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MSP430F2274: is there an LOV

Forrest Fleming
Prodigy 20 points
Part Number: MSP430F2274

Tool/software:

Hello,

Im working on some documentation of our design for security and was wondering if i could get a Letter of Volatility for the MSP430F2274MRHATEP

  • +1
    TI__Guru 63361 points

    Hi Forrest,

    I'm being told we do not have a formal document discussing the volatility of the memory elements in the MSP430F2274 design.

    However, I can provide general information that covers this.

    The memory is organized as Main Flash: (64 x 512 byte) 32KB

    Information Flash: (4 x 64bit) 256 byte

    RAM: 1KB byte.

    Peripheral RAM: 512 byte.

    From the above list, the items labeled Flash are non-volatile, and will retain their contents through a power cycle.

    Customer code/data can live in the Main Flash, and also in parts of the information flash.

    To clear any contents from the FLASH, it is required to erase the FLASH. 

    Parts of the information flash, will contain device specific data used for calibration and features.  If this is erased, then the calibration data is no longer usable. 

    Additionally, there are registers within the design implemented with flip flops or registers.   These registers will be cleared with a power cycle.

    The RAM block and peripheral memory will be cleared with a power cycle.

    The only memory that will be retained from a power cycle are the elements labeled Flash.

    Hopefully this provides enough information.

    If not, you might try contacting your local TI Sales Representative or FAE.

  • 0 in reply to Dennis Lehman
    Prodigy 20 points

    First, Thank you so much for that information.

    would you be able to explain the size of those flip flops or/and registers?

     can you explain the uses for all those memories? you touched on the Main Flash and a part of the Information flashes Job.

    Lastly you talk about erasing the flash. Is there a document detailing how to do that?

  • 0 in reply to Forrest Fleming
    Guru 38390 points

    Note that if you erase the flash, your program will be gone.

    In my experience, a programmed microcontroller cannot be made secure and must be handled as classified property.

  • 0 in reply to Keith Barkley
    Prodigy 20 points

    honestly I'm fine if its gone after an erase. I'm just doing my diligence to see if I can clear it. and if I cant that's probably fine but I just need it in writing

  • 0 in reply to Forrest Fleming
    Guru 38390 points

    Well, then sure you can erase it.

  • +1 in reply to Keith Barkley
    TI__Guru 63361 points

    Hi Forrest,

    Forrest Fleming said:
    would you be able to explain the size of those flip flops or/and registers?

    Flip-flops are fundamental storage components in the design logic and can whose size can be one bit. They can change from 0->1 or 1->0, depending on the code that is executed by the CPU.  A flip-flop is volatile, which means its value can be changed by the CPU or cleared to 0 after a power-on reset.

    Registers are essentially a group of flip-flops and can vary in size.  The CPU has a set of working registers that are typically 16-bit.  Most peripherals use 16-bit registers, but some may only be 8-bit.  These too are volatile, so their value is changed by the CPU or device reset.

    Forrest Fleming said:
    can you explain the uses for all those memories?

    RAM is basically a large collection of registers mapped together and used by the CPU to temporarily store data.  It too is volatile so after a power-on reset, the RAM is cleared to all zeros.

    As Keith mentioned, FLASH is a type of memory that is programmed with the CPU instructions (code a.k.a firmware).  It is non-volatile which means the contents cannot change if the device is reset or goes through a power cycle.  FLASH memory can be changed with three methods.

    1. External programmer/debugger connected to the device's programming pins uses the internal FLASH controller peripheral to erase and write the code into memory

    2. BSL - the device's boot strap loader (which typically resides in ROM - read only memory) communicates with another MCU, using UART or I2C communications interface.  The device (host) device or MCU sends commands to the MSP where the CPU will execute specific instructions to erase and program FLASH memories.

    3. Application - the CPU has the ability to execute the erase and programming functions the same as an external programmer as part of the application code.

    INFO memory is also FLASH and is dedicated to hold data rather than CPU instructions.  INFO memory is typically used to store data that must retain its value when the device is reset or power cycled.

    Forrest Fleming said:
    Lastly you talk about erasing the flash. Is there a document detailing how to do that?

    Erasing the FLASH can be done via the three methods described above and is done right before new FLASH code is programmed into the device.  The device's datasheet has a section covering the erasure and FLASH programming using the FLASH controller peripheral.

    Does this help?

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