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STM32F303CB Unique Device ID - false values?

Question asked by rnaegeli on Apr 27, 2016
Latest reply on Apr 30, 2016 by wolff.roger
Hi

I am reading from different STM32F303CB the unique device IDs as follows:

// unique device ID base address from RM p.1120
#define BASE_ADDR_UID ((uint32_t *)0x1FFFF7AC)   
  
uint32_t UID_Low  = BASE_ADDR_UID[0];
uint32_t UID_Mid  = BASE_ADDR_UID[1];
uint32_t UID_High = BASE_ADDR_UID[2];

I got following values:
                                                                                                                                                                                                                                                                                                                                       
  UID_HighUID_Mid UID_Low 
 uC 120 34 36 3457 32 57 070025 0023
 uC 220 34 36 3457 32 57 07001F 002F
 uC 320 34 36 3457 32 57 040022 0036
 uC 420 36 35 3250 33 57 11003F 0026

There is a description in the reference manual, what these values mean:
Reference manual

UID [31:0]:    
X/Y coordinates on Wafer (BCD coded)

UID [39:32]:      
Wafer number (8-bit unsigned number)

UID [95:40]:
LOT number (ASCII encoded)

Problem:
In my UID_Low shall be the X/Y coordinates coded in BCD. But 0xF in BCD does not exist.
In addition, the highest byte of the LOT number is a space (0x20).

Is the reference manual information false or am I doing/understanding something wrong?

I hope you can help me.

Thank you and best regards

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