Appendix D  On-screen Controls 
D - 28  Instructions for Use 
M-Mode Measurement Tools 
Selection  Description 
Distance 
Distance 
Calculates the length of a vertical line. 
Heart Rate 
Heart Rate 
Defines the number of heart cycles between two delimiters. 
Acceleration 
Slope 
Measures the change in distance over time. 
Time 
Time 
Measures time on an M-mode sweep.