MRAM 4 Click

MRAM 4 Click is a compact add-on board representing a magneto-resistive random-access memory solution. This board features the EM064LX, an industrial STT-MRAM persistent memory from Everspin Technologies. It is a 64Mb MRAM IC RAM and can achieve up to 200MHz as a single and double data rate (STR/DTR). The MRAM technology is analog to Flash technology with SRAM-compatible read/write timings (Persistent SRAM, P-SRAM), where data is always non-volatile. It also has a hardware write-protection feature and performs read and write operations with data retention for ten years and unlimited read, write, and erase operations for the supported life of the chip.

Click Product page

Click library

• Author : Nenad Filipovic
• Date : Aug 2023.
• Type : SPI type

Software Support

We provide a library for the MRAM 4 Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for MRAM 4 Click driver.

Standard key functions :

• mram4_cfg_setup Config Object Initialization function.

  void mram4_cfg_setup ( mram4_cfg_t *cfg );

• mram4_init Initialization function.

  err_t mram4_init ( mram4_t *ctx, mram4_cfg_t *cfg );

• mram4_default_cfg Click Default Configuration function.

  err_t mram4_default_cfg ( mram4_t *ctx );

Example key functions :

• mram4_memory_write MRAM 4 memory write function.

  err_t mram4_memory_write ( mram4_t *ctx, uint32_t mem_addr, uint8_t *data_in, uint8_t len );

• mram4_memory_read MRAM 4 memory read function.

  err_t mram4_memory_read ( mram4_t *ctx, uint32_t mem_addr, uint8_t *data_out, uint8_t len );

• mram4_block_erase MRAM 4 block erase function.

  err_t mram4_block_erase ( mram4_t *ctx, uint8_t cmd_block_erase, uint32_t mem_addr );

Example Description

This example demonstrates the use of MRAM 4 Click board. The demo app writes specified data to the memory and reads it back.

The demo application is composed of two sections :

Application Init

The initialization of SPI module, log UART, and additional pins. After the driver init, the app executes a default configuration.

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    mram4_cfg_t mram4_cfg;  /**< Click 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.
    mram4_cfg_setup( &mram4_cfg );
    MRAM4_MAP_MIKROBUS( mram4_cfg, MIKROBUS_1 );
    if ( SPI_MASTER_ERROR == mram4_init( &mram4, &mram4_cfg ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    if ( MRAM4_ERROR == mram4_default_cfg ( &mram4 ) )
    {
        log_error( &logger, " Default configuration." );
        for ( ; ; );
    }
    Delay_ms ( 100 );

    log_info( &logger, " Application Task " );
    log_printf( &logger, "-----------------------\r\n" );
    Delay_ms ( 100 );
}

Application Task

The demo application writes a desired number of bytes to the memory and then verifies if it is written correctly by reading from the same memory location and displaying the memory content. Results are being sent to the UART Terminal, where you can track their changes.

void application_task ( void )
{
    uint8_t data_buf[ 128 ] = { 0 };
    log_printf( &logger, " Memory address: 0x%.6LX\r\n", ( uint32_t ) STARTING_ADDRESS );
    if ( MRAM4_OK == mram4_block_erase( &mram4, MRAM4_CMD_ERASE_4KB, STARTING_ADDRESS ) )
    {
        log_printf( &logger, " Erase memory block (4KB)\r\n" );
        Delay_ms ( 100 );
    }

    memcpy( data_buf, DEMO_TEXT_MESSAGE_1, strlen( DEMO_TEXT_MESSAGE_1 ) );    
    if ( MRAM4_OK == mram4_memory_write( &mram4, STARTING_ADDRESS, data_buf, sizeof( data_buf ) ) )
    {
        log_printf( &logger, " Write data: %s\r\n", data_buf );
        Delay_ms ( 100 );
    }

    memset( data_buf, 0, sizeof( data_buf ) );
    if ( MRAM4_OK == mram4_memory_read( &mram4, STARTING_ADDRESS, data_buf, sizeof( data_buf ) ) )
    {
        log_printf( &logger, " Read data: %s\r\n", data_buf );
        Delay_ms ( 1000 );
        Delay_ms ( 1000 );
        Delay_ms ( 1000 );
    }
    log_printf( &logger, " ----------------------------\r\n" );

    log_printf( &logger, " Memory address: 0x%.6LX\r\n", ( uint32_t ) STARTING_ADDRESS );
    if ( MRAM4_OK == mram4_block_erase( &mram4, MRAM4_CMD_ERASE_4KB, STARTING_ADDRESS ) )
    {
        log_printf( &logger, " Erase memory block (4KB)\r\n" );
    }

    memcpy( data_buf, DEMO_TEXT_MESSAGE_2, strlen( DEMO_TEXT_MESSAGE_2 ) );
    if ( MRAM4_OK == mram4_memory_write( &mram4, STARTING_ADDRESS, data_buf, sizeof( data_buf ) ) )
    {
        log_printf( &logger, " Write data: %s\r\n", data_buf );
        Delay_ms ( 100 );
    }

    memset( data_buf, 0, sizeof( data_buf ) );
    if ( MRAM4_OK == mram4_memory_read( &mram4, STARTING_ADDRESS, data_buf, sizeof( data_buf ) ) )
    {
        log_printf( &logger, " Read data: %s\r\n", data_buf );
        Delay_ms ( 1000 );
        Delay_ms ( 1000 );
        Delay_ms ( 1000 );
    }
    log_printf ( &logger, " ----------------------------\r\n" );
}

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.MRAM4

Additional notes and informations

Depending on the development board you are using, you may need USB UART Click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.