17.4.6 SPI0FCN1: SPI0 FIFO Control 1
Bit
7
6
5
4
3
2
1
0
Name
TFRQ
THPOL
TXHOLD
SPIFEN
RFRQ
Reserved
RXTOE
RXFIFOE
Access
R
RW
RW
RW
R
R
RW
RW
Reset
1
1
0
1
0
0
0
1
SFR Page = 0x20; SFR Address: 0x9B
Bit
Name
Reset
Access Description
7
TFRQ
1
R
Transmit FIFO Request.
Set to 1 by hardware when the number of bytes in the TX FIFO is less than or equal to the TX FIFO threshold (TXTH).
Value
Name
Description
0
NOT_SET
The number of bytes in the TX FIFO is greater than TXTH.
1
SET
The number of bytes in the TX FIFO is less than or equal to TXTH.
6
THPOL
1
RW
Transmit Hold Polarity.
Selects the polarity of the data out signal when TXHOLD is active.
Value
Name
Description
0
HOLD_0
Data output will be held at logic low when TXHOLD is set.
1
HOLD_1
Data output will be held at logic high when TXHOLD is set.
5
TXHOLD
0
RW
Transmit Hold.
This bit allows firmware to stall transmission of bytes from the TX FIFO until cleared. When set, the SPI will complete any
byte transmission in progress, but any new transfers will be 0xFF, and not pull data from the TX FIFO. Bytes will continue
to be pulled from the TX FIFO when the TXHOLD bit is cleared.
Value
Name
Description
0
CONTINUE
The UART will continue to transmit any available data in the TX FIFO.
1
HOLD
The UART will not transmit any new data from the TX FIFO.
4
SPIFEN
1
RW
SPIF Interrupt Enable.
When set to 1, a SPI0 interrupt will be generated any time SPIF is set to 1.
Value
Name
Description
0
DISABLED
SPI0 interrupts will not be generated when SPIF is set.
1
ENABLED
SPI0 interrupts will be generated if SPIF is set.
3
RFRQ
0
R
Receive FIFO Request.
Set to 1 by hardware when the number of bytes in the RX FIFO is larger than specified by the RX FIFO threshold (RXTH).
Value
Name
Description
0
NOT_SET
The number of bytes in the RX FIFO is less than or equal to RXTH.
1
SET
The number of bytes in the RX FIFO is greater than RXTH.
2
Reserved
Must write reset value.
EFM8UB3 Reference Manual
Serial Peripheral Interface (SPI0)
silabs.com
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