Rainbow Electronics W90N740 - Manual (Page 140)

W90N740
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7.8 USB Host Controller
The Universal Serial Bus (USB) is a low-cost, low-to-middle speed peripheral interface standard
intended for modem, printer, scanner, PDA, keyboard, mouse, and other devices that do not require a
high-bandwidth parallel interface. The USB is a 4-wire serial cable bus that supports serial data
exchange between a Host Controller and a peripheral device. The attached peripherals share USB
bandwidth through a host-scheduled, token-based protocol. Peripherals may be attached, configured,
used, and detached, while the host and other peripherals continue operation (i.e. hot plug and unplug
is supported).
It allows user to setup a flexible, plug-and-play networks of USB devices. And in the USB network,
there is only one USB host, but there can be many USB devices and USB hubs.
The Features of the USB Host Controller:
• USB 1.1 compatible
• Open Host Controller Interface (OHCI) 1.0 compatible.
• Supports both low-speed (1.5 Mbps) and full-speed (12Mbps) USB devices.
• Built-in DMA for real-time data transfer
• Option for on-chip USB transceiver or external USB transceiver