The USB interface is provided by a Philips ISP1761 controller that provides a standard USB host controller and an On-The-Go (OTG) dual role device controller. The USB host has two downstream ports. The OTG can function as either a host or slave device.
|Location||Baseboard (an ISP1761 chip)|
|Memory base address|
There are two DMA channels available for the USB controller. These are selectable as 0 or 1. See Single Master Direct Memory Access Controller, SMDMAC.
You must set DMAPSR =
|Release version||Custom interface to external controller|
|Reference documentation||ISP1761 Hi-Speed Universal Serial Bus On-The-Go controller Product data sheet. See also USB Interface, and the USB test program supplied on the CD.|
The ISP1761 has the following features:
fully compliant to the USB Rev. 2.0 specification
fully compliant to the USB On-The-Go specification
includes high-performance USB peripheral controller with integrated Serial Interface Engine, FIFO memory, and transceiver
configurable number of downstream and upstream hosts or functions
USB host is USB 2.0 compliant and supports 480Mb/s, 12Mb/s, and 1.5Mb/s
programmable interrupts and DMA
FIFO and 63KB on-chip RAM for USB.
The ISP1761 register base addresses are shown in Table 4.91.
|Host controller EHCI registers|
|Peripheral controller registers|
|Host controller configuration registers|
|OTG controller registers|
|Host controller buffer memory (63KB)|
The suspend/wakeup signals for the device and host controllers are connected to GPIO2 (see General Purpose Input/Output, GPIO).