UM10429
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© NXP B.V. 2010. All rights reserved.
User manual
Rev. 1 — 20 October 2010
69 of 258
10.1 How to read this chapter
The UART block is implemented on the LPC1101 without modem control.
10.2 Basic configuration
The UART is configured using the following registers:
1. Pins: The UART pins must be configured in the IOCONFIG register block
(
) before the UART clocks can be enabled.
2. Power: In the SYSAHBCLKCTRL register, set bit 12 (
3. Peripheral clock: Enable the UART peripheral clock by writing to the UARTCLKDIV
register (
10.3 Features
•
16-byte receive and transmit FIFOs.
•
Register locations conform to ‘550 industry standard.
•
Receiver FIFO trigger points at 1, 4, 8, and 14 bytes.
•
Built-in baud rate generator.
•
UART allows for implementation of either software or hardware flow control.
•
RS-485/EIA-485 9-bit mode support with output enable.
10.4 Pin description
10.5 Register description
The UART contains registers organized as shown in
. The Divisor Latch Access
Bit (DLAB) is contained in U0LCR[7] and enables access to the Divisor Latches.
UM10429
Chapter 10: LPC1102 Universal Asynchronous Transmitter
(UART)
Rev. 1 — 20 October 2010
User manual
Table 70.
UART pin description
Pin
Type
Description
RXD
Input
Serial Input.
Serial receive data.
TXD
Output
Serial Output.
Serial transmit data.