Holtek HT32F50231 User Manual page 430

32-Bit Arm ® Cortex ® -M0+ MCU
HT32F50231/HT32F50241
Bits Field
[4] SSELC
[3] SELOEN
[0] SPIEN
Rev. 1.00
Descriptions
Software Slave Select Control
0: Set the SEL output to an inactive state
1: Set the SEL output to an active state
The application software can setup the SEL output to an active or inactive state by
configuring the SSELC bit. The active level is configured by the SELAP bit in the
SPICR1 register. Note that the SSELC bit is only available when the SELOEN bit
is set to 1 for enabling the SEL output meanwhile the SELM bit is cleared to 0 for
controlling the SEL signal by software. Otherwise, the SSELC bit has no effect.
Slave Select Output Enable
0: Set the SEL signal to the input mode for multi-master mode
1: Set the SEL signal to the output mode for slave select
The SELOEN is only available in the master mode to setup the SEL signal as an
input or output signal. When the SEL signal is configured to operate in the output
mode, it is used as a slave select signal in either the hardware or software mode
according to the SELM bit setting in the SPICR1 register. The SEL signal is used
for mode fault detection in the multi-master environment when it is configured to
operate in the input mode.
SPI Enable
0: SPI interface is disabled
1: SPI interface is enabled
430 of 486 July 31, 2018