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				STM32f411CE  RCC / Timings
				Posted: Sat Apr 20, 2024 1:19 am
				by Alan_37
				Hello 
I  am using  STM32f411CE  there is something wrong with the RCC Settings in Flowcode 
I use STM32 Cube MX  to calculate the setting  no matter what settings I put HSI or HSE 
if I  simply  make a Loop with a C13=1,  300ms delay, C13=0,   300ms Delay,  I always get 45ms Delay 
when measuring with oscilloscope no matter what setting I put .
I also tried 16mhz HSI  direct everything /1 same result .
Any help Please .
			 
			
					
				Re: STM32f411CE  RCC / Timings
				Posted: Sat Apr 20, 2024 8:56 am
				by LeighM
				Have you set the clock speed in project settings, to the frequency of the external crystal?
Just checking  
 
Otherwise, could you post an example project?
 
			 
			
					
				Re: STM32f411CE  RCC / Timings
				Posted: Sat Apr 20, 2024 11:15 am
				by Alan_37
				Hi , LeighM
Yes I have set the clock speed  LOL , 
I just found it , it was the Auto clear watchdog  selected in the options 
removing it all works fine now, still don't know why that would happen .
I also wanted to ask why the 411 is limited to 26Mhz in Flowcode  
when in the data sheet say it can go up to 100Mhz with PLL
			 
			
					
				Re: STM32f411CE  RCC / Timings
				Posted: Sat Apr 20, 2024 12:57 pm
				by LeighM
				Ah, well done.
As there are a number of internal clocks, everything relates to the input clock frequency (internal, or external crystal)
So it's the input clock frequency that is limited to 26Mhz (and is set in the project options clock speed)
			 
			
					
				Re: STM32f411CE  RCC / Timings
				Posted: Sat Apr 20, 2024 7:23 pm
				by Alan_37
				So if I set the clock frequency say to 70Mhz via PLL and in flowcode options 
I write 25Mhz cos  that is the external oscillator frequency  , Will flowcode be able to 
calculate the right timings  ?
			 
			
					
				Re: STM32f411CE  RCC / Timings
				Posted: Sat Apr 20, 2024 10:00 pm
				by LeighM
				Yes, that's correct
			 
			
					
				Re: STM32f411CE  RCC / Timings
				Posted: Thu Apr 25, 2024 8:16 am
				by Alan_37
				Ok I  see , 
Coming from Mcu's like AVR that dose not have PLL ,  I did not know that  flowcade can calculate the internal PLL clocks 
well that's cool 
 
Maybe a for next update may I suggests  flowcode displaying the calculated PLL clocks that would be nice .
Thanks