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Everything ARM and LPC
By alanraj86
#147444
Hi,

I was configuring Timer 1 for STM32F107RB.
The clock source is HSI and is at 8MHz.
Inorder to get a 1 second interrupt, i set the
prescaler (RCC_PSC) : to 800
reload_value (RCC_ARR): to 10000
But the program did not run (I was in debug mode - using IAR).
while playing around with the values, I found that the max values for which the program ran was
799 for the PSC
and 10000 for the ARR.
Why is this? Is there a limit?
Also, If I reset the prescaler value to a higher value at a later stage in the program, then the program runs.
Is there some initial setup limitations??