LabVIEW
Beginner question re: case structures
Solved!
You need to attach the type definition. Also try to avoid overlapping wires because it can leat to errors that are hard to detect.
- Obviously, you need to remain in the take money state until there is enough money.
- Similarly, you need to stay in the dispense state until an item has been dispensed.
- you don't need the select node in the "give change" state, the change will be zero if the entered amount is correct.
- the "select soda" led belongs outside the case structure.
- Implement the power off state that returns change in any is left before shutting down.
- It never stays more than 100ms in the waiting state because it will alway continue to the take money state. Isn't that what you want? (taking money until there is enough and waiting seems to be the same thing, more or less.)
- etc. ...
@gsrokmix wrote:wouldn't I still need the code to calculate & dispense the change?
Yes, but the amount is automatically zero of the amount is correct. Only the subtraction is important, the select node is no needed.
gsrokmix wrote:What is the difference if the select soda LED stays in or out of the case structure? Is it causing something I don't want while remaining inside?
If you stay in the add money state until there is enough money, the LED will only ever see a TRUE. If it is outside, it will reset to FALSE later once the condition is no longer met.
@gsrokmix wrote:
The power off state is another thing that I'm not even quite sure I'd need. Can I just leave the button in all of the other states, and not create a seperate state for it? I'm thinking that in real life, someone buying a soda wouldn't shut the machine off.
I want the machine to go back to the take money state, after the vend & change return state. What I really want as a result is that you can't make another selection before putting more money in (which means that when switching states, the $$ entered would be reset by the state change), and also the change returned should be reset to zero at the same time.
The money should only reset to zero after a bottle is dispensed and change is returned.
You need a power off state for cleanup. For example if there is money left (e.g. if not enough money has ever been entered), that should be returned when shutting off.
@stevem181 wrote:I’m going to go against the crowd here, so feel free to ignore this post.
I don't think anyone discouraged the use of an event structure, we just did not want to overload the beginner programmer with additional concepts. 😄
