Abstract: A computerized emissions tester determines concentrations of HC, CO, and CO2 in exhaust emissions. An IR test bench assembly develops an analog voltage representative of the concentration of a particular gas in a sample gas of known concentration. Data related to calibration pressure, voltage offset and voltage gain are stored in non-volatile memory EEPROM. Algorithms relating voltage and concentration of the particular gases are included in software. The pressure of an exhaust emission is compared with the calibration pressure data in memory and a correction is applied to the tester output. The data relating to the voltage offset and gain factor are also used to compensate the tester output.

Abstract: The plural source arbitration system relates generally to communications systems for linking peripheral devices to a computer. Specifically, the arbitration system allows an external keyboard and a remote control device to be intercoupled to the keyboard slot of a computer and carry out communications without confusion.