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M0A21/M0A23 Series
May 06, 2022
Page
549
of 746
Rev 1.02
M0
A21
/M
0
A
2
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SE
RIES
TEC
H
NICAL
RE
FEREN
C
E
M
ANUAL
USCI Input Control Signal Configuration (USPI_CTLIN0)
Register
Offset
R/W Description
Reset Value
USPI_CTLIN0
U0x20
R/W USCI Input Control Signal Configuration Register 0
0x0000_0000
31
30
29
28
27
26
25
24
Reserved
23
22
21
20
19
18
17
16
Reserved
15
14
13
12
11
10
9
8
Reserved
7
6
5
4
3
2
1
0
Reserved
ININV
Reserved
SYNCSEL
Bits Description
[31:3]
Reserved
Reserved.
[2]
ININV
Input Signal Inverse Selection
This bit defines the inverter enable of the input asynchronous signal.
0 = The un-synchronized input signal will not be inverted.
1 = The un-synchronized input signal will be inverted.
[1]
Reserved
Reserved.
[0]
SYNCSEL
Input Synchronization Signal Selection
This bit selects if the un-synchronized input signal (with optionally inverted) or the synchronized (and optionally
filtered) signal, which is synchronized with PCLK, can be used as input for the data shift unit.
0 = The un-synchronized signal can be taken as input for the data shift unit.
1 = The synchronized signal can be taken as input for the data shift unit.
Note:
In SPI protocol, it is suggested this bit should be set as 0.