For a project I am working on, I would like to give boards fresh from
manufacturing a distinct "identity", before they are assigned a serial
number, or have a MAC address or IP address programmed, etc.
This could be provided by some devices, such as Maxim's DS2411
"Silicon serial number" ( with a "Unique, Factory-Lasered and Tested
64-Bit Registration Number" ) or DS18B20 temperature sensor, ( "has a
Unique 64-Bit Serial Code Stored in an On-Board ROM" )
Looking for the least expensive chip with such an ID, with an I2C
(preferred), SPI or 1-wire interface. Don't care what other
functionality that chip may have, I just want the unique ID.
A device that report its own serial number would be OK.
Any recommendations?
Thanks,
--
Roberto Waltman
[ Please reply to the group,
return address is invalid ]
On Fri, 10 Aug 2012 13:47:30 -0400, Roberto Waltman wrote:
> For a project I am working on, I would like to give boards fresh from
> manufacturing a distinct "identity", before they are assigned a serial
> number, or have a MAC address or IP address programmed, etc.
> This could be provided by some devices, such as Maxim's DS2411 "Silicon
> serial number" ( with a "Unique, Factory-Lasered and Tested 64-Bit
> Registration Number" ) or DS18B20 temperature sensor, ( "has a Unique
> 64-Bit Serial Code Stored in an On-Board ROM" )
> Looking for the least expensive chip with such an ID, with an I2C
> (preferred), SPI or 1-wire interface. Don't care what other
> functionality that chip may have, I just want the unique ID. A device
> that report its own serial number would be OK.
> Any recommendations?
> Thanks,
I use the Microchip 25AA02E48 in several products. It's SPI but the
24AA025E48 is I2C. They will run you about $0.23 in a SOT-23
package. Get them from Mouser,Digikey,Avnet or direct from Microchip.
Good news is you also get some EEPROM along with the MAC address.
> Joe Chisolm wrote:
>>> Looking for the least expensive chip with such an ID,
>> I use the Microchip 25AA02E48 in several products.
> Thanks, that's exactly what I need.
> --
> Roberto Waltman
Dallas did a good job with the one wire parts in general and only using one wire is a great thing. But they don't seem to be price competitive for who knows what reason. I seem to recall the one wire part that is the least expensive is one of their eeproms. I'm pretty sure it is lot more than a quarter. Heck, sometimes it is cheaper to emulate a one wire part with an MCU, but then you have to do your own serial number programming!
rickman <gnu...@gmail.com> wrote:
>On 8/10/2012 5:36 PM, Roberto Waltman wrote:
>> Joe Chisolm wrote:
>>>> Looking for the least expensive chip with such an ID,
>>> I use the Microchip 25AA02E48 in several products.
>> Thanks, that's exactly what I need.
>> --
>> Roberto Waltman
>Dallas did a good job with the one wire parts in general and only using >one wire is a great thing. But they don't seem to be price competitive >for who knows what reason. I seem to recall the one wire part that is >the least expensive is one of their eeproms. I'm pretty sure it is lot >more than a quarter. Heck, sometimes it is cheaper to emulate a one >wire part with an MCU, but then you have to do your own serial number >programming!
Nowadays a lot of MCUs come with a unique serial number.
-- Failure does not prove something is impossible, failure simply
indicates you are not using the right tools...
nico@nctdevpuntnl (punt=.)
--------------------------------------------------------------
> For a project I am working on, I would like to give boards fresh from
> manufacturing a distinct "identity", before they are assigned a serial
> number, or have a MAC address or IP address programmed, etc.
Does the board have a flash? Then maybe you already have a 64-bit unique ID available.
> On Fri, 10 Aug 2012 13:47:30 -0400, Roberto Waltman wrote:
> > For a project I am working on, I would like to give boards fresh from
> > manufacturing a distinct "identity", before they are assigned a serial
> > number, or have a MAC address or IP address programmed, etc.
> > This could be provided by some devices, such as Maxim's DS2411 "Silicon
> > serial number" ( with a "Unique, Factory-Lasered and Tested 64-Bit
> > Registration Number" ) or DS18B20 temperature sensor, ( "has a Unique
> > 64-Bit Serial Code Stored in an On-Board ROM" )
> > Looking for the least expensive chip with such an ID, with an I2C
> > (preferred), SPI or 1-wire interface. Don't care what other
> > functionality that chip may have, I just want the unique ID. A device
> > that report its own serial number would be OK.
> > Any recommendations?
> > Thanks,
> I use the Microchip 25AA02E48 in several products. It's SPI but the
> 24AA025E48 is I2C. They will run you about $0.23 in a SOT-23
> package. Get them from Mouser,Digikey,Avnet or direct from Microchip.
> Good news is you also get some EEPROM along with the MAC address.
I second the recommendation, I use both flavors of these guys a regular basis. As easy to use as any serial EEPROM and cheap.
In comp.arch.embedded Roberto Waltman <use...@rwaltman.com> wrote:
> For a project I am working on, I would like to give boards fresh from
> manufacturing a distinct "identity", before they are assigned a serial
> number, or have a MAC address or IP address programmed, etc.
> This could be provided by some devices, such as Maxim's DS2411
> "Silicon serial number" ( with a "Unique, Factory-Lasered and Tested
> 64-Bit Registration Number" ) or DS18B20 temperature sensor, ( "has a
> Unique 64-Bit Serial Code Stored in an On-Board ROM" )
> Looking for the least expensive chip with such an ID, with an I2C
> (preferred), SPI or 1-wire interface. Don't care what other
> functionality that chip may have, I just want the unique ID.
