xr16l784iv Exar Corporation, xr16l784iv Datasheet - Page 25

• Manufacturer Part Number: xr16l784iv
• Description: High Performance 2.97v To 5.5v Quad Uart
• Manufacturer: Exar Corporation

xr
REV. 1.2.2
The first 8 registers are 16550 compatible with EXAR enhanced feature registers located on the upper 8
addresses. The 4 sets of UART configuration registers are decoded using address lines A0 to A3 as shown
below.
.
3.2
A3
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
A
A2
0
0
0
0
0
0
0
0
1
1
1
1
1
0
0
0
0
0
0
1
1
1
1
1
DDRESS
UART CHANNEL CONFIGURATION REGISTERS
A1
0
0
0
0
0
1
1
1
0
0
1
1
1
0
0
1
1
1
1
0
0
0
1
1
A0
0
0
0
1
1
0
0
1
0
1
0
0
1
0
1
0
0
1
1
0
0
1
0
1
RHR - Receive Holding Register
THR - Transmit Holding Register
DLL - Div Latch Low
DLM - Div Latch High
IER - Interrupt Enable Register
ISR - Interrupt Status Register
FCR - FIFO Control Register
LCR - Line Control Register
MCR - Modem Control Register
LSR - Line Status Register
MSR - Modem Status Register
RS485 Turn-Around Delay Register
SPR - Scratch Pad Register
FCTR - Feature Control Register
EFR - Enhanced Function Register
TXCNT - Transmit FIFO Level Counter
TXTRG - Transmit FIFO Trigger Level
RXCNT - Receive FIFO Level Counter
RXTRG - Receive FIFO Trigger Level
Xoff-1 - Xoff Character 1
Xchar
Xoff-2 - Xoff Character 2
Xon-1 - Xon Character 1
Xon-2 - Xon Character 2
T
ABLE
11: UART CHANNEL CONFIGURATION REGISTERS
R
EGISTER
16550 C
E
NHANCED
OMPATIBLE
25
R
HIGH PERFORMANCE 2.97V TO 5.5V QUAD UART
EGISTERS
R
EGISTERS
R
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read-only
Write-only
Read-only
Write-only
Read-only
Read-only
Write-only
Read-only
Write-only
Read-only
Write-only
Write-only
Read-only
Write-only
Write-only
Write-only
EAD
/W
RITE
Xon,Xoff Rcvd. Flags
LCR[7] = 0
LCR[7] = 0
LCR[7] = 1
LCR[7] = 1
LCR[7] = 0
C
OMMENTS
XR16L784