High Country Tek emc-3L - Manual (Page 103)

16 Appendix F Flowchart (Sequence of Operations) example
This example will demonstrate how to create a flowchart and Sequence of Operations. This example may or
may not work; it is for educational purposes only.
Programming
Team:
Paul – Programmer, Electrical Engineer
Mark – Program Manager
Amanda – Application Engineer
Todd – Hydraulics Engineer
Date:
6/4/08
Program
Description:
Using the HCT DVC family, control steering and propulsion functions of a new skidsteer model
Using a J1939 equipped diesel engine.
Functional
Description:
The operator has control over one joystick. Critical functions are the engine rpm > 1000rpm and high
side pressure is below 2000psi, then the system looks for input from the joystick as indicated below.
Joystick has 5 positions
Joystick forward – skidsteer moves forward motion
Joystick back – skidsteer moves in reverse motion
Joystick right – skidsteer turns right
Joystick left – skidsteer turns left
Joystick center – skidsteer stops in present position
I/O needed
Inputs Joystick forward digital input 1, active high
Joystick back digital input 2, active high
Joystick right digital input 3, active high
Joystick left digital input 4, active high
Joystick center digital input 5, active high
Left wheels, high side press. Trans 0-3000psi transducer, 0-5v, 0-100% input
Right wheels, high side press. Trans 0-3000psi transducer, 0-5v, 0-100% input
Engine load J1939 signal
Engine rpm J1939 signal
Outputs
Left wheels pump forward control pwm Min cur 0.2a, Max cur 0.9a
Left wheels pump reverse control pwm Min cur 0.2a, Max cur 0.9a
Right wheels pump forward control pwm Min cur 0.2a, Max cur 0.9a
Right wheels pump reverse control pwm Min cur 0.2a, Max cur 0.9a
Turning left indicator, bang bang out LED indicator along with standard relay
Turning right indicator, bang bang out LED indicator along with standard relay
Step #1 Assure engine rpm is above 1000rpm
Assure high pressure, left wheel system < 2000psi
Assure high pressure, right wheel system < 2000psi
P/N: 021-00163, Rev. A.0 - for V5.2 Tools Page | 103