Difference between revisions of "STM32F107VC/RCC"
From Teknologisk videncenter
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*HSI clock divided by 2 | *HSI clock divided by 2 | ||
*HSE or PLL2 clock through a configurable divider | *HSE or PLL2 clock through a configurable divider | ||
| − | + | =Example= | |
| + | *[http://mars.tekkom.dk/data/startup%20clock.zip Clock mode 1 and clock mode 5 example] | ||
__NOTOC__ | __NOTOC__ | ||
[[Category:STM32F107VC]][[Category:ARM]] | [[Category:STM32F107VC]][[Category:ARM]] | ||
Revision as of 12:14, 19 September 2011
RCC - reset and clock control
STM32F107VC is a Connectivity Line Device and this register refers to Chapter 8 in The Reference manual.
Reset
There are three types of reset
- System Reset
- Power Reset
- Backup Domain Reset
Se section 8.1 of the The Reference manual for further information.
Clocks
Three different clock sources can be used to drive the system clock (SYSCLK):
- HSI oscillator clock
- HSE oscillator clock
- PLL clock
Clock Modes
- The SYSCLK and Cortex M3 Clock can be configured in five different paths. See Clock Paths
- Clock Modes example
HSI - High Speed Internal Clock
The HSI clock signal is generated from an internal 8 MHz RC Oscillator and can be used directly as a system clock or divided by 2 to be used as PLL input.
| Name | Section | Name | r/w | Bits | Function |
|---|---|---|---|---|---|
| RCC_RC | 8.3.1 | Clock Control Register | rw/r | HSICAL[7:0],HSITRIM[4:0] HSIRDY,HSION | HSI ON and calibration |
HSE - High Speed External clock
The high speed external clock signal (HSE) can be generated from two possible clock sources:
- HSE external crystal/ceramic resonator
- HSE user external clock
The MCBSTM32C evaluation board has a 25Mhz on board crystal for HSE Clock.
PLL - Phase Locked Loops
The main PLL provides a frequency multiplier starting from one of the following clock sources:
- HSI clock divided by 2
- HSE or PLL2 clock through a configurable divider