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Re: Cortex-M1/3 SysTick/RTC
Andrew Lunn wrote:
SysTick is great for the eCos clock.
You could do a very simple HAL_DELAY_US(us) which only has 1ms
resolution. Not great, but it at least will work and gets you going.
Or you can go for implementation 3, using a 1ms calibration time
derived from the SysTick.
I have implemented the real-time-clock using the SysTick. It should work
pretty well as I found out with some simple tests. I have also used the
SysTick counter for a default implementation of the HAL_DELAY_US
function, which should be pretty accurate (0.01 us accuracy with 72mhz
clock). What bothers me though, is how to implement the SysTick
interrupt. It belongs to the default exception vectors of the Cortex
core. So I guess the architecture should define this ISR vector, but
normally these go into the variant or platform packages. How can we do that?
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