EEPROM8_NBYTES_PAGE;
    cnt = EEPROM8_NBYTES_PAGE;

    if( EEPROM8_ERROR == eeprom8_read_random_byte( ctx, addr_offset, &read_buf[ cnt++ ] ) )
    {
        log_error( &logger, " Read %d. Random Byte Failed ", ( uint16_t ) cnt-1 );
        return EEPROM8_ERROR;
    }
    ++addr_offset;
    if( EEPROM8_ERROR == eeprom8_read_random_byte( ctx, addr_offset, &read_buf[ cnt++ ] ) )
    {
        log_error( &logger, " Read %d. Random Byte Failed ", ( uint16_t ) cnt-1 );
        return EEPROM8_ERROR;
    }
    
    // Read the rest of the bytes with current address read operation
    while ( cnt < TEST_NBYTES )
    {
        if( EEPROM8_ERROR == eeprom8_read_current_byte( ctx, &read_buf[ cnt++ ] ) )
        {
            log_error( &logger, " Read %d. Current Byte Failed ", ( uint16_t ) cnt-1 );
            return EEPROM8_ERROR;
        }
    }
    // compare written and read buffers and log data in case of a match
    if ( memcmp( write_buf, read_buf, TEST_NBYTES ) == 0 )
    {
        log_printf( &logger, 
                    " \r\nSecond pass: reading %d bytes data starting from eeprom address 0x%x\r\n ", 
                    ( uint16_t ) TEST_NBYTES, 
                    ( uint32_t ) TEST_MEM_LOCATION );
        for ( cnt = 0; cnt < TEST_NBYTES; cnt++ )
        {
            log_printf( &logger, " %d", ( uint16_t )read_buf[ cnt ] );
            Delay_ms( 50 );
        }
    
        log_printf( &logger, "\r\n\r\n" );
    }
    else
    {
        return EEPROM8_ERROR;
    }
    return EEPROM8_OK;
}

// ------------------------------------------------------------------------ END

Additional Support

Resources