ST STM32L0x3 User Manual

RM0367 Rev 7 193/1043
RM0367 Reset and clock control (RCC)
225
Bits 21:18 PLLMUL[3:0]: PLL multiplication factor
These bits are written by software to define the PLL multiplication factor to generate the PLL
VCO clock. These bits can be written only when the PLL is disabled.
0000: PLLVCO = PLL clock entry x 3
0001: PLLVCO = PLL clock entry x 4
0010: PLLVCO = PLL clock entry x 6
0011: PLLVCO = PLL clock entry x 8
0100: PLLVCO = PLL clock entry x 12
0101: PLLVCO = PLL clock entry x 16
0110: PLLVCO = PLL clock entry x 24
0111: PLLVCO = PLL clock entry x 32
1000: PLLVCO = PLL clock entry x 48
others: not allowed
Caution: The PLL VCO clock frequency must not exceed 96 MHz when the product is in
Range 1, 48 MHz when the product is in Range 2 and 24 MHz when the product is in
Range 3.
Bit 17 Reserved, must be kept at reset value.
Bit 16 PLLSRC: PLL entry clock source
This bit is set and cleared by software to select PLL clock source. This bit can be written only
when PLL is disabled.
0: HSI16 oscillator clock selected as PLL input clock
1: HSE oscillator clock selected as PLL input clock
Note: The PLL minimum input clock frequency is 2 MHz.
Bit 15 STOPWUCK: Wake-up from Stop clock selection
This bit is set and cleared by software to select the wake-up from Stop clock.
0: internal 64 KHz to 4 MHz (MSI) oscillator selected as wake-up from Stop clock
1: internal 16 MHz (HSI16) oscillator selected as wake-up from Stop clock (or HSI16/4 if
HSI16DIVEN=1)
Bit 14 Reserved, must be kept at reset value.
Bits 13:11 PPRE2[2:0]: APB high-speed prescaler (APB2)
These bits are set and cleared by software to control the division factor of the APB high-
speed clock (PCLK2).
0xx: HCLK not divided
100: HCLK divided by 2
101: HCLK divided by 4
110: HCLK divided by 8
111: HCLK divided by 16
Bits 10:8 PPRE1[2:0]: APB low-speed prescaler (APB1)
These bits are set and cleared by software to control the division factor of the APB low-speed
clock (PCLK1).
0xx: HCLK not divided
100: HCLK divided by 2
101: HCLK divided by 4
110: HCLK divided by 8
111: HCLK divided by 16

ST STM32L0x3 Specifications

General

Brand	ST
Model	STM32L0x3
Category	Microcontrollers
Language	English