ISD91200 Series Technical Reference Manual
Release Date: Sep 16, 2019
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Revision 2.4
[4]
SSLINE
Slave Select Line Bus Status (Read Only)
0 = Indicates the slave select line bus status is 0.
1 = Indicates the slave select line bus status is 1.
Note: If SPI0_SSCTL.SSACTPOL is set 0, and the SSLINE is 1, the SPI slave select is in
inactive status.
[3]
SSINAIF
Slave Select Inactive Interrupt Status
0 = Slave select inactive interrupt is clear or not occur.
1 = Slave select inactive interrupt event has occur.
Note: This bit will be cleared by writing 1 to itself.
[2]
SSACTIF
Slave Select Active Interrupt Status
0 = Slave select active interrupt is clear or not occur.
1 = Slave select active interrupt event has occur.
Note: This bit will be cleared by writing 1 to itself.
[1]
UNITIF
Unit Transfer Interrupt Status
0 = No transaction has been finished since this bit was cleared to 0.
1 = SPI controller has finished one unit transfer.
Note: This bit will be cleared by writing 1 to itself.
[0]
BUSY
SPI Unit Bus Status (Read Only)
0 = No transaction in the SPI bus.
1 = SPI controller unit is in busy state.
The following listing are the bus busy conditions:
SPIEN = 1 and the TXEMPTY = 0.
For SPI Master, the TXEMPTY = 1 but the current transaction is not finished yet.
For SPI Slave receive mode, the SPIEN = 1 and there is serial clock input into the SPI
core logic when slave select is active.
For SPI Slave transmit mode, the SPIEN = 1 and the transmit buffer is not empty in SPI
core logic event if the slave select is inactive.
