NXP Semiconductors
LPC2109/2119/2129
Single-chip 16/32-bit microcontrollers
• UART1 is equipped with standard modem interface signals. This module also
provides full support for hardware flow control (auto-CTS/RTS).
6.10.2 UART features available in LPC2109/2119/2129/01 only
Compared to previous LPC2000 microcontrollers, UARTs in LPC2109/2119/2129/01
introduce a fractional baud rate generator for both UARTs, enabling these microcontrollers
to achieve standard baud rates such as 115200 Bd with any crystal frequency above
2 MHz. In addition, auto-CTS/RTS flow-control functions are fully implemented in
hardware.
• Fractional baud rate generator enables standard baud rates such as 115200 Bd to be
achieved with any crystal frequency above 2 MHz.
• Auto-bauding.
• Auto-CTS/RTS flow-control fully implemented in hardware.
6.11 I2C-bus serial I/O controller
The I2C-bus is a bidirectional bus for inter-IC control using only two wires: a serial clock
line (SCL), and a serial data line (SDA). Each device is recognized by a unique address
and can operate as either a receiver-only device (e.g. an LCD driver or a transmitter with
the capability to both receive and send information (such as memory). Transmitters and/or
receivers can operate in either master or slave mode, depending on whether the chip has
to initiate a data transfer or is only addressed. The I2C-bus is a multi-master bus; it can be
controlled by more than one bus master connected to it.
The I2C-bus implemented in LPC2109/2119/2129 supports a bit rate up to 400 kbit/s (Fast
I2C-bus).
6.11.1 Features
• Standard I2C-bus compliant interface.
• Easy to configure as Master, Slave, or Master/Slave.
• Programmable clocks allow versatile rate control.
• Bidirectional data transfer between masters and slaves.
• Multi-master bus (no central master).
• Arbitration between simultaneously transmitting masters without corruption of serial
data on the bus.
• Serial clock synchronization allows devices with different bit rates to communicate via
one serial bus.
• Serial clock synchronization can be used as a handshake mechanism to suspend and
resume serial transfer.
• The I2C-bus may be used for test and diagnostic purposes.
LPC2109_2119_2129_6
Product data sheet
Rev. 06 — 10 December 2007
© NXP B.V. 2007. All rights reserved.
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