ISD94100 Series Technical Reference Manual
Sep 9, 2019
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1 = Slave mode bit count error event occurs.
Note:
If the slave select active but there is no any bus clock input, the SLVBEIF also active
when the slave select goes to inactive state. This bit will be cleared by writing 1 to it.
[5]
Reserved
Reserved. Any values read should be ignored. When writing to this field always write with
reset value.
[4]
SSLINE
Slave Select Line Bus Status (Read Only)
0 = The slave select line status is 0.
1 = The slave select line status is 1.
Note:
This bit is only available in Slave mode. If SSACTPOL (SPIn_SSCTL[2]) is set 0, and
the SSLINE is 1, the SPI slave select is in inactive status.
[3]
SSINAIF
Slave Select Inactive Interrupt Flag
0 = Slave select inactive interrupt was cleared or not occurred.
1 = Slave select inactive interrupt event occurred.
Note:
Only available in Slave mode. This bit will be cleared by writing 1 to it.
[2]
SSACTIF
Slave Select Active Interrupt Flag
0 = Slave select active interrupt was cleared or not occurred.
1 = Slave select active interrupt event occurred.
Note:
Only available in Slave mode. This bit will be cleared by writing 1 to it.
[1]
UNITIF
Unit Transfer Interrupt Flag
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 it.
[0]
BUSY
Busy Status (Read Only)
0 = SPI controller is in idle state.
1 = SPI controller is in busy state.
The following listing are the bus busy conditions:
e.
SPIn_CTL[0] = 1 and TXEMPTY = 0.
f.
For SPI Master mode, SPIn_CTL[0] = 1 and TXEMPTY = 1 but the current
transaction is not finished yet.
g.
For SPI Master mode, SPIn_CTL[0] = 1 and RXONLY = 1.
h.
For SPI Slave mode, the SPIn_CTL[0] = 1 and there is serial clock input into the
SPI core logic when slave select is active.
For SPI Slave mode, the SPIn_CTL[0] = 1 and the transmit buffer or transmit shift register
is not empty even if the slave select is inactive.
Note:
Please also check other indicators to know SPI is in idle or not.