XRT16C854 Datasheet, PDF (25/54 Pages) Exar Corporation – 2.97V TO 5.5V QUAD UART WITH 128-BYTE FIFO

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REV. 3.0.1
XR16C854/854D
2.97V TO 5.5V QUAD UART WITH 128-BYTE FIFO
TABLE 9: INTERNAL REGISTERS DESCRIPTION. SHADED BITS ARE ENABLED WHEN EFR BIT-4=1
ADDRESS REG READ/
A2-A0 NAME WRITE
BIT-7
BIT-6
BIT-5
BIT-4
BIT-3 BIT-2 BIT-1 BIT-0 COMMENT
Baud Rate Generator Divisor
000
001
DLL RD/WR
DLM RD/WR
Bit-7
Bit-7
Bit-6
Bit-6
Bit-5
Bit-5
Bit-4
Bit-4
Bit-3
Bit-3
Bit-2
Bit-2
Bit-1
Bit-1
Bit-0 LCR[7] = 1
LCR ≠ 0xBF
Bit-0
0 0 0 DREV RD
0 0 1 DVID RD
Bit-7
0
Bit-6
0
Bit-5
0
Bit-4
1
Bit-3
0
Bit-2
1
Bit-1
0
Bit-0
0
LCR[7] = 1
LCR ≠ 0xBF
DLL=0x00
DLM=0x00
Enhanced Registers
0 0 0 TRG WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
000
FC
RD Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
001
FCTR RD/WR RX/TX SCPAD
Mode Swap
Trig
Table
Bit-1
Trig
Table
Bit-0
Auto
RS485
Direction
Control
RX IR
Input
Inv.
Auto
RTS
Hyst
Bit-1
Auto
RTS
Hyst
Bit-0
010
EFR
RD/WR Auto
CTS#
Enable
Auto
RTS#
Enable
Special
Char
Select
Enable
IER [7:4],
ISR [5:4],
FCR[5:4],
MCR[7:5]
Soft-
ware
Flow
Cntl
Bit-3
Soft-
ware
Flow
Cntl
Bit-2
Soft-
ware
Flow
Cntl
Bit-1
Soft-
ware
Flow
Cntl
Bit-0
LCR=0XBF
1 0 0 XON1 RD/WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
1 0 1 XON2 RD/WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
1 1 0 XOFF1 RD/WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
1 1 1 XOFF2 RD/WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
X X X FSTAT RD
RX-
RX-
RX-
RX-
TX-
TX- TX- TX- FSRS# pin is
RDYD# RDYC# RDYB# RDYA# _RDYD# RDYC# RDYB# RDYA# ^{a logic 0. No}
address lines
required.
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