Abstract: An apparatus for verifying the integrity of a printing system is provided. The apparatus includes an interpreter for converting an input image data file written in a first page description language into an output image data file written in a second page description language, and a comparator for comparing the output image data file with a reference output image data file.

Abstract: An electronically controlled programmable wall thermostat provides better control of comfort temperature and permits improved energy-saving temperature setback at selected intervals of the day or night in multistage heating and cooling systems and is particularly useful in achieving improved energy savings for systems having heat pump means in the main temperature conditioning stage of the system. The thermostat includes clock means, temperature sensing means, means for displaying desired parameters of time and temperature, data entry and storage means for programming the thermostat to maintain desired temperatures during selected time intervals, and a processing means with a memory incorporating a permanently stored program instruction sequence which responds to signals from the temperature sensing means for controlling the heating and cooling systems in accordance with the time-temperature sequence programmed into the thermostat by the user.