UM10429
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© NXP B.V. 2010. All rights reserved.
User manual
Rev. 1 — 20 October 2010
70 of 258
NXP Semiconductors
UM10429
Chapter 10: LPC1102 Universal Asynchronous Transmitter (UART)
[1]
Reset Value reflects the data stored in used bits only. It does not include reserved bits content.
Table 71.
Register overview: UART (base address: 0x4000 8000)
Name
Access Address
offset
Description
Reset
value
U0RBR
RO
0x000
Receiver Buffer Register. Contains the next received character to be read.
(DLAB=0)
NA
U0THR
WO
0x000
Transmit Holding Register. The next character to be transmitted is written
here. (DLAB=0)
NA
U0DLL
R/W
0x000
Divisor Latch LSB. Least significant byte of the baud rate divisor value. The
full divisor is used to generate a baud rate from the fractional rate divider.
(DLAB=1)
0x01
U0DLM
R/W
0x004
Divisor Latch MSB. Most significant byte of the baud rate divisor value. The
full divisor is used to generate a baud rate from the fractional rate divider.
(DLAB=1)
0x00
U0IER
R/W
0x004
Interrupt Enable Register. Contains individual interrupt enable bits for the 7
potential UART interrupts. (DLAB=0)
0x00
U0IIR
RO
0x008
Interrupt ID Register. Identifies which interrupt(s) are pending.
0x01
U0FCR
WO
0x008
FIFO Control Register. Controls UART FIFO usage and modes.
0x00
U0LCR
R/W
0x00C
Line Control Register. Contains controls for frame formatting and break
generation.
0x00
-
-
0x010
Reserved -
U0LSR
RO
0x014
Line Status Register. Contains flags for transmit and receive status,
including line errors.
0x60
-
-
0x018
Reserved -
U0SCR
R/W
0x01C
Scratch Pad Register. Eight-bit temporary storage for software.
0x00
U0ACR
R/W
0x020
Auto-baud Control Register. Contains controls for the auto-baud feature.
0x00
-
-
0x024
Reserved -
U0FDR
R/W
0x028
Fractional Divider Register. Generates a clock input for the baud rate
divider.
0x10
-
-
0x02C
Reserved
-
U0TER
R/W
0x030
Transmit Enable Register. Turns off UART transmitter for use with software
flow control.
0x80
-
-
0x034 -
0x048
Reserved
-
U0RS485CTRL R/W
0x04C
RS-485/EIA-485 Control. Contains controls to configure various aspects of
RS-485/EIA-485 modes.
0x00
U0ADRMATCH R/W
0x050
RS-485/EIA-485 address match. Contains the address match value for
RS-485/EIA-485 mode.
0x00