GD32W51x User Manual
159
CK_OUT1 is seleced by CKOUT1SEL, in the Clock Configuration Register 0 (RCU_CFG0).
Table 6-1. Clock output 0 source select
Clock Source 0 Selection bits
Clock Source
00
CK_IRC16M
01
CK_LXTAL
10
CK_HXTAL
11
CK_PLLP
Table 6-2. Clock output 1 source select
Clock Source 1 Selection bits
Clock Source
00
CK_SYS
01
CK_PLLI2SR
10
CK_HXTAL
11
CK_PLLDIG
The CK_OUT0 frequency can be reduced by a configurable binary divider, controlled by the
CKOUT0DIV bits, in the Clock Configuration Register (RCU_CFG0).
The CK_OUT1 frequency can be reduced by a configurable binary divider, controlled by the
CKOUT1DIV bits, in the Clock Configuration Register (RCU_CFG0).
Voltage control
The 1.2V domain voltage in Deep-sleep mode can be controlled by DSLPVS[2:0] bit in the
Deep-sleep mode voltage register (RCU_DSV).
1.2V domain voltage selected in deep-sleep
mode
Table 6-3. 1.2V domain voltage selected in deep-sleep mode
DSLPVS[1:0]
Deep-sleep m ode voltage(V)
00
1.1
01
1.0
10
0.9
11
0.8
The RCU_DSV register are protected by Voltage Key register (RCU_VKEY). Only after write
0x1A2B3C4D to the RCU_VKEY, the RCU_DSV register can be written.
6.3.
RCU security protection
When the TrustZone security is enable, the RCU_SECP_CFG is able to RCU secure registers
from being modified by non-secure accesses.
When the Trustzone security is disabled, all
registers are non-secure. The RCU_SECP_CFG secure register and security status registers
are RAZ/WI. The TrustZone security is activated by the TZEN option bit in the FMC_OBR
register.