IPC@CHIP SC2x3
Hardware Manual V1.02 [01.03.09]
©2000-2009 BECK IPC GmbH
Page 31
6.2.4 USB
The SC2x3 supports two USB channels. The USB Controller implements the USB Host Controller/Root Hub in
compliance with the USB1.1 specification. The user may choose to have either one or two USB ports on the
root hub, each of which can interface to an off-chip USB transceiver. The Host Controller supports the Open
Host Controller Interface (OHCI) standard.
The interface has an integrated DMA controller that transfers packet data to and from memory. The DMA
controller facilitates USB endpoint data transfer efficiently, while limiting microprocessor involvement.
6.2.5 SPI
SPI is a high-speed synchronous serial input/output (I/O) port that allows a serial bit stream of programmed
length (one to eight bits) to be shifted into and out of the device at a programmable bit-transfer rate.
SPI is an industry-standard communications interface that does not have specifications or a standards
organizing group. As a result, there are no licensing requirements. Because of its simplicity, SPI is commonly
used in embedded systems. Many semiconductor manufacturers sell a variety of sensor, conversion, and
control devices that use SPI.
The SPI module allows full-duplex, synchronous, serial communication between the SC2x3 and peripheral
devices. The clock polarity, clock phase, SS (Slave Select) polarity, clock frequency in master mode, and the
number of bits to be transferred are software programmable up to 66MHz. SPI supports multiple slaves on a
single 3-wire bus by using separate Slave Select signals to enable the desired slave.