
W83627SF
PRELIMINARY
Publication Release Date: Nov. 2000
- 48 - Revision 0.60
TABLE 4-1 UART Register Bit Map
Bit Number
1
2
RX Data
Bit 1
Register Address Base
+ 0
BDLAB = 0
0
3
4
5
6
7
Receiver
Buffer
Register
(Read Only)
Transmitter
Buffer Register
(Write Only)
Interrupt Control
Register
RBR
RX Data
Bit 0
RX Data
Bit 2
RX Data
Bit 3
RX Data
Bit 4
RX Data
Bit 5
RX Data
Bit 6
RX Data
Bit 7
+ 0
BDLAB = 0
TBR
TX Data
Bit 0
TX Data
Bit 1
TX Data
Bit 2
TX Data
Bit 3
TX Data
Bit 4
TX Data
Bit 5
TX Data
Bit 6
TX Data
Bit 7
+ 1
BDLAB = 0
ICR
RBR Data
Ready
Interrupt
Enable
(ERDRI)
"0" if
Interrupt
Pending
TBR
Empty
Interrupt
Enable
(ETBREI)
Interrupt
Status
Bit (0)
USR
Interrupt
Enable
(EUSRI)
HSR
Interrupt
Enable
(EHSRI)
0
0
0
0
+ 2
Interrupt Status
Register
(Read Only)
ISR
Interrupt
Status
Bit (1)
Interrupt
Status
Bit (2)**
0
0
FIFOs
Enabled
**
RX
Interrupt
Active Level
(LSB)
Set
Silence
Enable
(SSE)
FIFOs
Enabled
**
RX
Interrupt
Active Level
(MSB)
Baudrate
Divisor
Latch
Access Bit
(BDLAB)
0
+ 2
UART FIFO
Control
Register
(Write Only)
UART Control
Register
UFR
FIFO
Enable
RCVR
FIFO
Reset
XMIT
FIFO
Reset
DMA
Mode
Select
Reserved
Reversed
+ 3
UCR
Data
Length
Select
Bit 0
(DLS0)
Data
Terminal
Ready
(DTR)
RBR Data
Ready
(RDR)
Data
Length
Select
Bit 1
(DLS1)
Request
to
Send
(RTS)
Overrun
Error
(OER)
Multiple
Stop Bits
Enable
(MSBE)
Parity
Bit
Enable
(PBE)
Even
Parity
Enable
(EPE)
Parity
Bit Fixed
Enable
PBFE)
+ 4
Handshake
Control
Register
HCR
Loopback
RI
Input
IRQ
Enable
Internal
Loopback
Enable
0
0
+ 5
UART Status
Register
USR
Parity Bit
Error
(PBER)
No Stop
Bit
Error
(NSER)
DCD
Toggling
(TDCD)
Bit 3
Silent
Byte
Detected
(SBD)
Clear
to Send
(CTS)
Bit 4
TBR
Empty
(TBRE)
TSR
Empty
(TSRE)
RX FIFO
Error
Indication
(RFEI) **
Data Carrier
Detect
(DCD)
+ 6
Handshake
Status Register
HSR
CTS
Toggling
(TCTS)
Bit 0
DSR
Toggling
(TDSR)
Bit 1
RI Falling
Edge
(FERI)
Bit 2
Data Set
Ready
(DSR)
Bit 5
Ring
Indicator
(RI)
Bit 6
+ 7
User Defined
Register
Baudrate
Divisor Latch
Low
Baudrate
Divisor Latch
High
UDR
Bit 7
+ 0
BDLAB = 1
BLL
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
+ 1
BDLAB = 1
BHL
Bit 8
Bit 9
Bit 10
Bit 11
Bit 12
Bit 13
Bit 14
Bit 15
*: Bit 0 is the least significant bit. The least significant bit is the first bit serially transmitted or received.
**: These bits are always 0 in 16450 Mode.