> A device that report its own serial number would be OK.
> Any recommendations?
How about using a uC with built-in unique ID? E.g. STM32F?
That's very interesting info on the 24AA025E48. We currently use a
STm24cxx256 part on our boards both to store a MAC address (and a bunch of
other programming information). We bought a block of 4096 addresses from
the IEEE, but keeping track of them all and having to program each boardset
prior to use is something of a pain.
While we need far more than the 2kbits available on the 24AA025E48, it
might be very much worthwhile adding one just for the MAC. Reading the
datasheet, it looks as if this is a valid IEEE MAC address as microchip
have registered for an OUI. Given that and the low price of the parts, I
might well be pushing for one of these on the next rev of our board as it
cuts out a programming step.
>On Fri, 10 Aug 2012 13:47:30 -0400, Roberto Waltman wrote:
>> For a project I am working on, I would like to give boards fresh from
>> manufacturing a distinct "identity", before they are assigned a serial
>> number, or have a MAC address or IP address programmed, etc.
>> This could be provided by some devices, such as Maxim's DS2411 "Silicon
>> serial number" ( with a "Unique, Factory-Lasered and Tested 64-Bit
>> Registration Number" ) or DS18B20 temperature sensor, ( "has a Unique
>> 64-Bit Serial Code Stored in an On-Board ROM" )
>> Looking for the least expensive chip with such an ID, with an I2C
>> (preferred), SPI or 1-wire interface. Don't care what other
>> functionality that chip may have, I just want the unique ID. A device
>> that report its own serial number would be OK.
>> Any recommendations?
>> Thanks,
>I use the Microchip 25AA02E48 in several products. It's SPI but the
>24AA025E48 is I2C. They will run you about $0.23 in a SOT-23
>package. Get them from Mouser,Digikey,Avnet or direct from Microchip.
>Good news is you also get some EEPROM along with the MAC address.
On Tue, 14 Aug 2012 15:35:51 -0500, Smeghead wrote:
> That's very interesting info on the 24AA025E48. We currently use a
> STm24cxx256 part on our boards both to store a MAC address (and a bunch
> of other programming information). We bought a block of 4096 addresses
> from the IEEE, but keeping track of them all and having to program each
> boardset prior to use is something of a pain.
> While we need far more than the 2kbits available on the 24AA025E48, it
> might be very much worthwhile adding one just for the MAC. Reading the
> datasheet, it looks as if this is a valid IEEE MAC address as microchip
> have registered for an OUI. Given that and the low price of the parts, I
> might well be pushing for one of these on the next rev of our board as
> it cuts out a programming step.
> Thanks for the info!
[snip]
It's trivial to use your own OUI with these parts. Just slam
yours in the 1st 3 bytes when you program the EMAC block
On Tue, 14 Aug 2012 18:38:13 -0400, Roberto Waltman <use...@rwaltman.com>
wrote:
>Uwe Bonnes wrote:
>>How about using a uC with built-in unique ID? E.g. STM32F?
>Valid for a new design. This is a respin of an existing product, and
>the CPU (untouchable) does not have an ID.
Wait a minute, they are doing a respin and the old uC is untouchable???
Hand them a flashlight and a crowbar. They are in dire need. Even in
aerospace and medical any respin is effectively a new design. New pass on
ALL qualifications.
> On Tue, 14 Aug 2012 18:38:13 -0400, Roberto Waltman<use...@rwaltman.com>
> wrote:
>> Uwe Bonnes wrote:
>>> How about using a uC with built-in unique ID? E.g. STM32F?
>> Valid for a new design. This is a respin of an existing product, and
>> the CPU (untouchable) does not have an ID.
> Wait a minute, they are doing a respin and the old uC is untouchable???
> Hand them a flashlight and a crowbar. They are in dire need. Even in
> aerospace and medical any respin is effectively a new design. New pass on
> ALL qualifications.
> ?-)
I understand that perfectly. I don't know why they are doing a board spin, but they don't want to touch any code they don't have to. Using a different MCU chip can wreak havoc on code if it turns out to have unsuspected hardware dependencies.
rickman wrote:
>I understand that perfectly. I don't know why they are doing a board >spin, but they don't want to touch any code they don't have to. Using a >different MCU chip can wreak havoc on code if it turns out to have >unsuspected hardware dependencies.
Precisely. The new and old boards share 80% of the peripherals, and
that means a lot of the code is already written, tested and known to
be reliable, if we stay with the same CPU.
--
Roberto Waltman
[ Please reply to the group,
return address is invalid ]
On Thu, 16 Aug 2012 22:19:49 -0400, Roberto Waltman <use...@rwaltman.com>
wrote:
>rickman wrote:
>>I understand that perfectly. I don't know why they are doing a board >>spin, but they don't want to touch any code they don't have to. Using a >>different MCU chip can wreak havoc on code if it turns out to have >>unsuspected hardware dependencies.
>Precisely. The new and old boards share 80% of the peripherals, and
>that means a lot of the code is already written, tested and known to
>be reliable, if we stay with the same CPU.
Well alrighty then. Family compatible could be potentially acceptable
then. Depends a lot on just which peripherals are onboard the MCU.
