TM4C129ENCPDT: How to programmatically save permanent MAC in NV RAM ?

Serge Skorodinsky

Part Number: TM4C129ENCPDT

Tool/software:

I have working ethernet application where I have checked on power up if MAC is not in NV RAM so I substitute temporal MAC.

But I would like to save in NV RAM permanent MAC which I am getting from uart.
I know I can use LM Flash programmer, it works, but I do not want to use it, I would really like to save MAC by my own code.
I saw this link, mentioned EMACAddrSet() to do so, but it is not really working, and according to documentation, this function is not to save MAC into NV RAM, but rather to set MAC (either permanent or not) for Ethernet interface. Cannot find example of how to really save MAC in NV RAM.

Does anybody have such example?

over 1 year ago

0 Charles Tsai over 1 year ago

TI__Guru**** 191296 points

Hi,

You are repeating the same question that I have been assisting in https://e2e.ti.com/support/microcontrollers/arm-based-microcontrollers-group/arm-based-microcontrollers/f/arm-based-microcontrollers-forum/1380013/tm4c129encpdt-how-to-change-mac-not-saved-yet-in-nv-registers-on-the-fly. If you want to use the new thread here, it is fine then I will not go back to that post. Please read my latest response and you can answer here.

0 Serge Skorodinsky over 1 year ago in reply to Charles Tsai

Intellectual 370 points

It is not the same questions... Here I am asking how to really save permanent MAC in NV ram, over there I am asking on how to substitute another temporal (not saved in NV Ram) MAC and start use it without restart micro...

0 Charles Tsai over 1 year ago in reply to Serge Skorodinsky

TI__Guru**** 191296 points

ok. The easy way is to use LM flash programmer to save MAC into USER0/USER1 registers. See below example. Note that once the MAC is programmed, the only way to erase it is to go through a 'Unlock' operation which will perform a mass-erase of the device.

0 Serge Skorodinsky over 1 year ago in reply to Charles Tsai

Intellectual 370 points

I know how to use LM Flash programmer to save MAC, I have mentioned that... My question was how to save MAC into such registers with my code, not with LM Flash programmer.

0 Charles Tsai over 1 year ago in reply to Serge Skorodinsky

TI__Guru**** 191296 points

Hi,

Yes, you can program the MAC address from within the code. Please find this post for details.

https://e2e.ti.com/support/microcontrollers/arm-based-microcontrollers-group/arm-based-microcontrollers/f/arm-based-microcontrollers-forum/421196/tm4c-mac-address-programming-procedure?tisearch=e2e-sitesearch&keymatch=user_reg0#

0 Serge Skorodinsky over 1 year ago in reply to Charles Tsai

Intellectual 370 points

Thank you, but this post seem like to be more helpfull: https://e2e.ti.com/support/microcontrollers/arm-based-microcontrollers-group/arm-based-microcontrollers/f/arm-based-microcontrollers-forum/363569/how-to-manually-write-user0-and-user1-register-for-mac-address-without-lm-flash-programmer

Seems like it works for me, I have used these two functions:

int32_t ROM_FlashUserSet(uint32_t ui32User0, uint32_t ui32User1) ;
int32_t ROM_FlashUserSave(void)

Of course, it requires some extra logic because of you cannot easily reprogram MAC after that, so it should be kind of "one time logic".
Anyway, thank you for guiding me in proper direction.

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TM4C129ENCPDT: How to programmatically save permanent MAC in NV RAM ?