
DR
AFT
DR
AFT
DRAFT
DR
D
RAFT
DRAFT
DRA
FT DRAF
D
RAFT DRAFT DRAFT DRAFT DRAFT D
DRAFT
D
RAFT DRA
FT DRAFT DRAFT DRAFT DRA
UM10360_0
© NXP B.V. 2009. All rights reserved.
User manual
Rev. 00.06 — 5 June 2009
274 of 808
NXP Semiconductors
UM10360
Chapter 14: LPC17xx UART0/2/3
UnLCR must be one in order to access the UARTn Divisor Latches. Details on how to
select the right value for U1DLL and U1DLM can be found later in this chapter, see
.
4.4 UARTn Interrupt Enable Register (U0IER - 0x4000 C004, U2IER -
0x4009 8004, U3IER - 0x4009 C004 when DLAB = 0)
The UnIER is used to enable the three UARTn interrupt sources.
Table 251: UARTn Divisor Latch LSB register (U0DLL - address 0x4000 C000,
U2DLL - 0x4009 8000, U3DLL - 0x4009 C000 when DLAB = 1) bit description
Bit
Symbol
Description
Reset Value
7:0
DLLSB
The UARTn Divisor Latch LSB Register, along with the UnDLM
register, determines the baud rate of the UARTn.
0x01
Table 252: UARTn Divisor Latch MSB register (U0DLM - address 0x4000 C004,
U2DLM - 0x4009 8004, U3DLM - 0x4009 C004 when DLAB = 1) bit description
Bit
Symbol
Description
Reset Value
7:0
DLMSB
The UARTn Divisor Latch MSB Register, along with the U0DLL
register, determines the baud rate of the UARTn.
0x00
Table 253: UARTn Interrupt Enable Register (U0IER - address 0x4000 C004,
U2IER - 0x4009 8004, U3IER - 0x4009 C004 when DLAB = 0) bit description
Bit
Symbol
Value
Description
Reset
Value
0
RBR
Interrupt
Enable
Enables the Receive Data Available interrupt for UARTn. It
also controls the Character Receive Time-out interrupt.
0
0
Disable the RDA interrupts.
1
Enable the RDA interrupts.
1
THRE
Interrupt
Enable
Enables the THRE interrupt for UARTn. The status of this
can be read from UnLSR[5].
0
0
Disable the THRE interrupts.
1
Enable the THRE interrupts.
2
RX Line
Status
Interrupt
Enable
Enables the UARTn RX line status interrupts. The status of
this interrupt can be read from UnLSR[4:1].
0
0
Disable the RX line status interrupts.
1
Enable the RX line status interrupts.
7:3
-
Reserved, user software should not write ones to reserved
bits. The value read from a reserved bit is not defined.
NA
8
ABEOIntEn
Enables the end of auto-baud interrupt.
0
0
Disable end of auto-baud Interrupt.
1
Enable end of auto-baud Interrupt.
9
ABTOIntEn
Enables the auto-baud time-out interrupt.
0
0
Disable auto-baud time-out Interrupt.
1
Enable auto-baud time-out Interrupt.
31:10 -
Reserved, user software should not write ones to reserved
bits. The value read from a reserved bit is not defined.
NA