Hardware-based graphics interface for medical device sensors and controllers

Abstract

A completely hardware-based graphics interface controller for reading values from sensors or outputting voltages, currents, or other electrical parameters to medical devices is proposed. The graphics interface controller accepts analog or digital input into a programmable logic device (PLD), whose logic gates convert the input value to memory addresses of bitmaps that represent digits or other characters. The bitmaps are copied to respective x, y coordinates in a frame buffer, which are then displayed on a matrix liquid crystal display (LCD) panel. The bitmaps can be simple or elaborate, mimicking the rich look and feel of general purpose computer fonts so that the display output is compelling and modern-looking despite being entirely hardware based. A ventilator or other medical device can be instrumented with one or more sensors whose outputs are to the graphics interface, and an alarm can be triggered for off-nominal conditions.