CCS/MSP430FR2433: How to write to and read from FRAM?

Hi Sarah,

There are basic FRAM write examples in our MSP430Ware software package.

You can download the examples at the link above, or get them from the resource explorer in Code Composer Studio v8 since you're using that (go to View->Resource Explorer).

Writing to FRAM is very easy on the MSP430FR2433 as the memory protection mechanisms are very basic.  The code example below (taken from MSP430Ware) shows how to write a block of data:

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//******************************************************************************
//   MSP430FR243x Demo - Long word writes to FRAM
//
//   Description: Use long word write to write to 512 byte blocks of FRAM.
//   Toggle LED after every 100 writes.
//   NOTE: Running this example for extended periods will impact the FRAM
//   endurance.
//   ACLK = REFO, MCLK = SMCLK = default DCODIV = ~1MHz
//
//   It is recommended to disable interrupt while code is writing to main FRAM,
//   because it is dangerous for running the interrupt services routine with 
//   PFWP disabled.
//   This code examples is using DFWP which wouldn't have dangerous. But it is 
//   recommended to disable interrupt if user is using PFWP.
//
//           MSP430FR2433
//         ---------------
//     /|\|               |
//      | |               |
//      --|RST            |
//        |               |
//        |          P1.0 |---> LED
//
//   Ling Zhu
//   Texas Instruments Inc.
//   Feb 2015
//   Built with IAR Embedded Workbench v6.20 & Code Composer Studio v6.0.1
//******************************************************************************
#include <msp430.h>

void FRAMWrite(void);

unsigned char count = 0;
unsigned long *FRAM_write_ptr;
unsigned long data;

#define FRAM_TEST_START 0x1800


int main(void)
{
    WDTCTL = WDTPW | WDTHOLD;               // Stop watchdog timer

    P1OUT &= ~BIT0;                         // Clear P1.0 output latch for a defined power-on state
    P1DIR |= BIT0;                          // Set P1.0 to output directionOUT

    PM5CTL0 &= ~LOCKLPM5;                   // Disable the GPIO power-on default high-impedance mode
                                            // to activate previously configured port settings
    data = 0x11111111;                      // Initialize dummy data

    while(1)
    {
        data += 0x00010001;
        FRAM_write_ptr = (unsigned long *)FRAM_TEST_START;
        FRAMWrite();
        count++;
        if (count > 100)
        {
            P1OUT ^= 0x01;                  // Toggle LED to show 512 bytes
            count = 0;                      // have been written
            data = 0x11111111;
        }
    }
}

void FRAMWrite (void)
{
    unsigned int i=0;

    SYSCFG0 = FRWPPW | PFWP;
    for (i = 0; i < 128; i++)
    {
        *FRAM_write_ptr++ = data;
    }
    SYSCFG0 = FRWPPW | PFWP | DFWP;
}

Let me know if you have further questions.

Regards,
Walter