Datasheet

Preliminary data sheet Rev. 00.01 — 23 October 2007 23 of 57

NXP Semiconductors

LPC2388

Fast communication chip

7.11 USB interface

The Universal Serial Bus (USB) is a 4-wire bus that supports communication between a

host and one or more (up to 127) peripherals. The Host Controller allocates the USB

bandwidth to attached devices through a token-based protocol. The bus supports hot

plugging and dynamic configuration of the devices. All transactions are initiated by the

Host Controller.

The LPC2388 USB interface includes a device, Host, and OTG Controller. Details on

typical USB interfacing solutions can be found in

Section 11.1.

7.11.1 USB device controller

The device controller enables 12 Mbit/s data exchange with a USB Host Controller. It

consists of a register interface, serial interface engine, endpoint buffer memory, and a

DMA controller. The serial interface engine decodes the USB data stream and writes data

to the appropriate endpoint buffer. The status of a completed USB transfer or error

condition is indicated via status registers. An interrupt is also generated if enabled. When

enabled, the DMA controller transfers data between the endpoint buffer and the USB

RAM.

7.11.1.1 Features

• Fully compliant with USB 2.0 specification (full speed).

• Supports 32 physical (16 logical) endpoints with a 4 kB endpoint buffer RAM.

• Supports Control, Bulk, Interrupt and Isochronous endpoints.

• Scalable realization of endpoints at run time.

• Endpoint Maximum packet size selection (up to USB maximum specification) by

software at run time.

• Supports SoftConnect and GoodLink features.

• While the USB is in the Suspend mode, the LPC2388 can enter one of the reduced

power modes and wake up on USB activity.

• Supports DMA transfers with the DMA RAM of 16 kB on all non-control endpoints.

• Allows dynamic switching between CPU-controlled and DMA modes.

• Double buffer implementation for Bulk and Isochronous endpoints.

7.11.2 USB Host Controller

The Host Controller enables full- and low-speed data exchange with USB devices

attached to the bus. It consists of register interface, serial interface engine and DMA

controller. The register interface complies with the OHCI specification.

7.11.2.1 Features

• OHCI compliant.

• Two downstream ports.

• Supports per-port power switching.