There are three conversion modes available for this module; normal conversion, injected
conversion and CTU triggered conversion. CTU triggered conversion will be explained in the
chapter dedicated to the CTU module, this section is only about normal and injected modes.
1.2.1. Normal Conversion
A normal conversion can be started from the software by setting the NSTART (Normal Start) bit
of the control register. There are two operating modes available for the normal conversion; one
shot and scan modes.
In one shot mode, a sequential conversion of the channels configured for the normal conversion
is performed only once and the resulting data is stored in data registers. The NSTART bit is reset
once the conversion starts, allowing the software to start another conversion. If the previous
conversion is not finished while a new one is requested, then the new conversion will be done
right after the old one is done.
Figure 65 : Normal conversion flow of channels B, C, D and E (R.M. Rev8 – Fig. 25-2)
In scan mode, the sequential conversion of these channels is continuously executed, NSTART bit
is automatically set once the conversion starts and it is not reset. The software can clear it to
stop the conversion. At the end of each conversion, an End of Conversion interrupt is triggered,
allowing the data to be processed, and at the end of the conversion of the whole sequence, an
End of Chain interrupt is triggered.
1.2.2. Injected Conversion
Injected conversions can only occur in one shot mode, it interrupts ongoing normal conversions.
Once the conversions of the injected channels are completed, the normal conversion resumes
from where it was left.
Figure 66 : Injected mode illustration (R.M. Rev8 – Fig. 25-3)
This mode can be starter using either the JSTART bit from the software, in a very similar way
with the normal conversion, or using a trigger signal from the PIT 2, having JTRGEN (injected
trigger enable) set. This mode can be configured to start at a rising or falling edge on the signal
coming from PIT (JSTART is automatically set).
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