I should be able to design with HSE 8MHz.
Yes without Constraints/Issues. And as I said, use PLL to reach your system frequency target.
You can use CubeMx that helps you to find your target frequencies:
@Scarlet wrote:Yes, X3 is the HSE OSC.
No, it's not the oscillator; it's just the crystal - ie, the resonant element for the oscillator.
@Scarlet wrote:Although I'm not entirely sure about the meaning of 'not provided,
It means it isn't fitted to the board:
@Scarlet wrote:I should be able to design with HSE 8MHz.
With X3 not fitted, you won't be using HSE at all - you'll be bypassing it, and using the 8MHz clock signal from the ST-Link.
@Scarlet wrote:So I can use STLink to program the microcontroller without providing an external oscillator externally?
However, the MCU requires an HSE of 8MHz for execution. Right?
The MCU doesn't require HSE at all.
HSE is just one of the many potential clock sources.
The default for the board is to bypass the HSE, and use the 8MHz clock signal provided by the ST-Link
@Scarlet wrote:Okay, I will research the differences between the two.
Unfortunately, the link in that AVRFreaks post that I referenced seems to be broken.
But here is a description of what's inside a Crystal Oscillator:
https://www.avrfreaks.net/s/topic/a5C3l000000UcE1EAK/t160729
As you can see, an oscillator is a complete active electronic circuit:
It contains a crystal plus all the active circuitry necessary to make it oscillate and give a nice, clean digital clock signal as output.
The crystal itself is just a passive component:
it requires extra active electronic circuitry to make it oscillate.
In the case of a microcontroller, the oscillator circuitry is usually inside the microcontroller chip (eg, the HSE within the STM32) - so you just need to provide the crystal externally.
Update:
From an article from SiTime describing the difference between a crystal oscillator (XO) and just a crystal (XTAL):
#CrystalVsOscillator #OscillatorVsCrystal
