ST16C654 Datasheet, PDF (43/51 Pages) Exar Corporation – 2.97V TO 5.5V QUAD UART WITH 64-BYTE FIFO

ST16C654/654D
2.97V TO 5.5V QUAD UART WITH 64-BYTE FIFO
REV. 5.0.0

FIGURE 21. TRANSMIT READY & INTERRUPT TIMING [NON-FIFO MODE] FOR CHANNELS A-D
TX
8QORDGLQJ
,(5>@
HQDEOHG
6WDUW
%LW
''
6WRS
%LW
,65 LV UHDG
''
,65 LV UHDG
''
,65 LV UHDG
INT*
7_:5,
7_:5,
7₆₅₇
7₆₅₇
TXRDY#
7_:5,
7₆₅₇
7_:7
7_:7
7_:7
IOW#
/RDGLQJ GDWD
LQWR 7+5
,17 LV FOHDUHG ZKHQ WKH ,65 LV UHDG RU ZKHQ GDWD LV ORDGHG LQWR WKH 7+5
7;1RQ),)2
FIGURE 22. RECEIVE READY & INTERRUPT TIMING [FIFO MODE, DMA DISABLED] FOR CHANNELS A-D
6WDUW
%LW
5;
$ '' 6 D0:D7 7 D0:D7 6 D0:D7 7 6 D0:D7 7 6 D0:D7 7 6 D0:D7 7
6WRS
%LW
,17
%₆₆₅
5;5'<
First Byte is
Received in
RX FIFO
7_66,
RX FIFO fills up to RX
Trigger Level or RX Data
Timeout
RX FIFO drops
below RX
Trigger Level
FIFO
Empties
7_55,
7₅₅
,25
5HDGLQJ GDWD RXW
RI 5; ),)2
5;,17'0$
43