á
XR17C152
REV. 1.2.0
5V PCI BUS DUAL UART
33
TABLE 12: UART CHANNEL CONFIGURATION REGISTERS DESCRIPTION. SHADED BITS ARE ENABLED BY EFR BIT-4.
ADDRESS
A3-A0
REG
NAME
READ/
WRITE
BIT-7
BIT-6
BIT-5
BIT-4
BIT-3
BIT-2
BIT-1
BIT-0
COMMENT
0 0 0 0
RHR
R
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
LCR[7]=0
0 0 0 0
THR
W
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
LCR[7]=0
0 0 0 0
DLL
R/W
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
LCR[7]=1
0 0 0 1
DLM
R/W
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
LCR[7]=1
0 0 0 1
IER
R/W
0/
0
Modem
Status Int.
Enable
RX Line
Status Int.
Enable
TX Empty
Int.
Enable
RX Data
Int.
Enable
CTS/
DSR# Int.
Enable
RTS/
DTR# Int.
Enable
Xon/Xoff/
Sp. Char.
Int.
Enable
0 0 1 0
ISR
R
FIFOs
Enable
FIFOs
Enable
0/
INT
Source
Bit-3
INT
Source
Bit-2
INT
Source
Bit-1
INT
Source
Bit-0
Delta-
Flow Cntl
Xoff/spe-
cial char
0 0 1 0
FCR
W
RX FIFO
Trigger
RX FIFO
Trigger
0/
DMA
Mode
TX FIFO
Reset
RX FIFO
Reset
FIFOs
Enable
TX FIFO
Trigger
TX FIFO
Trigger
0 0 1 1
LCR
R/W
Divisor
Enable
Set TX
Break
Set Parity Even Par-
ity
Parity
Enable
Stop Bits
Word
Length
Bit-1
Word
Length
Bit-0
0 1 0 0
MCR
R/W
0/
Internal
Lopback
Enable
(OP2)1
(OP1)1
RTS# Pin
Control
DTR# Pin
Control
BRG
Prescaler
IR
Enable
XonAny
RTS/DTR
Flow Sel
0 1 0 1
LSR
R/W
RX FIFO
ERROR
TSR
Empty
THR
Empty
RX Break
RX Fram-
ing Error
RX Parity
Error
RX Over-
run
RX Data
Ready
0 1 1 0
MSR
R
CD
RI
DSR
CTS
Delta
CD#
Delta
RI#
Delta
DSR#
Delta
CTS#
MSR
W
RS485
DLY-3
RS485
DLY-2
RS485
DLY-1
RS485
DLY-0
Reserved Reserved Reserved Reserved
0 1 1 1
SPR
R/W
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
User Data
1 0 0 0
FCTR
R/W
TRG
Table
Bit-1
TRG
Table
Bit-0
Auto
RS485
Enable
Invert IR
RX Input
RTS/DTR
Hyst Bit-3
RTS/DTR
Hyst Bit-2
RTS/DTR
Hyst Bit-1
RTS/DTR
Hyst Bit-0
1 0 0 1
EFR
R/W
Auto
CTS/DSR
Enable
Auto
RTS/DTR
Enable
Special
Char
Select
Enable
IER [7:5],
ISR [5:4],
FCR[5:4],
MCR[7:5,2]
MSR[7:4]
Software
Flow Cntl
Bit-3
Software
Flow Cntl
Bit-2
Software
Flow Cntl
Bit-1
Software
Flow Cntl
Bit-0
1 0 1 0
TXCNT
R
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
1 0 1 0
TXTRG
W
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
1 0 1 1
RXCNT
R
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0
1 0 1 1
RXTRG
W
Bit-7
Bit-6
Bit-5
Bit-4
Bit-3
Bit-2
Bit-1
Bit-0