xr17v254 Exar Corporation, xr17v254 Datasheet - Page 65

• Manufacturer Part Number: xr17v254
• Description: 66mhz Pci Bus Quad Uart With Power Management Support
• Manufacturer: Exar Corporation

REV. 1.0.0
F
F
IGURE
IGURE
Transmit Trigger Level
24. T
25. R
RX Data Ready Interrupt at
TX Interrupt at
Receive Trigger Level
RX Data Input
TX Data
RANSMIT
ECEIVE
D
D
ATA
ATA
R
START
I
EADY
NTERRUPT AT
BIT
START
BIT
66MHZ PCI BUS QUAD UART WITH POWER MANAGEMENT SUPPORT
I
NTERRUPT AT
D0
Trigger Level
Set at Below
D0
D1
T
5 DATA BITS
BAUD RATE CLOCK of 16X or 8X
D1
RIGGER
6 DATA BITS
D2
7 DATA BITS
DATA BITS (5-8)
DATA BITS (5-8)
D2
T
below trigger level
RIGGER
De-asserted at
L
D3
EVEL
D3
65
L
D4
EVEL
D4
D5
Trigger Level
D5
Clear at
Above
D6
D6
D7
D7
PARITY
PARITY
BIT
BIT
STOP
STOP
BIT
BIT
First byte that
above trigger
reaches the
trigger level
Asserted at
START
NEXT
DATA
BIT
level
TXNOFIFO-1
XR17V254
RXFIFO1