XRT16C854 Datasheet, PDF (47/54 Pages) Exar Corporation – 2.97V TO 5.5V QUAD UART WITH 128-BYTE FIFO

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REV. 3.0.1
XR16C854/854D
2.97V TO 5.5V QUAD UART WITH 128-BYTE FIFO
FIGURE 22. RECEIVE READY & INTERRUPT TIMING [FIFO MODE, DMA DISABLED] FOR CHANNELS A-D
Start
Bit
RX
S D0:D7 S D0:D7 T
D0:D7 S D0:D7 T S D0:D7 T S D0:D7 T S D0:D7 T
Stop
Bit
INT
T_SSR
RXRDY#
First Byte is
Received in
RX FIFO
T_SSI
RX FIFO fills up to RX
Trigger Level or RX Data
Timeout
RX FIFO drops
below RX
Trigger Level
FIFO
Empties
T_RRI
T_RR
IOR#
(Reading data out
of RX FIFO)
RXINTDMA#
FIGURE 23. RECEIVE READY & INTERRUPT TIMING [FIFO MODE, DMA ENABLED] FOR CHANNELS A-D
RX
INT
RXRDY#
Start
Bit
Stop
Bit
S D0:D7 S D0:D7 T
D0:D7 S D0:D7 T S D0:D7 T S D0:D7 T S D0:D7 T
T_SSI
RX FIFO drops
below RX
Trigger Level
RX FIFO fills up to RX
Trigger Level or RX Data
T_SSR
Timeout
FIFO
Empties
IOR#
(Reading data out
of RX FIFO)
T_RRI
T_RR
RXFIFODMA
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