W81C280

W81C280 is a single-chip microcontroller with Universal Serial Bus (USB) interface for keyboard application, it includes the core of Winbond's 8-bit microprocessor W78C52. It implements a standard PC keyboard and enables connection to host system through low- speed (1.5Mhz) or high speed(12Mhz) . It complies with USB Specification Revision 1.0 and HID Class Definition Revision 1.0.

W81C280 supports an 18 X 8 keyboard scan matrix wihich allows suspend wakeup, and also provides a port for PS/2 mouse. It consists of an 8051 compatible CPU core, a 6K-byte ROM, a 256-byte SRAM, and three 16-bit programmable timers.

W81C280 supports one device address and five endpoints, one for Control transfer and four for Interrupt transfer. Through modification of firmware of W78C52, it can be used for multi-function device design, such as USB-IR receiver and any High-Speed(12Mhz)/Slow-Speed(1.5Mhz) USB peripheral device controller.