xr16c2550ip Exar Corporation, xr16c2550ip Datasheet - Page 15

• Manufacturer Part Number: xr16c2550ip
• Description: Dual Uart With 16-byte Transmit And Receive Fifos
• Manufacturer: Exar Corporation

xr
REV. 1.0.1
Each of the UART channel in the 2550 has its own set of configuration registers selected by address lines A0,
A1 and A2 with CSA# or CSB# selecting the channel. The registers are 16C550 compatible. The complete
register set is shown on
3.0 UART INTERNAL REGISTERS
A2,A1,A0 A
0
0
0
0
0
1
1
1
1
0
0 0
0 1
0 1
1 0
1 1
0 0
0 1
1 0
1 1
0 0
DDRESSES
T
ABLE
Table 6
RHR - Receive Holding Register
THR - Transmit Holding Register
DLL - Div Latch Low Byte
DLM - Div Latch High Byte
IER - Interrupt Enable Register
ISR - Interrupt Status Register
FCR - FIFO Control Register
LCR - Line Control Register
MCR - Modem Control Register
LSR - Line Status Register
Reserved
MSR - Modem Status Register
Reserved
SPR - Scratch Pad Register
6: UART CHANNEL A AND B UART INTERNAL REGISTERS
and
Table
16C550 C
R
EGISTER
7.
OMPATIBLE
15
R
EGISTERS
2.97V TO 5.5V DUART WITH 16-BYTE FIFO
R
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read-only
Read-only
Read-only
Read-only
Write-only
Write-only
Write-only
Write-only
EAD
/W
RITE
LCR[7] = 0
LCR[7] = 1
LCR[7] = 1
LCR[7] = 0
C
OMMENTS
XR16C2550