ST STM32F101 series Reference Manual page 1067

Device electronic signature
Address offset: 0x08
Read only = 0xXXXX XXXX where X is factory-programmed
31 30 29
r r r
15 14 13
r r r
Bits 31:0 U_ID(95:64): 95:64 Unique ID bits.
1067/1128
28 27 26 25
r r r r
12 11 10 9
r r r r
DocID13902 Rev 15
24 23 22 21
U_ID(95:80)
r r r r
8 7 6 5
U_ID(79:64)
r r r r
20 19 18 17
r r r r
4 3 2 1
r r r r
RM0008
16
r
0
r