I am being asked to enhance the firmware installation program for an MCU (specifically, a Freescale MC9S12E64 - though I don't know if this matters).
The purpose of the enhanced installation is to limit the number of times the firmware can be installed. It seems the best way to do this would be to uniquely identify the specific MCU in use during firmware installation, in order to keep track in a central database.
If the MCU had a MAC address, this would seem to be feasible. Unfortunately, these MCU's have no network interface, and hence no MAC address. Looking through the manual for the MCU noted above, I cannot find an indication of a unique identifier for the MCU.
My question is: Do MCU's typically have unique identifiers associated with them - analogous to a MAC address - that can be obtained by software as firmware is burned into these devices?
Some do, some don't, it is not a given for all devices from all manufacturers.
One solution is to program your own unique identifier into whatever non-volatile storage is available at manufacture. Another method would be to include a device such as Ramtron's F-RAM serial memory, which provides a unique serial number as well as non-volatile memory. Many (possibly cheaper) serial EEPROM devices include unique ID or MACs as well (example)