xr16v554 Exar Corporation, xr16v554 Datasheet - Page 37

• Manufacturer Part Number: xr16v554
• Description: 2.25v To 3.6v Quad Uart With 16-byte Fifo
• Manufacturer: Exar Corporation

REV. 1.0.2
F
F
IGURE
IGURE
RXRDY#
RX
INT
IOR#
(Reading data out
of RX FIFO)
(Unloading)
(Loading data
*INT is cleared when the ISR is read or when TX FIFO fills up to the trigger level.
into FIFO)
TX
INT*
TXRDY#
IOW#
21. R
22. T
RANSMIT
ECEIVE
TX FIFO
Empty
enabled
IER[1]
Start
Bit
S
TX FIFO
Data in
D0:D7
R
R
EADY
Trigger Level or RX Data
EADY
RX FIFO fills up to RX
Stop
Bit
S
& I
Start
Bit
ISR is read
S
& I
Timeout
D0:D7
NTERRUPT
T
D0:D7
WT
NTERRUPT
TX FIFO fills up
to trigger level
Stop
T
Bit
T
T
D0:D7
T
IMING
T
S
IMING
SSI
D0:D7
[FIFO M
S
[FIFO M
T
T
SSR
D0:D7
S
37
D0:D7
T
WRI
ODE
2.25V TO 3.6V QUAD UART WITH 16-BYTE FIFO
T
ODE
T
, DMA E
S
, DMA M
T
SI
D0:D7
T
S
D0:D7
NABLED
T
below trigger level
ODE
TX FIFO drops
S
T
RRI
D0:D7
T
D
S
ISR is read
]
ISABLED
FOR
D0:D7
T
RX FIFO drops
Trigger Level
C
below RX
S
T
HANNELS
]
D0:D7
FOR
XR16V554/554D
Empties
C
T
S
Last Data Byte
RR
T
FIFO
HANNELS
Transmitted
D0:D7
A-D
RXFIFODMA
TXDMA#
TX FIFO
Empty
T
SRT
T
A-D