
Architecture
1417
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Serial Peripheral Interface (SPI)
29.2.5 Master Mode Settings
The four master mode options are defined by the configuration bit settings listed in
. Other
configuration bits may take any value in the range listed in
. The values listed in
and
should not be changed while the ENABLE bit in the SPI global control register 1 (SPIGCR1) is
set to 1. Note that in certain cases the allowed values may still be ignored. For example,
indicates that SPIDELAY may take a range of values in Master 3-pin mode; however, SPIDELAY has no
effect in Master 3-pin mode. For complete details on each mode, see the following sections that explain
the SPI operation for each of the master modes.
Table 29-3. SPI Register Settings Defining Master Modes
Register
Bit(s)
Master 3-pin
Master 4-pin
Chip Select
Master 4-pin Enable
Master 5-pin
SPIGCR0
RESET
1
1
1
1
SPIGCR1
ENABLE
1
1
1
1
SPIGCR1
LOOPBACK
0
0
0
0
SPIGCR1
CLKMOD
1
1
1
1
SPIGCR1
MASTER
1
1
1
1
SPIPC0
SOMIFUN
1
1
1
1
SPIPC0
SIMOFUN
1
1
1
1
SPIPC0
CLKFUN
1
1
1
1
SPIPC0
ENAFUN
0
0
1
1
SPIPC0
SCS0FUN
0
1
0
1
Table 29-4. Allowed SPI Register Settings in Master Modes
Register
Bit(s)
Master 3-pin
Master 4-pin
Chip Select
Master 4-pin Enable
Master 5-pin
SPIINT0
ENABLEHIGHZ
0,1
0,1
0,1
0,1
SPIFMT
n
WDELAY
0 to 3Fh
0 to 3Fh
0 to 3Fh
0 to 3Fh
SPIFMT
n
PARPOL
0,1
0,1
0,1
0,1
SPIFMT
n
PARENA
0,1
0,1
0,1
0,1
SPIFMT
n
WAITENA
0
0
1
1
SPIFMT
n
SHIFTDIR
0,1
0,1
0,1
0,1
SPIFMT
n
DISCSTIMERS
0,1
0,1
0,1
0,1
SPIFMT
n
POLARITY
0,1
0,1
0,1
0,1
SPIFMT
n
PHASE
0,1
0,1
0,1
0,1
SPIFMT
n
PRESCALE
2 to FFh
2 to FFh
2 to FFh
2 to FFh
SPIFMT
n
CHARLEN
2 to 10h
2 to 10h
2 to 10h
2 to 10h
SPIDELAY
C2TDELAY
0 to FFh
0 to FFh
0 to FFh
0 to FFh
SPIDELAY
T2CDELAY
0 to FFh
0 to FFh
0 to FFh
0 to FFh
SPIDELAY
T2EDELAY
0 to FFh
0 to FFh
0 to FFh
0 to FFh
SPIDELAY
C2EDELAY
0 to FFh
0 to FFh
0 to FFh
0 to FFh
29.2.5.1 Master Mode Timing Options
The SPI in master mode supports several options to modify the timing of its generation of the chip select
signal (SPIx_SCS[n]). This allows the SPI to support the timing requirements of various slave devices
without adding additional overhead to the CPU by generating the appropriate delays automatically.