ST STM32F410 User Manual

Reset and clock control (RCC) RM0401
102/771 RM0401 Rev 3
5.3 RCC registers
Refer to Section 1.2: List of abbreviations for registers for a list of abbreviations used in
register descriptions.
5.3.1 RCC clock control register (RCC_CR)
Address offset: 0x00
Reset value: 0x0000 XX81 where X is undefined.
Access: no wait state, word, half-word and byte access
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Res. Res. Res. Res. Res. Res. PLLRDY PLLON Res. Res. Res. Res.
CSS
ON
HSE
BYP
HSE
RDY
HSE ON
rrw rwrwrrw
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
HSICAL[7:0] HSITRIM[4:0] Res.
HSI
RDY
HSION
rrrrrrr rrwrwrwrwrw rrw
Bits 31:26 Reserved, must be kept at reset value.
Bit 25 PLLRDY: Main PLL (PLL) clock ready flag
Set by hardware to indicate that PLL is locked.
0: PLL unlocked
1: PLL locked
Bit 24 PLLON: Main PLL (PLL) enable
Set and cleared by software to enable PLL.
Cleared by hardware when entering Stop or Standby mode. This bit cannot be reset if PLL
clock is used as the system clock.
0: PLL OFF
1: PLL ON
Bits 23:20 Reserved, must be kept at reset value.
Bit 19 CSSON: Clock security system enable
Set and cleared by software to enable the clock security system. When CSSON is set, the
clock detector is enabled by hardware when the HSE oscillator is ready, and disabled by
hardware if an oscillator failure is detected.
0: Clock security system OFF (Clock detector OFF)
1: Clock security system ON (Clock detector ON if HSE oscillator is stable, OFF if not)
Bit 18 HSEBYP: HSE clock bypass
Set and cleared by software to bypass the oscillator with an external clock. The external
clock must be enabled with the HSEON bit, to be used by the device.
The HSEBYP bit can be written only if the HSE oscillator is disabled.
0: HSE oscillator not bypassed
1: HSE oscillator bypassed with an external clock
Bit 17 HSERDY: HSE clock ready flag
Set by hardware to indicate that the HSE oscillator is stable. After the HSEON bit is cleared,
HSERDY goes low after 6 HSE oscillator clock cycles.
0: HSE oscillator not ready
1: HSE oscillator ready

ST STM32F410 Specifications

General

Brand	ST
Model	STM32F410
Category	Microcontrollers
Language	English