Renesas SH7781 - Manual (Page 1188)

23. Serial Peripheral Interface (HSPI)
Rev.1.00 Jan. 10, 2008 Page 1158 of 1658
REJ09B0261-0100
23.3.2 Status Register (SPSR)
SPSR is a 32-bit readable/writable register. Through the status flags in SPSR, it can be confirmed
whether or not the system is correctly operating. If the ROIE bit in SPSCR is set to 1, an interrupt
request is generated due to the occurrence of the receive buffer overrun error or the warning of the
receive buffer overrun error. When the TFIE bit in SPSCR is set to 1, an interrupt request is
generated by the transmit complete status flag. If the appropriate enable bit in SPSCR is set to 1,
an interrupt request is generated due to the receive FIFO halfway, receive FIFO full, transmit
FIFO empty, or transmit FIFO halfway flag. If the RNIE bit in SPSCR is set to 1, an interrupt
request is generated when the receive FIFO is not empty.
16 17 18 19 20 21 22 23 24 25 26 27 28 29 31 30
— — — — — — — — — — — — — — — —
R R R R R R R R R R R R R R R R
Bit:
Initial value:
R/W:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 15 14
0 0 0 0 0 1 0 0 1 0 0
TXFL TXFN RXFL RXOW RXOO RXEM RXHA RXFU TXEM TXHA TXFU — — — — —
— — — — — — — — — — — — — — — —
— — — — —
R R R R/W* R/W* R R R R R R R R R R R
Bit:
Initial value:
R/W:
Bit Bit Name
Initial
Value R/W
Description
31 to 11
⎯ Undefined
R Reserved
These bits are always read as an undefined value. The
write value should always be 0.
10 TXFU 0 R Transmit FIFO Full Flag
This status flag is enabled only in FIFO mode. The flag
is set to 1 when the transmit FIFO is full of bytes for
transmission and cannot accept any more. It is cleared
to 0 when data is transmitted from the transmit FIFO to
the HSPI bus.
9 TXHA 0 R Transmit FIFO Halfway Flag
This status flag is enabled only in FIFO mode. The flag
is set to 1 when the transmit FIFO reaches the halfway
point, that is, it has four bytes of data and free space for
four bytes of data. It is cleared to 0 when more data is
written to the transmit FIFO. It remains set to 1 until
cleared to 0 even if data stored in the FIFO becomes
less than four bytes (halfway point).
If TXHA = 1 and THIE = 1, an interrupt is generated.