xr16c2850im Exar Corporation, xr16c2850im Datasheet - Page 45

• Manufacturer Part Number: xr16c2850im
• Description: Dual Uart With Tx And Rx Fifo Counters, 128 Bytes Of Fifos And Automatic Rs-485 Half Duplex Control
• Manufacturer: Exar Corporation

xr
REV. 2.1.3
F
F
IGURE
IGURE
(Unloading)
(Loading data
(Unloading)
(Loading data
*INT cleared when the ISR is read or when TX FIFO fills up to trigger level.
*INT is cleared when the ISR is read or when TX FIFO fills up to the trigger level.
into FIFO)
into FIFO)
TX
INT*
TXRDY#
IOW#
TX
INT*
TXRDY#
IOW#
24. T
25. T
RANSMIT
RANSMIT
TX FIFO
Empty
enabled
enabled
IER[1]
IER[1]
TX FIFO
Data in
Start
Bit
S
R
R
D0:D7
EADY
EADY
ISR Read
Stop
Bit
T
Start
Bit
ISR is read
S
S
& I
& I
T
D0:D7
D0:D7
WT
NTERRUPT
NTERRUPT
TX FIFO fills up
to trigger level
TX FIFO fills up
to trigger level
Stop
Bit
T
T
T
T
S
IMING
IMING
D0:D7
D0:D7
[FIFO M
[FIFO M
T
S
S
TX FIFO
45
Full
D0:D7
D0:D7
2.97V TO 5.5V DUAL UART WITH 128-BYTE FIFOS
T
T
WRI
WRI
ODE
ODE
T
T
T
, DMA M
, DMA M
T
SRT
SI
T
S
S
D0:D7
D0:D7
below trigger level
ODE
ODE
T
TX FIFO drops
WT
T
T
D
E
S
S
ISR is read
NABLED
ISABLED
D0:D7
D0:D7
below trigger level
TX FIFO drops
T
T
T
SI
]
empty location
]
FOR
FOR
At least 1
in FIFO
ISR Read
C
C
S
S
Last Data Byte
Last Data Byte
HANNELS
HANNELS
Transmitted
Transmitted
D0:D7
D0:D7
TXDMA#
TX FIFO
TXDMA
Empty
XR16C2850
T
SRT
T
T
A & B
A & B