Rainbow Electronics NUC140 - Manual (Page 50)

NUC140 Series DATA SHEET
Publication Release Date: May 31, 2010
- 50 - Revision V1.02
5.14 PS2 Device Controller (PS2D)
5.14.1 Overview
PS/2 device controller provides basic timing control for PS/2 communication. All communication
between the device and the host is managed through the CLK and DATA pins. Unlike PS/2 keyboard
or mouse device controller, the received/transmit code needs to be translated as meaningful code by
firmware. The device controller generates the CLK signal after receiving a request to send, but host
has ultimate control over communication. DATA sent from the host to the device is read on the rising
edge and DATA sent from device to the host is change after rising edge. A 16 bytes FIFO is used to
reduce CPU intervention. S/w can select 1 to 16 bytes for a continuous transmission.
5.14.2 Features
y APB interface compatible
y Host communication inhibit and request to send detection
y Reception frame error detection
y Programmable 1 to 16 bytes transmit buffer to reduce CPU intervention
y Double buffer for data reception
y S/W override bus