SMSC DS – LPC47M14X
Page 70
Rev. 03/19/2001
REGISTER
ADDRESS*
REGISTER NAME
REGISTER
SYMBOL
BIT 0
BIT 1
ADDR = 6
MODEM Status Register
MSR
Delta Clear
to Send
(DCTS)
Delta Data
Set Ready
(DDSR)
ADDR = 7
Scratch Register (Note 4)
SCR
Bit 0
Bit 1
ADDR = 0
DLAB = 1
Divisor Latch (LS)
DDL
Bit 0
Bit 1
ADDR = 1
DLAB = 1
Divisor Latch (MS)
DLM
Bit 8
Bit 9
*DLAB is Bit 7 of the Line Control Register (ADDR = 3).
Note 1:
Bit 0 is the least significant bit. It is the first bit serially transmitted or received.
Note 2:
When operating in the XT mode, this bit will be set any time that the transmitter shift register is empty.
Table 33 – Register Summary for an Individual UART Channel (continued)
BIT 2
BIT 3
BIT 4
BIT 5
BIT 6
BIT 7
Data Bit 2
Data Bit 3
Data Bit 4
Data Bit 5
Data Bit 6
Data Bit 7
Data Bit 2
Data Bit 3
Data Bit 4
Data Bit 5
Data Bit 6
Data Bit 7
0
Enable
Receiver Line
Status
Interrupt
(ELSI)
Enable
MODEM
Status
Interrupt
(EMSI)
0
0
0
Interrupt ID Bit Interrupt ID Bit
(Note 5)
0
0
FIFOs
Enabled
(Note 5)
FIFOs
Enabled
(Note 5)
XMIT
Reset
FIFO
DMA
Select (Note
6)
Mode
Reserved
Reserved
RCVR Trigger
LSB
RCVR Trigger
MSB
Number
Stop
(STB)
of
Bits
Parity Enable
(PEN)
Even
Select (EPS)
Parity
Stick Parity
Set Break
Divisor Latch
Access
(DLAB)
Bit
OUT1
(Note 3)
OUT2
(Note 3)
Loop
0
0
0
Parity
(PE)
Error
Framing Error
(FE)
Break
Interrupt (BI)
Transmitter
Holding
Register
(THRE)
Transmitter
Empty (TEMT)
(Note 2)
Error in RCVR
FIFO (Note 5)
Trailing Edge
Ring Indicator
(TERI)
Bit 2
Delta
Carrier Detect
(DDCD)
Data
Clear to Send
(CTS)
Data
Ready (DSR)
Set
Ring Indicator
(RI)
Data
Detect (DCD)
Carrier
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 10
Bit 11
Bit 12
Bit 13
Bit 14
Bit 15
Note 3:
This bit no longer has a pin associated with it.
Note 4:
When operating in the XT mode, this register is not available.
Note 5:
These bits are always zero in the non-FIFO mode.
Note 6:
Writing a one to this bit has no effect. DMA modes are not supported in this chip.
Note 7:
The UART1 and UART2 FCR’s are shadowed in the UART1 FIFO Control Shadow Register (runtime
register at offset 0x20) and UART2 FIFO Control Shadow Register (runtime register at offset 0x21).