Cirrus Logic EP93xx - Manual (Page 729)

DS785UM1 23-17
Copyright 2007 Cirrus Logic
Synchronous Serial Port
EP93xx User’s Guide
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DATA: Transmit / Receive FIFO:
Read - Receive FIFO
Write - Transmit FIFO
Note: The user should right-justify data when the SSP is programmed for a data size that is less
than 16 bits. Unused bits at the top are ignored by transmit logic. The receive logic
automatically right justifies.
SSPSR
Address:
0x808A_000C - Read Only
Default:
0x0000_0000
Definition:
SSPSR is a read-only status register, which contains bits that indicate the
FIFO fill status and the SSP busy status.
Bit Descriptions:
RSVD: Reserved. Unknown During Read.
BSY: SSP busy flag (read-only):
0 - SSP is idle.
1 - SSP is currently transmitting and / or receiving a frame
or the transmit FIFO is non-empty.
RFF: Receive FIFO full (read-only):
0 - Receive FIFO is not full
1 - Receive FIFO is full
RNE: Receive FIFO not empty (read-only):
0 - Receive FIFO is empty.
1 - Receive FIFO is not empty
TNF: Transmit FIFO not full (read-only):
0 - Transmit FIFO is full.
1 - Transmit FIFO is not full.
TFE: Transmit FIFO empty (read-only):
0 - Transmit FIFO is not empty
1 - Transmit FIFO is empty
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
RSVD
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
RSVD BSY RFF RNE TNF TFE