XR17C152 Datasheet, PDF (57/62 Pages) Exar Corporation – 5V PCI BUS DUAL UART

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REV. 1.2.0
XR17C152
5V PCI BUS DUAL UART
FIGURE 22. TRANSMIT DATA INTERRUPT AT TRIGGER LEVEL
START
BIT
DATA BITS (5-8)
STOP
BIT
TX Data
D0 D1 D2 D3 D4 D5 D6 D7
5 DATA BITS
PARITY
BIT
6 DATA BITS
7 DATA BITS
NEXT
DATA
START
BIT
TX Interrupt at
Transmit Trigger Level
Set at Below
Trigger Level
Clear at
Above
Trigger Level
BAUD RATE CLOCK of 16X or 8X
TXNOFIFO-1
FIGURE 23. RECEIVE DATA READY INTERRUPT AT TRIGGER LEVEL
RX Data Input
START
BIT
DATA BITS (5-8)
STOP
BIT
D0 D1 D2 D3 D4 D5 D6 D7
PARITY First byte that
BIT reaches the
trigger level
RX Data Ready Interrupt at
Receive Trigger Level
De-asserted at
below trigger level
Asserted at
above trigger
level
RXFIFO1
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