XR19L220_07 Datasheet, PDF (19/43 Pages) Exar Corporation – SINGLE CHANNEL INTEGRATED UART AND RS-232 TRANSCEIVER

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XR19L220
SINGLE CHANNEL INTEGRATED UART AND RS-232 TRANSCEIVER
TABLE 6: 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
16C550 Compatible Registers
0 0 0 RHR RD Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
0 0 0 THR WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
001
IER RD/WR 0/
0/
0/
0/
Modem RX Line TX
RX
Stat. Int. Stat. Empty Data ^LCR[7]=0
CTS Int. RTS Int. Xoff Int. Sleep _{Enable Int.}
Int
Int.
Enable Enable Enable Mode
Enable Enable Enable
Enable
010
010
ISR
FCR
RD FIFOs FIFOs
0/
0/
INT
INT INT INT
Enabled Enabled
INT
INT
Source Source
Source Source Source Source
Bit-3 Bit-2 Bit-1 Bit-0
Bit-5 Bit-4
LCR ≠ 0xBF
WR RXFIFO RXFIFO 0/
0/
DMA
TX
RX FIFOs
Trigger
Trigger
TXFIFO TXFIFO
Trigger Trigger
Mode
Enable
FIFO FIFO Enable
Reset Reset
011
LCR RD/WR Divisor Set TX Set Par- Even
Enable Break
ity
Parity
Parity
Enable
Stop
Bits
Word Word
Length Length
Bit-1 Bit-0
100
101
110
111
000
001
000
001
MCR RD/WR 0/
BRG
Pres-
caler
0
0/ Internal INT Out- (OP1#) RTS DTR#
Loop-
put
XonAny _{back Enable}
Output Output
Control Control
Enable _(OP2#)
LSR RD RX FIFO THR & THR
RX RX Fram- RX
RX
RX _{LCR ≠ 0xBF}
Global TSR Empty Break ing Error Parity Over- Data
Error Empty
Error run Ready
Error
MSR
RD CD Input RI Input DSR
Input
CTS Delta CD Delta Delta Delta
Input
RI DSR CTS
SPR RD/WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0 LCR ≠ 0xBF
DLL RD/WR Bit-7
Baud Rate Generator Divisor
Bit-6 Bit-5 Bit-4
Bit-3
Bit-2 Bit-1 Bit-0 ^LCR[7]=1
DLM RD/WR Bit-7 Bit-6 Bit-5 Bit-4
Bit-3 Bit-2 Bit-1 Bit-0
DREV RD
DVID RD
Bit-7
0
Bit-6
0
Bit-5
0
Bit-4
0
Bit-3
0
Bit-2
0
Bit-1
0
Bit-0
1
LCR[7]=1
DLL=0x00
DLM=0x00
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