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M0A21/M0A23 Series
May 06, 2022
Page
545
of 746
Rev 1.02
M0
A21
/M
0
A
2
3
SE
RIES
TEC
H
NICAL
RE
FEREN
C
E
M
ANUAL
6.14.7 Register Description
USCI Control Register (USPI_CTL)
Register
Offset
R/W
Description
Reset Value
USPI_CTL
U0x00
R/W
USCI Control Register
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
FUNMODE
Bits Description
[31:3]
Reserved
Reserved.
[2:0]
FUNMODE
Function Mode
This bit field selects the protocol for this USCI controller. Selecting a protocol that is not available or a reserved
combination disables the USCI. When switching between two protocols, the USCI has to be disabled before
selecting a new protocol. Simultaneously, the USCI will be reset when user write 000 to FUNMODE.
000 = The USCI is disabled. All protocol related state machines are set to idle state.
001 = The SPI protocol is selected.
010 = The UART protocol is selected.
100 = The I
2
C protocol is selected.
Note:
Other bit combinations are reserved.