MSP430FR2311: MSP430 FRAM write/ read

Walter Macamos

Genius 5345 points

Part Number: MSP430FR2311

Hi TI Team,

The MSP430FR2311PW20 got the FRAM, right?

Looking for any sample code to read/write from/to FRAM .

Regards,

Walter

over 6 years ago

0 Yiding Luo over 6 years ago

TI__Expert 5490 points

Hello Walter,

Here are some example projects for FR2311 device and there are couple for FRAM write.

http://dev.ti.com/tirex/explore/node?node=ANl1oYi0.klyjvtEKGoMlA__IOGqZri__LATEST&search=MSP430FR2311

Thanks,

Yiding

0 Walter Macamos over 6 years ago in reply to Yiding Luo

Genius 5345 points

Thanks Yiding,

What is the FRAM memory for information data purpose only? Or, no difference?

The memory map of the MSP430FR231x MCUs only shows the range:

FFFFh to FF80h

FFFFh to F100h

Regards,

Walter

0 Walter Macamos over 6 years ago in reply to Walter Macamos

Genius 5345 points

Hi Yiding,

Writing is set during run time and can read the value.

After reboot, I read value but the value not retained

#define FRAM_TEST_START 0xFD00

unsigned int *pointer;

unsigned int data;

void main()

{

pointer = (unsigned int *)FRAM_TEST_START; // address to read

data = *pointer; // data to read

while(1);

}

0 Walter Macamos over 6 years ago in reply to Walter Macamos

Genius 5345 points

Hi TI Team,

Planning to use persistent, but still cannot read after boot:

http://dev.ti.com/tirex/explore/node?node=ALjQeIC7Hu5Y4ISuzhBZQw__IOGqZri__LATEST&search=MSP430FR2311

Regards,

Walter

0 Yiding Luo over 6 years ago in reply to Walter Macamos

TI__Expert 5490 points

Hello Walter,

Can you provide more information on what you mean by cannot read after boot?

Thanks,

Yiding

0 Walter Macamos over 6 years ago in reply to Yiding Luo

Genius 5345 points

Hi Yiding,

I was just using simple persistent variable.

-------------------------------------------------

#pragma PERSISTENT(value)

unsigned long value = 0;

WDTCTL = WDTPW | WDTHOLD; // Stop WDT

SYSCFG0 = FRWPPW; // Program FRAM write enable

value++;

SYSCFG0 = FRWPPW | PFWP; // Program FRAM write protecte

-----------------------------

Do I need to add this?

RTCCTL = 0;

PMMCTL0_H = PMMPW_H; // Open PMM Registers for write
PMMCTL0_L |= PMMREGOFF; // and set PMMREGOFF
PMMCTL0_H = 0; // Lock PMM Registers

I was expecting to be able to read the value saved after power cycle.

if(value)

{

// correcly writetn.

}

else{

// not correcly writetn.

}

Regards,

Walter

0 Walter Macamos over 6 years ago in reply to Walter Macamos

Genius 5345 points

By definition, it should work like this.

1 2	`#pragma PERSISTENT ( count )` `uint16_t count = 0;`

creates the variable "count" and tells the code generation tools to place it in "persistent" memory; that is, the variable will be placed in FRAM, which is a persistent type of memory. Handled this way, your code can read and write the variable just like it's located in RAM, but its value will be retained even if power is removed from the device.

0 Yiding Luo over 5 years ago in reply to Walter Macamos

TI__Expert 5490 points

Hello Walter,

You are correct that by setting the variable PERSISTENT it will be placed into FRAM, you can find this in lnk_msp430fr2311.cmd file which shows:

GROUP(READ_WRITE_MEMORY)
{
.TI.persistent : {} /* For #pragma persistent */
}

>FRAM

To write to FRAM you need to enable FRAM write which you are doing it by

SYSCFG0 = FRWPPW; // Program FRAM write enable

value++;

SYSCFG0 = FRWPPW | PFWP; // Program FRAM write protecte

So I would like to first check if the program correctly placed the variable into FRAM. Can you use debugger to check the PERSISTENT variable address? This variable should be placed in FRAM memory address range. FRAM: origin = 0xF100, length = 0xE80

Thanks,

Yiding

0 Walter Macamos over 5 years ago in reply to Yiding Luo

Genius 5345 points

Data is there but when I reboot system, then read immediately after boot. Data id back to zero.

0 Yiding Luo over 5 years ago in reply to Walter Macamos

TI__Expert 5490 points

Hello Walter,

How did you read the value after reset the power? If you use the debugger standard setting it will reset the value after you debug the device.

I just tried on a FR2311 Launchpad and here is the simple code to test PERSISTENT variable.

If the LED is on after boot that means the variable Port_event retained its value after reset the power.

#include <msp430.h>

// Statically-initialized variable
#ifdef __TI_COMPILER_VERSION__
#pragma PERSISTENT(Port_event)
unsigned long Port_event = 0;
#endif

void initGpio(void);

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

    // Configure GPIO
    initGpio();

    if(Port_event == 6)
    {
        P1OUT |= BIT0;
    }
    else
    {
        P1OUT &= ~BIT0;
    }

    while(Port_event <= 5)
    {
    SYSCFG0 = FRWPPW;                   // Program FRAM write enable
    Port_event++;                       // Record the port event in FRAM
    SYSCFG0 = FRWPPW | PFWP;            // Program FRAM write protected (not writable)
    }

    while(1)
    {
        __no_operation();
    }

}

void initGpio()
{
    P1DIR = 0xFF; P2DIR = 0xFF;
    P1REN = 0xFF; P2REN = 0xFF;
    P1OUT = 0x00; P2OUT = 0x00;

    // Disable the GPIO power-on default high-impedance mode
    // to activate previously configured port settings
    PM5CTL0 &= ~LOCKLPM5;
}

Thanks,

Yiding

0 Walter Macamos over 5 years ago in reply to Yiding Luo

Genius 5345 points

Hi Yiding,

ok, Do we need to stop watchdog?

Regards,

Walter

0 Yiding Luo over 5 years ago in reply to Walter Macamos

TI__Expert 5490 points

Hello Walter,

For your program if you don't want to use watchdog then it should be disabled.

However, even if you enabled the watchdog timer and there is a watchdog timer reset it should not reset PERSISTENT variables.

Thanks,

Yiding

0 Walter Macamos over 5 years ago in reply to Yiding Luo

Genius 5345 points

Hi Yiding,

Now OK.

Regards,

Walter

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MSP430FR2311: MSP430 FRAM write/ read