Digital Elevator

[JasonJo]

hey guys im stumped on this project: make a 2 floor elevator. i am going to use an H-bridge to control which way the motor spins (ie. clockwise will make the elevator go up, counter - down).

anyway, here are the initial conditions to be met:
elevator must stop at both floors
elevator will only go up when it is down
elevator will only go down when it is up

any ideas to implement this? the class i am taking has no gone over microcontrollers, the farthest ive gone is MUX/DeMUX's.

PLEASE HELP!!!! [*(]

[Nice coder]

Please stop it with the please help bit.
I will help (i am nice coder after all)
put two reed switches on the track (one on each floor) and a magnet on the back of the car(the thingy which goes up and down), insetad of a h-bridge, just connect the power leads in differing polatities using the reed switches.

+ --_
sw1---_
sw2---------- lead 1
- --
- --_
sw1---_
sw2--------moveswitch-- lead 2
+ --

This should work, just don't mix up the two reed switches! (put them so that they engage only after they move to the floor)

Any questions so far?

[JasonJo]

how would it stop?

[Cliff_J]

Simple logic gates.

Write out the conditions using some sort of switch (like the reed or a simple contact switch) with a resistor to pull logic high/low. Then its simply "up switch AND elevator at floor 1 switch" stuff, and you could write out the truth tables to show your work.

Cliff