Looking at the BeagleBone’s SRM, I see that the contents of the board’s EEPROM are well defined (Board ID, Version, etc). The BeagleBone Black’s SRM, doesn’t say anything about the EEPROM’s layout, but looking at the contents of some of my boards, it seems to follow the same spec with a few changes. Is there a spec. for the BBB’s EEPROM somewhere out there?
I also see that the serial number programmed into the EEPROM is basically just the year, week, some constant ASCII characters and then an index that (I assume) resets to 0 at the beginning of each week. This makes since if there was only one manufacture building the bones, but since it is open source, there could be theoretically many people building them. Wouldn’t this lead to many boards that have identical serial numbers?
What sort of EEPROM layout are you looking for? The tables in the SRM show the address and the data. Not sure what more you need.
Yes, the serial numbers could be the same, but there is code in there for manufacturers information. We are not in the business of policing what people do with this design in their products. It is up to them to handle that.
My apologies. I had an out-of-date SRM (A4) I have what I think is the newest SRM (C1), and I do see that it has the table of addresses/lengths that I was missing. I’m talking about the EEPROM onboard the BBB, not the cape’s EEPROMs.
I didn’t expect that anyone is enforcing valid EEPROM’s as it is an open design after all, but I just don’t see any provision to avoid serial number duplicates for those who wish to do so. Am I still missing something? I don’t see anywhere to encode the manufacturer’s name in the EEPROM. Is there some other way for manufacturer’s to co-operatively assign unique numbers?
Yes, it is possible to have duplicate serial numbers. I am not aware of any SW that runs ion the board that uses that information. Every processor has a unique ID that is better suited for tracking different boards.
Serial numbers are for manufacturing use and as it contains a manufacturers information, that should be adequate, but then again it is not 100% fool proof. If people are just making clones of the board and selling it as a BeagleBone Black clone and being sold as the real thing, then we will be able to detect that pretty quickly.
Ok thanks for the info! I think what was confusing me is the fact that I assumed there were many manufactures of the board, since it is open. After more research I see that there is only one official manufacture on TI’s behalf. All others are modified and therfore not truely beagle bones or they are illegitimate clones instead of true beagle bones.
Actually, BeagleBoard.org operates outside of TI, so we are not doing it on their behalf per se. But yes, there is only one official one and one Chinese clone version from Element14.