W712 Datasheet, PDF (10/17 Pages) OKI electronic componets – Universal Serial Bus Controller 0.5uM Technology Mega Macrofunction

s W712 USB Device Controller s –––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Application Interface
The Application Interface uses an i486-like bus to interface between the customer’s module and the W712.
By using an i486-like bus protocol, the W712 can be easily integrated into any customer-designed module.
The integration is limited only by the available gates and I/O pins in the array. The Customer Application
Module may have its own external I/O, which do not interface with the W712. All application interface
signals are unidirectional, and are either inputs or outputs of the W712.
Frame Timer Synthesizer
This block synthesizes the SOF signal in the event of a SOF token is lost.
Remote Wakeup
This block provides support for the remote wakeup function.
USB Transfers
The W712 supports all four transfer types defined by the USB specification. These are: Control, Isochro-
nous, Interrupt, and Bulk.
• Control transfers must be supported by every peripheral for configuration, command and status
information flow between the host and peripheral.
• Isochronous transfers provide guaranteed bus access and constant data rates for USB devices.
• Interrupt transfers support human input devices that need to communicate small amounts of data
infrequently.
• Bulk transfers enable devices to transfer large amounts of data as bus bandwidth becomes available.
USB Interface
The W712 connects to the Universal Serial Bus via Oki’s universal USB transceivers. The USB specific I/O
converts the W712’s internal unidirectional signals into compliant USB signals. The universal USB trans-
ceiver allows the designers’ application module to interface with the physical layer of the Universal Serial
Bus. It transmits and receives serial data at both full-speed (12Mb/s) and low-speed (1.5Mb/s) data rates.
See Appendix for Oki’s USB transceiver Data Sheets.
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Oki Semiconductor