W81281

W81281 is a low cost, high integration single-chip microcontroller with Universal Serial Bus (USB) interface for keyboard application, it includes the core of Winbond 8-bit microprocessor W78C52 which works on 6MHz. It implements a standard PC keyboard and enables connection to host system through low-speed (1.5Mhz) USB connection . It complies with USB Specification Revision 1.0 and HID Class Definition Revision 1.0.

For Keyboard application, W81281 supports an 18 X 8 keyboard scan matrix, which allows suspend wake up, 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.

W81281 supports one device address and five endpoints, one bi-directional endpoint for Control transfer and four unidirectional endpoints for Interrupt IN transfer. Through modification of firmware of W78C52, it can be used for multifunction device design, such as USB-IR receiver and any Slow-Speed (1.5Mhz) USB peripheral device controller.