XR16V654/654D
48
2.25V TO 3.6V QUAD UART WITH 64-BYTE FIFO
REV. 1.0.1
FIGURE 22. TRANSMIT READY & INTERRUPT TIMING [NON-FIFO MODE] FOR CHANNELS A-D
FIGURE 23. RECEIVE READY & INTERRUPT TIMING [FIFO MODE, DMA DISABLED] FOR CHANNELS A-D
TX
TXRDY#
IOW#
INT*
D0:D7
Start
Bit
D0:D7
Stop
Bit
D0:D7
T
WT
TXNonFIFO
T
WT
T
WT
T
WRI
T
WRI
T
WRI
T
SRT
T
SRT
T
SRT
*INT is cleared when the ISR is read or when data is loaded into the THR.
ISR is read
(Loading data
into THR)
(Unloading)
IER[1]
enabled
RX
RXRDY#
IOR#
INT
D0:D7
S
T
SSR
RXINTDMA#
RX FIFO fills up to RX
Trigger Level or RX Data
Timeout
RX FIFO drops
below RX
Trigger Level
FIFO
Empties
First Byte is
Received in
RX FIFO
D0:D7
S
D0:D7
T
D0:D7
S
D0:D7
S
T
D0:D7
S
T
D0:D7
S
T
Start
Bit
Stop
Bit
T
RR
T
RRI
T
SSI
(Reading data out
of RX FIFO)