LPC2458 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2013. All rights reserved.
Product data sheet Rev. 4.1 — 15 October 2013 32 of 81
NXP Semiconductors
LPC2458
Single-chip 16-bit/32-bit micro
• Conforms to Multimedia Card Specification v2.11.
• Conforms to Secure Digital Memory Card Physical Layer Specification, v0.96.
• Can be used as a multimedia card bus or a secure digital memory card bus host. The
SD/MMC can be connected to several multimedia cards or a single secure digital
memory card.
• DMA supported through the GPDMA controller.
7.19 I
2
C-bus serial I/O controller
The LPC2458 contains three I
2
C-bus controllers.
The I
2
C-bus is bidirectional, 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 I
2
C-bus is a multi-master bus and can
be controlled by more than one bus master connected to it.
The I
2
C-bus implemented in LPC2458 supports bit rates up to 400 kbit/s (Fast I
2
C-bus).
7.19.1 Features
• I
2
C0 is a standard I
2
C compliant bus interface with open-drain pins.
• I
2
C1 and I
2
C2 use standard I/O pins and do not support powering off of individual
devices connected to the same bus lines.
• 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 I
2
C-bus can be used for test and diagnostic purposes.
7.20 I
2
S-bus serial I/O controllers
The I
2
S-bus provides a standard communication interface for digital audio applications.
The I
2
S-bus specification defines a 3-wire serial bus using one data line, one clock line,
and one word select signal. The basic I
2
S connection has one master, which is always the
master, and one slave. The I
2
S interface on the LPC2458 provides a separate transmit
and receive channel, each of which can operate as either a master or a slave.
