AT32F425
Series Reference Manual
2022.03.30
Page 54
Ver 2.01
Bit 0
HICKEN
0x1
rw
High speed internal clock enable
This bit is set and cleared by software. It can also be set by
hardware when exiting Standby or Deepsleep mode. When
a HEXT clock failure occurs. This bit can also be set. When
the HICK is used as the sytem clock, this bit cannot be
cleared.
0: Disabled
1: Enabled
4.3.2
Clock configuration register (CRM_CFG)
Access: 0 to 2 wait states.
1 or 2 wait states are inserted only when the access occurs during a clock source switch.
Bit
Name
Reset value
Type
Description
Bit 31
Reserved
0
resd
Kept at its default value.
Bit 26:24
CLKOUT_SEL 0x0
rw
Clock output selection
CLKOUT_SEL[3] is the bit 16 of the CRM_MISC1 register.
0000: None
0001: Reser ved
0010: LICK
0011: LEXT
0100: SCLK
0101: HICK
0110: HEXT
0111: PLL/2
1100: PLL/4
1101: USB
1110: ADC
Bit 27
Bit 23: 22
USBDIV
0x0
rw
USB division
The PLL clock after division is used as USB clock.
000: PLL/1.5
001: Forbidden
010: PLL/2.5
011: PLL/2
100: PLL/3.5
101: PLL/3
110: PLL/4
111: PLL/4
Bit 30: 29
Bit 21: 18
PLLMULT
0x00
rw
PLL multiplication factor
000000: PLL x 2 000001: PLL x 3
000010: PLL x 4 000011: PLL x 5
……
001100: PLL x 14 001101: PLL x 15
001110: PLL x 16 001111: PLL x 16
010000: PLL x 17 010001: PLL x 18
010010: PLL x 19 010011: PLL x 20
……
111110: PLL x 63 111111: PLL x 64
Bit 17
PLLHEXTDIV
0
rw
HEXT division selection for PLL entry clock
)
0: Forbidden
1: HEXT/2
Bit 16
PLLRCS
0
rw
PLL reference clock select
0: HICK-divided clock (4MHz)
1: HEXT clock
Bit 28
Bit 15: 14
ADCDIV
0x0
rw
ADC division
The PCLK that is divided by the following factors serves
the ADC.
000: PCLK/2
001: PCLK/4
010: PCLK/6
011: PCLK/8
100: PCLK/2
101: PCLK/12
110: PCLK/8