xr16m681 Exar Corporation, xr16m681 Datasheet - Page 23

• Manufacturer Part Number: xr16m681
• Description: 1.62v To 3.63v Uart With 32-byte Fifo And Vlio Interface
• Manufacturer: Exar Corporation

REV. 1.0.0
The complete register set for the M681 is shown in
3.0 UART INTERNAL REGISTERS
A
A2 A1 A0
DDRESSES
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0 0
0 1
0 0
0 1
1 0
0 1
1 0
1 1
0 0
0 1
1 0
1 0
1 1
1 1
1 1
0 0
0 0
0 1
1 0
0 0
0 1
1 0
1 1
0 0
DREV - Device Revision
DVID - Device Identification Register
DLL - Divisor LSB Register
DLM - Divisor MSB Register
DLD - Divisor Fractional Register
RHR - Receive Holding Register
THR - Transmit Holding Register
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
MSR - Modem Status Register
SPR - Scratch Pad Register
EMSR - Enhanced Mode Select Register
FC - RX/TX FIFO Level Counter Register
FC - RX/TX FIFO Level Counter Register
TRIG - RX/TX FIFO Trigger Level Register
FCTR - Feature Control Register
EFR - Enhanced Function Reg
Xon-1 - Xon Character 1
Xon-2 - Xon Character 2
Xoff-1 - Xoff Character 1
Xoff-2 - Xoff Character 2
T
ABLE
R
1.62V TO 3.63V UART WITH 32-BYTE FIFO AND VLIO INTERFACE
EGISTER
6: UART INTERNAL REGISTERS
16C550 C
E
NHANCED
OMPATIBLE
Table 6
23
R
EGISTERS
and
R
EGISTERS
Table
R
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read-only
Read-only
Read-only
Read-only
Read-only
Read-only
Read-only
Read-only
7.
Write-only
Write-only
Write-only
Write-only
Write-only
EAD
/W
RITE
LCR ≠ 0xBF if EFR[4] = 0
LCR ≠ 0xBF, FCTR[6] = 0
LCR ≠ 0xBF, FCTR[6] = 1
DLL = 0x00, DLM = 0x00
LCR[7] = 1, LCR ≠ 0xBF,
LCR[7] = 1, LCR ≠ 0xBF,
LCR[7] = 1, LCR ≠ 0xBF
LCR[7] = 0 if EFR[4] = 1
See DLD[7:6]
LCR = 0xBF
LCR ≠ 0xBF
LCR ≠ 0xBF
C
EFR[4] = 1
LCR[7] = 0
EFR[4] = 1
OMMENTS
XR16M681
or