Forums

Re: lpc2xxx serial number

Started by andr...@gmail.com August 24, 2009
Hi all,

I am looking for the same thing now. When we connect with our jlink we get a unique serial number back so it IS present somewhere. Unfortunately NXP remains silent to our question how to read it out with software.

Regards,
Dreeke

Dear all,
> I would like to know if the lpc2xxx owns a serial number that uniquely identifies the device itself from any other device worldwide (I don't mean the part number, that identifies the device class, such as LPC2138 or LPC2366...).
> I need to use this serial number as a sort of "device address".
> If the serial number exists, where can I find it?
> Is it allocated somewhere in the on-chip memory? Is it readable?
>
> Otherwise, are you able to suggest me an alternative way to build a "device address"?
>
> Thanks in advance.
> Regards.
>
>---------------------------------
>Inviato da Yahoo! Mail.
>La casella di posta intelligente.
>
>
>

An Engineer's Guide to the LPC2100 Series

Hi,

> I am looking for the same thing now. When we connect with our jlink we get
> a unique serial number back so it IS present somewhere. Unfortunately NXP
> remains silent to our question how to read it out with software.

What format is the serial number you receive?

I seriously doubt here is a per-device unique serial number on any LPC2k.

--
Paul Curtis, Rowley Associates Ltd http://www.rowley.co.uk
CrossWorks V2 is out for LPC1700, LPC3100, LPC3200, SAM9, and more!
Hi Francesco,

> When we connect with our jlink we get
> a unique serial number back so it IS present somewhere. Unfortunately NXP
> remains silent to our question how to read it out with software.

If you mean numbers like these:

LPC2106 0xFFF0FF32 (4293984050 dec)
LPC2132 0x0002FF11 (196369 dec)
LPC2142 0x0402FF11 (67305233 dec)
LPC2148 0x0402FF25 (67305253 dec)

- they are merely device IDs that programming tools use to identify the *type* of the chip they are dealing with. They are not serial numbers.

For serial numbers you can use, as other on the forum have suggested, I2C serial number devices from Maxim DS2401 1-wire 64-bit serial ROM, or Maxim DS28CN01 I2C secure memory with 64-bit serial number.

You could as a matter of fact, also include the cheaper standard smallest size SPI serial EEPROMs and program them only once through a special header and connect only 'MOSI' line to the controller, to avoid accidental overwrite.

Embedding a serial number within the firmware image is also an option, but firmware upgrades are difficult, especially when the chip can be erased and reprogrammed entirely.

With a tiny external serial memory keeping the serial number safe, you can uniquely identify your boards, though not the processor. Plus, with some additional memory available you can even store some more information like manufacturing date, batch number, revision numbers, checksums etc to go with the serial number, that could be used both for detecting any tampering with this memory or to track the board's origins.
--- In l..., "Paul Curtis" wrote:
>
> Hi,
>
> > I am looking for the same thing now. When we connect with our jlink we get
> > a unique serial number back so it IS present somewhere. Unfortunately NXP
> > remains silent to our question how to read it out with software.
>
> What format is the serial number you receive?
>
> I seriously doubt here is a per-device unique serial number on any LPC2k.
>
> --
> Paul Curtis, Rowley Associates Ltd http://www.rowley.co.uk
> CrossWorks V2 is out for LPC1700, LPC3100, LPC3200, SAM9, and more!
>