SLAA649G October   2014  – August 2021 MSP430F2001 , MSP430F2002 , MSP430F2003 , MSP430F2011 , MSP430F2012 , MSP430F2013 , MSP430F2013-EP , MSP430F2101 , MSP430F2111 , MSP430F2112 , MSP430F2121 , MSP430F2122 , MSP430F2131 , MSP430F2132 , MSP430F2232 , MSP430F2234 , MSP430F2252 , MSP430F2254 , MSP430F2272 , MSP430F2274 , MSP430F2274-EP , MSP430F233 , MSP430F2330 , MSP430F235 , MSP430F2350 , MSP430F2370 , MSP430F2410 , MSP430F2416 , MSP430F2417 , MSP430F2418 , MSP430F2419 , MSP430F247 , MSP430F2471 , MSP430F248 , MSP430F2481 , MSP430F249 , MSP430F249-EP , MSP430F2491 , MSP430F2616 , MSP430F2617 , MSP430F2618 , MSP430F2619 , MSP430F2619S-HT , MSP430FR2032 , MSP430FR2033 , MSP430FR2110 , MSP430FR2111 , MSP430FR2153 , MSP430FR2155 , MSP430FR2310 , MSP430FR2311 , MSP430FR2353 , MSP430FR2355 , MSP430FR2433 , MSP430FR2475 , MSP430FR2476 , MSP430FR2532 , MSP430FR2533 , MSP430FR2632 , MSP430FR2633 , MSP430FR2672 , MSP430FR2673 , MSP430FR2675 , MSP430FR2676 , MSP430FR4131 , MSP430FR4132 , MSP430FR4133 , MSP430G2001 , MSP430G2101 , MSP430G2102 , MSP430G2111 , MSP430G2112 , MSP430G2121 , MSP430G2131 , MSP430G2132 , MSP430G2152 , MSP430G2153 , MSP430G2201 , MSP430G2202 , MSP430G2203 , MSP430G2210 , MSP430G2211 , MSP430G2212 , MSP430G2213 , MSP430G2221 , MSP430G2230 , MSP430G2230-EP , MSP430G2231 , MSP430G2231-EP , MSP430G2232 , MSP430G2233 , MSP430G2252 , MSP430G2253 , MSP430G2302 , MSP430G2302-EP , MSP430G2303 , MSP430G2312 , MSP430G2313 , MSP430G2332 , MSP430G2332-EP , MSP430G2333 , MSP430G2352 , MSP430G2353 , MSP430G2402 , MSP430G2403 , MSP430G2412 , MSP430G2413 , MSP430G2432 , MSP430G2433 , MSP430G2444 , MSP430G2452 , MSP430G2453 , MSP430G2513 , MSP430G2533 , MSP430G2544 , MSP430G2553 , MSP430G2744 , MSP430G2755 , MSP430G2855 , MSP430G2955 , MSP430I2020 , MSP430I2021 , MSP430I2030 , MSP430I2031 , MSP430I2040 , MSP430I2041

 

  1.   Trademarks
  2. 1 Introduction
  3. 2 Comparison of MSP430FR4xx and MSP430FR2xx Devices
  4. 3 In-System Programming of Nonvolatile Memory
    1. 3.1 Ferroelectric RAM (FRAM) Overview
    2. 3.2 FRAM Cell
    3. 3.3 Protecting FRAM Using the Memory Write Protection Bit
    4. 3.4 FRAM Memory Wait States
    5. 3.5 Bootloader (BSL)
    6. 3.6 JTAG and Security
    7. 3.7 Production Programming
  5. 4 Hardware Migration Considerations
  6. 5 Device Calibration Information
  7. 6 Important Device Specifications
  8. 7 Core Architecture Considerations
    1. 7.1 Power Management Module (PMM)
      1. 7.1.1 Core LDO and LPM3.5 LDO
      2. 7.1.2 SVS
      3. 7.1.3 VREF
      4. 7.1.4 Debug in Low-Power Mode
    2. 7.2 Clock System
      1. 7.2.1 DCO Frequencies
      2. 7.2.2 FLL, REFO, and DCO Tap
      3. 7.2.3 FRAM Access at 16 MHz, ADC Clock, and Clocks-on-Demand
    3. 7.3 Operating Modes, Wake-up Times, and Reset
      1. 7.3.1 LPMx.5
      2. 7.3.2 Reset
        1. 7.3.2.1 Behavior of POR and BOR
        2. 7.3.2.2 Reset Generation
        3. 7.3.2.3 Determining the Cause of Reset
    4. 7.4 Interrupt Vectors
    5. 7.5 FRAM and the FRAM Controller
      1. 7.5.1 Flash and FRAM Overview Comparison
      2. 7.5.2 Cache Architecture
  9. 8 Peripheral Considerations
    1. 8.1  Watchdog Timer
    2. 8.2  Ports
      1. 8.2.1 Digital Input/Output
      2. 8.2.2 Capacitive Touch I/O
    3. 8.3  Analog-to-Digital Converters
      1. 8.3.1 ADC10 to ADC
    4. 8.4  Communication Modules
      1. 8.4.1 USI to eUSCI
      2. 8.4.2 USCI to eUSCI
    5. 8.5  Timer and IR Modulation Logic
    6. 8.6  Backup Memory
    7. 8.7  Hardware Multiplier (MPY32)
    8. 8.8  RTC Counter
    9. 8.9  Interrupt Compare Controller (ICC)
    10. 8.10 LCD
    11. 8.11 Smart Analog Combo (SAC)
    12. 8.12 Comparator
  10. 9 ROM Libraries
  11. 10Conclusion
  12. 11References
  13. 12Revision History

3.3 Protecting FRAM Using the Memory Write Protection Bit

Because FRAM is very easy to reprogram, it also makes it easy for erroneous code execution to unintentionally overwrite application code, just as it would if executing from RAM.

To safeguard against erroneous overwriting of FRAM, memory write protection is provided. FR4xx provides two separate write protection bits:

  • SYSCFG0.PFWP – User program FRAM protection
  • SYSCFG0.DFWP – User data FRAM (information memory 1800h to 19FFh) protection

When writing the SYSCFG0 register, write the protection password (SYSCFG0.FRWPW = 0xA5) in a word with the other bits.

Table 3-1 summarizes the FRAM protection features in the typical devices of MSP430FR4xx and MSP430FR2xx family.

Table 3-1 FRAM Protection Features
FeatureFR2033FR4133FR2433FR2311FR2111FR2355FR2476
Protection password
(SYSCFG0.FRWPPW)		NNYYYYY
The program FRAM write protection
(SYSCFG0.PFWP)		YYYYYYY
The data FRAM protection
(SYSCFG0.DFWP)		YYYNNYY
Program FRAM write protection offset address (SYSCFG0.FRWPOA)NNNNNYY

When a write protection bit is set, any write to the protected FRAM is blocked but does not generate an interrupt or reset.

Note:

FRAM write protection should be enabled at all times except when a write operation is required. TI recommends completing the write operation within a short time with interrupts disabled to reduce the risk of unintended write operations. After the write operation completes, TI highly recommends enabling the FRAM write protection again as soon as possible to reduce the risk of unintended writes.

When writing data to FRAM, TI recommends using the __persistent attribute to define variables in FRAM memory. Code examples on how to write the FRAM are provided in the "Tools & software" tab of each FR4xx product folder (for example, MSP430FR4133 or MSP430FR2433). For more information about using FRAM technology in MSP430 MCUs from the software development perspective, see MSP430 FRAM technology – how to and best practices.