Figure 169. Dfsdm_Chydatinr Registers Operation Modes And Assignment - ST STM32L4 5 Series Reference Manual

RM0351
DFSDM_CH[y+1]DATINR). The digital filters must perform two samplings - one from
channel y and one from channel (y+1) - in order to empty DFSDM_CHyDATINR
registers.
Dual mode setting (DATPACK[1:0]=2) is available only on even channel numbers (y =
0, 2, 4, 6). If odd channel (y = 1, 3, 5, 7) is set to Dual mode then both INDAT0[15:0]
and INDAT1[15:0] parts are write protected for this channel. If even channel is set to
Dual mode then the following odd channel must be set into Standard mode
(DATPACK[1:0]=0) for correct cooperation with even channels.
See Figure 169
samples to channels.

Figure 169. DFSDM_CHyDATINR registers operation modes and assignment

The write into DFSDM_CHyDATINR register to load one or two samples must be performed
after the selected input channel (channel y) is enabled for data collection (starting
conversion for channel y). Otherwise written data are lost for next processing.
For example: for single conversion and interleaved mode, do not start writing pair of data
samples into DFSDM_CHyDATINR before the single conversion is started (any data
present in the DFSDM_CHyDATINR before starting a conversion is discarded).
24.4.7 Channel selection
There are 8 multiplexed channels which can be selected for conversion using the injected
channel group and/or using the regular channel.
The injected channel group is a selection of any or all of the 8 channels. JCHG[7:0] in the
DFSDM_FLTxJCHGR register selects the channels of the injected group, where JCHG[y]=1
means that channel y is selected.
Injected conversions can operate in scan mode (JSCAN=1) or single mode (JSCAN=0). In
scan mode, each of the selected channels is converted, one after another. The lowest
channel (channel 0, if selected) is converted first, followed immediately by the next higher
channel until all the channels selected by JCHG[7:0] have been converted. In single mode
(JSCAN=0), only one channel from the selected channels is converted, and the channel
selection is moved to the next channel. Writing to JCHG[7:0] if JSCAN=0 resets the channel
selection to the lowest selected channel.
for DFSDM_CHyDATINR registers data modes and assignments of data
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