XR17D158_05 Datasheet, PDF (39/73 Pages) Exar Corporation – UNIVERSAL (3.3V AND 5V) PCI BUS OCTAL UART

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REV. 1.2.2
XR17D158
UNIVERSAL (3.3V AND 5V) PCI BUS OCTAL UART
TABLE 12: UART CHANNEL CONFIGURATION REGISTERS
ADDRESS
REGISTER
READ/WRITE
COMMENTS
1 0 1 0 TXTRG - Transmit FIFO Trigger Level
Write-only
1 0 1 1 RXCNT - Receive FIFO Level Counter
Read-only
1 0 1 1 RXTRG - Receive FIFO Trigger Level
Write-only
1 1 0 0 Xoff-1 - Xoff Character 1
Write-only
1 1 0 0 Xchar
Read-only
Xon,Xoff Rcvd. Flags
1 1 0 1 Xoff-2 - Xoff Character 2
Write-only
1 1 1 0 Xon-1 - Xon Character 1
Write-only
1 1 1 1 Xon-2 - Xon Character 2
Write-only
TABLE 13: 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
0000
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
0001
IER
R/W
0/
0/
0/
CTS/
DSR# Int.
Enable
RTS/
DTR# Int.
Enable
Xon/Xoff/
Sp. Char.
Int.
Enable
0
Modem RX Line TX Empty RX Data
Status Int. Status Int. Int.
Int.
Enable Enable Enable Enable
0010
ISR
R
FIFOs FIFOs
0/
0/
INT
INT
INT
INT
Enable
Enable
Source
Delta- Xoff/special _Bit-3
Flow Cntl char
Source
Bit-2
Source
Bit-1
Source
Bit-0
0 0 1 0 FCR
W RX FIFO RX FIFO
0/
0/
DMA TX FIFO RX FIFO FIFOs
Trigger Trigger
TX FIFO TX FIFO
Mode
Reset
Reset Enable
Trigger Trigger
0011
LCR
R/W Divisor Set TX Set Parity Even Par- Parity Stop Bits Word
Word
Enable Break
ity
Enable
Length Length
Bit-1
Bit-0
0100
MCR
R/W
0/
0/
0/
Internal
Lopback
BRG
IR
XonAny Enable
Prescaler _Enable
(OP2)¹
(OP1)¹
RTS/DTR
Flow Sel
RTS# Pin
Control
DTR# Pin
Control
0101
LSR
R/W RX FIFO TSR
ERROR Empty
THR RX Break RX Fram- RX Parity RX Over- RX Data
Empty
ing Error Error
run
Ready
0 1 1 0 MSR
R
CD
RI
DSR
CTS
Delta
Delta
Delta
Delta
CD#
RI#
DSR# CTS#
MSR
W
RS485 RS485 RS485 RS485 Reserved Reserved Reserved Reserved
DLY-3 DLY-2 DLY-1
DLY-0
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