XR68C681J-F Datasheet, PDF (57/75 Pages) Exar Corporation – CMOS Dual Channel UART(DUART)

XR68C681
Transmitting Device
RTSA
(OP0)
CTSA
(IP0)
TXDA
TXRDY_A
(OP7)
Receiving Device
IP2
(RTS-in)
OP3
(CTS-out)
RXDB
TXRDY_A
To CPU
RTSA
CTSA
RXDA
Figure 25. Block Diagram and Timing Sequence of Two DUARTs Connected
in the Transmitter-RTS Controlled Configuration.
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