C8051F970-A-GM Datasheet, PDF (76/454 Pages) Silicon Laboratories – Low Power Capacitive Sensing MCU with up to 32 kB of Flash

C8051F97x
12. Device Identification and Unique Identifier
The C8051F97x has SFRs that identify the device family, derivative, and revision. These SFRs can be read by
firmware at runtime to determine the capabilities of the MCU that is executing code. This allows the same firmware
image to run on MCUs with different memory sizes and peripherals, and dynamically change functionality to suit
the capabilities of that MCU.
In addition to the device identification registers, a 128-bit unique identifier (UID) is preprogrammed into all devices.
The UID resides in the last sixteen bytes of XRAM. The UID can be read by firmware using MOVX instructions and
through the debug port.
Firmware can overwrite the UID during normal operation, and the bytes in memory will be automatically reinitialized
with the UID value after any device reset. Firmware using this area of memory should always initialize the memory
to a known value, as any previous data stored at these locations will be overwritten and not retained through a
reset.
Table 12.1. UID Implementation Information
Device
C8051F970
C8051F971
C8051F972
C8051F973
C8051F974
C8051F975
External Memory (XRAM) Addresses
(MSB)
0x1FFF, 0x1FFE, 0x1FFD, 0x1FFC,
0x1FFB, 0x1FFA, 0x1FF9, 0x1FF8,
0x1FF7, 0x1FF6, 0x1FF5, 0x1FF4,
0x1FF3, 0x1FF2, 0x1FF1, 0x1FF0
(LSB)
(MSB)
0x0FFF, 0x0FFE, 0x0FFD, 0x0FFC,
0x0FFB, 0x0FFA, 0x0FF9, 0x0FF8,
0x0FF7, 0x0FF6, 0x0FF5, 0x0FF4,
0x0FF3, 0x0FF2, 0x0FF1, 0x0FF0
(LSB)
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Rev 1.0