Question on McuSysClkFrequency – MCAL

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nsyed
Level 5
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I started MCAL configuring for TC377 device. I wanted to know what does the below configuration define ?

I understand McuMainOscillatorFrequency defines the XTAL1/XTAL2 oscillator frequency, however what is SysClkFrequency ?
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NeMa_4793301
Level 6
Level 6
10 likes received 10 solutions authored 5 solutions authored
See 10.8 Clock Generation Unit in the User Manual, and SYSPLLCON0.INSEL: it's possible to use the SYSCLK input to drive the System PLL and Peripheral PLL.

Most applications use a crystal on XTAL1/XTAL2, or an External Input Clock on XTAL1, instead of using SYSCLK. For those, you'd use McuMainOscillatorFrequency.
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nsyed
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Ok thanks, this makes sense.

I was completely thrown off by section 10.3 - Clock Sources.Section 10.3 talks about Oscillator and Back-Up Clock source, but does not mention anything about SYSCLK.
I am not sure if we can raise a request to modify the Reference manual. Probably add a small section 10.3.3 to talk something about SYSCLK, this could have saved a lot of time (at least for me).
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