2020-12-17 12:11 PM
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,
2020-12-17 01:42 PM
It's an internal signal, not accessible to users.
ST's documentation is not famous for being concise.
JW