MSP432E401Y: How to unlock the mac address ?

Finn Boger

Part Number: MSP432E401Y
Other Parts Discussed in Thread: SEGGER,

I have been running the code below several times and realized that it does not work anymore, the chip is locked. This is a custom board, can I unlock the chip from CCS and with a SEGGER J-Link Emulator or do I need to physically set the reset signal?

We are going to use these boards in systems where we may have from 1 - 10 units and would like to have control of the mac addresses. Somehow I have been able to set one board to mac address 0000.

if ((ulUser0 == 0xffffffff) && (ulUser1 == 0xffffffff))
{
/* Generate new random MAC and restart */
ulUser0 = rand()|(rand()<<16);
ulUser1 = rand()|(rand()<<16);
FlashUserSet(ulUser0, ulUser1);
FlashUserSave();
SysCtlReset();

/* If not present, return error. */
return false;
}

over 4 years ago

0 Bruce McKenney over 4 years ago

Guru 100385 points

Is the whole MCU stuck, or are you just not able to write USRREG0/1?

You can ask CCS to program USRREG0/1 using "[Debug Perspective]->Tools->On-Chip Flash". This is only available when the debugger is connected. (The similar-looking screen at "Project->Properties->Debug->MSP432E4 Flash Settings" does nothing knowable.)

[Edit: There may be something useful in this discussion. Skip to the end, though, it's mostly me scratching my head:

https://e2e.ti.com/support/microcontrollers/msp430/f/msp-low-power-microcontroller-forum/871656/ccs-msp432e401y-writing-mac-address-using-ccs/

0 Finn Boger over 4 years ago in reply to Bruce McKenney

Prodigy 230 points

Thanks, but I cannot find the On-Chip Flash, nor the MSP432E4 Flash Settings.

I am using ccs 10 and a SEGGER J-Link Emulator to run the MSP432E401Y. Cannot find any possibility to write to USRREG0/1 or unlocking the mac address.

0 Eason Zhou over 4 years ago in reply to Finn Boger

TI__Mastermind 39775 points

Hi Boger,

Hope it can help you.

Eason

0 Finn Boger over 4 years ago in reply to Eason Zhou

Prodigy 230 points

Thanks, but I am using a Jegger J-LINK Emulator and doesn't have access to this functionality.

+1 Bruce McKenney over 4 years ago in reply to Finn Boger

Guru 100385 points

I hadn't tried a J-Link with an MSP432E401Y. I think I succeeded in using Jlink.exe to do a Factory Reset, which (among other things) clears the USER_REG-s so you can put a new MAC there.

This is the sequence described in TRM (SLAU723A) Sec 4.1.6.6. Writing the HSSR (0x400fe1f4) is what does it. Don't type the stuff in [].

[Standard Disclaimer: This does a Mass Erase No Kidding.]

J-Link> connect MSP432E401Y
J-Link> mem32 0x400fe1d0 10  [The current MAC is the first two words of the second line]
J-Link> w4 0x20004000 feed0001 02010100 0d080503 59372215 [From TRM Sec 4.1.6.6]
J-Link> w4 0x400fe1f4 ca004000  [Write HSSR Ref TRM Sec 4.2.31. The 4000 is 0x20004000 in the previous line]
J-Link> mem32 0x400fe1d0 10  [The second line should be 0xFF-s now]

0 Finn Boger over 4 years ago in reply to Bruce McKenney

Prodigy 230 points

Thanks, that solved my problem. Have lost some hours on this one.

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MSP432E401Y: How to unlock the mac address ?