PRC3=0, PRC0=0, PRKEY=others, PRC1=0
Protect Register
| PRC0 | Enables writing to the registers related to the clock generation circuit. 0 (0): Writes protected. 1 (1): Writes not protected. |
| PRC1 | Enables writing to the registers related to the operating modes, the low power consumption modes and the battery backup function. 0 (0): Writes protected. 1 (1): Writes not protected. |
| Reserved | This bit is read as 0. The write value should be 0. |
| PRC3 | Enables writing to the registers related to the LVD. 0 (0): Writes protected. 1 (1): Writes not protected. |
| Reserved | These bits are read as 0000. The write value should be 0000. |
| PRKEY | PRKEY Key Code 0 (others): Disables writing to the PRCR register. 90 (0x5A): Enables writing to the PRCR register. |