Engine analyzer with constant width digital waveform display

A test system for testing operation of a selected system or component of an internal combustion engine, the test system comprising:

• means for providing an analog input waveform representative of operation of the selected system or component of the internal combustion engine under a test condition, the analog input waveform having a period which varies as a function of engine speed;
• analog-to-digital (A/D) converter means for sampling the analog input waveform periodically at a date sample rate and converting each sample to a digital value;
• data memory means for storing the digital values;
• display means for displaying a simulated visual representation of the input waveform based upon the stored digital value, the simulated visual representation being representative of operation of the selected system or component of the internal combustion engine under the test condition;
• sample clock generator means for supplying an A/D clock signal to the A/D converter means which determines the data sample rate of the A/D converter means;
• means for supplying a signal to the A/D converter means to initiate sampling of the analog input waveform by the A/D converter means;
• and
• means for transferring a predetermined number of digital values representative of the input waveform from the A/D converter means to selected locations in the data memory means.

A test system for testing operation of a selected system or component of an internal combustion engine, the test system comprising:

• means for providing a periodic analog input waveform representative of operation of the selected system or component of the internal combustion engine under a test condition, the periodic analog input waveform having a period which varies as a function of engine speed;
• analog-to-digital (A/D) converter means for sampling the analog input waveform periodically at a data sample rate in response to an A/D clock signal and converting each sample to a digital value;
• period measuring means for measuring the period of the input waveform prior to sampling of the input waveform;
• sample clock generator means for supplying the A/D clock signal to the A/D converter means as a function of the measured period;
• data memory means for storing a predetermined number of digital values from the A/D converter means;
• and
• display means for displaying a simulated visual representative of the input waveform based upon the stored predetermined number of digital values, the simulated visual representation being representative of operation of the selected system or component of the internal combustion engine under the test condition.

A test system for testing operation of a selected system or component of an internal combustion engine, the test system comprising:

• means for providing an analog input waveform representative of operation of the selected system or component of the internal combustion engine under a test condition, the analog input waveform being a period which varies as a function of engine speed;
• analog-to-digital (A/D) converter means for sampling the analog input waveform periodically at a data sample rate in response to an A/D clock signal and converting each sample to a digital value;
• data memory means for storing the digital values from the A/D converter means;
• display means for displaying a simulated visual representation of the input waveform based upon the stored digital values, the simulated visual representation being representative of operation of the selected system or component of the internal combustion engine under the test condition;
• period measuring means for measuring the period of the input waveform prior to sampling of the input waveform by the A/D converter means;
• means for supplying the A/D clock signal to the A/D converter means as a function of the measured period;
• means for supplying a signal to the A/D converter means to initiate sampling of the analog input waveform by the A/D converter means;
• and
• means for transferring a predetermined number of digital values representative of the input waveform from the A/D converter means to selected locations in the data memory means.