xr16m680 Exar Corporation, xr16m680 Datasheet - Page 27

• Manufacturer Part Number: xr16m680
• Description: 1.62v To 3.63v High Performance Uart With 32-byte Fifo
• Manufacturer: Exar Corporation

REV. 1.0.0
SEE”RECEIVER” ON PAGE 16.
SEE”TRANSMITTER” ON PAGE 15.
The Interrupt Enable Register (IER) masks the interrupts from receive data ready, transmit empty, line status
and modem status registers. These interrupts are reported in the Interrupt Status Register (ISR).
4.0 INTERNAL REGISTER DESCRIPTIONS
4.1
4.2
4.3
A
A2-A0
DDRESS
0 1 0
0 0 0
0 0 1
0 0 0
0 0 1
0 0 0
0 0 1
0 1 0
1 0 0
1 0 1
1 1 0
1 1 1
T
Receive Holding Register (RHR) - Read- Only
Transmit Holding Register (THR) - Write-Only
Interrupt Enable Register (IER) - Read/Write
ABLE
XOFF1 RD/WR
XOFF2 RD/WR
DREV
FCTR RD/WR
XON1 RD/WR
XON2 RD/WR
N
DVID
DLM
DLD
EFR
R
DLL
FC
AME
EG
7: INTERNAL REGISTERS DESCRIPTION.
RD/WR
RD/WR
RD/WR
RD/WR
R
W
RD
RD
RD
EAD
RITE
/
Enable
RX/TX
select
select
CTS#
B
BRG
Bit-7
Bit-7
Bit-7
Bit-7
Auto
Bit-7
Bit-7
Bit-7
Bit-7
IT
0
-7
Indepen-
Enable
Enable
RTS#
Swap
B
BRG
SCR
Bit-6
Bit-6
Bit-6
Bit-6
Auto
Bit-6
Bit-6
Bit-6
Bit-6
dent
IT
1.62V TO 3.63V HIGH PERFORMANCE UART WITH 32-BYTE FIFO
0
-6
Baud Rate Generator Divisor
4X Mode 8X Mode
Enhanced Registers
Special
Select
B
Char
Bit-5
Bit-5
Bit-5
Bit-5
Bit-5
Bit-5
Bit-5
Bit-5
IT
0
0
-5
27
MCR[7:5],
FCR[5:3],
IER [7:4],
ISR [5:4],
Enable
B
Bit-4
Bit-4
Bit-4
Bit-4
DLD
Bit-4
Bit-4
Bit-4
Bit-4
IT
0
0
-4
S
HADED BITS ARE ENABLED WHEN
interrupt
RS485
mode
B
Soft-
ware
Flow
Bit-3
Bit-3
Bit-3
Bit-3
Bit-3
Bit-3
Bit-3
Bit-3
Bit-3
Bit-3
Cntl
IT
0
-3
RX IR
invert
B
ware
Flow
Bit-2
Bit-2
Bit-2
Bit-2
Bit-2
Soft-
Bit-2
Bit-2
Bit-2
Bit-2
Bit-2
Cntl
IT
1
-2
B
ware
Flow
Bit-1
Bit-1
Bit-1
Bit-1
Bit-1
Soft-
Bit-1
Bit-1
Bit-1
Bit-1
Bit-1
Cntl
IT
0
0
-1
EFR B
B
ware
Flow
Bit-0
Bit-0
Bit-0
Bit-0
Bit-0
Soft-
Bit-0
Bit-0
Bit-0
Bit-0
Bit-0
Cntl
IT
1
0
XR16M680
-0
IT
-4=1
DLM= 0x00
LCR[7] = 1
LCR≠0xBF
DLL= 0x00
LCR[7] = 1
LCR≠0xBF
LCR[7] = 1
LCR≠0xBF
EFR[4] = 1
LCR=0
C
DLD[7:6]
OMMENT
X
BF