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STM32F103C8 What is CNT_INIT in General Purpose Timers?

AAnth.1
Senior

Hi

Figure 120 in the reference manual RM0008 shows the control circuit in normal mode. It shows an update event using the Update Generation bit (UG). See attached figure.

I am curious about the CNT_INIT bit, which is a pulse one clock cycle after the UG bit has been set. One clock cycle after the CNT_INIT bit, the counter clock is reset and starts over again. From what I understand, it takes two clock cycles, whereas in normal update event (UEV), it takes only one clock cycle to reset the counter register.

I can not find any documentation, yet the CNT_INIT bit in the reference manual nor in the AppNotes AN4776 and AN4013. I can guess that CNT_INIT stands for counter initialize, and that when that bit is set, that the counter gets reset. But it would be nice to have it written since it's a fundamental difference to the regular UEV.

Unless I am overseeing something fundamental, the CNT_INIT bit is a mysterious bit that exists but no one knows about it.

Is that the intention?

Thank you,

0693W000006GD5oQAG.png

1 REPLY 1

It's an internal signal, not accessible to users.

ST's documentation is not famous for being concise.

JW