new with PLC!

[jubail]

I'm new with the PLC programming and I need help.

Implement a program to control a coin changer. A coin changer is built to return change plus dispense a $.35 candy bar. No more than three coins are to ever be used (There is no need to count the number of coins entered). Coins to be used are dimes and quarters. Write a program to accept or reject the sale based on the coins rendered. Coins rendered are checked by inputs on using push buttons or selector switches when the Request Candy Bar button is pushed.

Assume dime 2 is not allowed until dime 1 is on. Assume dime 3 is not allowed until dime 2 is on. That is, dimes enter by filling the slot for dime 1, then dime 2 and finally dime 3.



The same sequence is used for quarters.



Accept turns on with the Request Candy Bar input and enough money entered.
Change turns on with the Request Candy Bar input and an excess of money.
Reject turns on with the Request Candy Bar input when no money or not enough money is entered.

Allow the user to push all coin buttons in any sequence and then push the request button. As long as the request button is pushed, the correct lights turn on. Change the cost from $.35 to $.55 for the candy bar.

 

[surferb]

Sounds like an assignment. Ask specific questions and we'll provide specific answers.

I'm new with the PLC programming and I need help.

Implement a program to control a coin changer. A coin changer is built to return change plus dispense a $.35 candy bar. No more than three coins are to ever be used (There is no need to count the number of coins entered). Coins to be used are dimes and quarters. Write a program to accept or reject the sale based on the coins rendered. Coins rendered are checked by inputs on using push buttons or selector switches when the Request Candy Bar button is pushed.

Assume dime 2 is not allowed until dime 1 is on. Assume dime 3 is not allowed until dime 2 is on. That is, dimes enter by filling the slot for dime 1, then dime 2 and finally dime 3.



The same sequence is used for quarters.



Accept turns on with the Request Candy Bar input and enough money entered.
Change turns on with the Request Candy Bar input and an excess of money.
Reject turns on with the Request Candy Bar input when no money or not enough money is entered.

Allow the user to push all coin buttons in any sequence and then push the request button. As long as the request button is pushed, the correct lights turn on. Change the cost from $.35 to $.55 for the candy bar.

 

[Paulus]

Hello jubail,

A little OT, but, if you are in London, why are you working in 'Dimes' and 'Quarters'?
And, as surferb states, ask specific questions.
The amount of help you will get from this site is practically unlimited, but what won't happen is that we will do your assignments for you.

 

[JBJennings]

Wow, lets look at this logically...

You can't buy a $0.35 candy bar with 3 dimes. You must give change if a quarter is used in conjunction with 2 dimes. The only possible combination which generates no change and still allows a purchase is a dime and a quarter.

But... I'm not doing the assignment for you either, hopefully pointing you in the right direction. BTW, why are you using American coinage in London?

 

[geniusintraining]

Hello jubail,

A little OT, but, if you are in London, why are you working in 'Dimes' and 'Quarters'?

Very good...

I have a game that we play (our family) that reminds me of that..

Question:
There was a truck that was driving across a bridge... the weight limit was 5000lbs (or you can convert to metric )... if the truck weighed anything over 5000lbs the bridge would collapse, 1000ft in to the river....the truck weighed exactly 5000lbs

So the truck slowly started to creep across the bridged...half way a cross the bridge a large bird landed on the truck, the bird weighed 8oz (again you can convert)

The truck still continued across the bridge safely... can you tell me why they did not drop to the river below??

If anyone plays I will post the answer... this is not the best example of the game but its the only one I remember... I have not had my coffee yet

 

[surferb]

I'm game to play - but I have no idea. I'm sure you're not hitting us with a geeky statics question. And it didn't burn up fuel. I'm guessing something rediculous (subtle in the wording) - like there were supports underneath, or the bridge was 2 feet long, or no river, or something. Sorry, my best stab isn't that good. I'm off to bed. I'll see if someone solved it in the morning (afternoon for you).

Very good...

I have a game that we play (our family) that reminds me of that..

Question:
There was a truck that was driving across a bridge... the weight limit was 5000lbs (or you can convert to metric )... if the truck weighed anything over 5000lbs the bridge would collapse, 1000ft in to the river....the truck weighed exactly 5000lbs

So the truck slowly started to creep across the bridged...half way a cross the bridge a large bird landed on the truck, the bird weighed 8oz (again you can convert)

The truck still continued across the bridge safely... can you tell me why they did not drop to the river below??

If anyone plays I will post the answer... this is not the best example of the game but its the only one I remember... I have not had my coffee yet

 

[Paulus]

Hello GIT,

Is it that the truck + bird weighs 5000lb and 8oz, and not 5001lbs?

(Anything over 5000lbs - talking in lbs not oz = 5001lbs).

 

[surferb]

Humm, but the problem explicitly states, "anything over 5000lbs"...I think a bird qualifies. Heck, even the driver puts the truck over.

Is it that the truck + bird weighs 5000lb and 8oz, and not 5001lbs?

(Anything over 5000lbs - talking in lbs not oz = 5001lbs).

 

[geniusintraining]

Humm, but the problem explicitly states, "anything over 5000lbs"...I think a bird qualifies. Heck, even the driver puts the truck over.

Yes anything...

There was a scale just before the bridge... the truck with the driver weight was 5000, if it was 5000 and 1oz then the bridge would drop like a rock...

 

[surferb]

I could come up with various raunchy things the driver could do to lose the weight of bird after getting off the scale.

Yes anything...

There was a scale just before the bridge... the truck with the driver weight was 5000, if it was 5000 and 1oz then the bridge would drop like a rock...

 

[geniusintraining]

And it didn't burn up fuel. I'm guessing something rediculous (subtle in the wording) - like there were supports underneath, or the bridge was 2 feet long, or no river, or something. Sorry, my best stab isn't that good.

That was it... the key was halfway, the truck burned up 10oz of fuel.. (long bridge or bad miles per/gal) and the bird weight was 8oz... so all is good

There are other questions that are better... but they make you think

 

[surferb]

Those questions are interesting, but always frustrate me so...

That was it... the key was halfway, the truck burned up 10oz of fuel.. (long bridge or bad miles per/gal) and the bird weight was 8oz... so all is good

There are other questions that are better... but they make you think

 

[krk]

Another puzzle:

A bullet is fired from a rifle held horizontally 2m above the ground.

A second bullet is dropped from the exact same height as the rifle barrel the moment the first bullet clears the end of the barrel.

Which bullet hits the ground first?

(Ignore the curvature of the Earth and any frictional effects.)







Solution:
Obgu ohyyrgf uvg gur tebhaq ng gur fnzr gvzr.
Gur engr ng juvpu obgu ohyyrgf snyy vf qrgrezvarq ol gur sbepr bs tenivgl juvpu vf iregvpny naq vaqrcraqnag bs gur ubevmbagny irybpvgl bs gur ohyyrg sverq sebz gur evsyr.

 

[Paulus]

Here goes work for the rest of the afternoon...
Is it the bullet fired from the gun.
It's being held horizontally, but the gun is pointing down???

 

[krk]

Here goes work for the rest of the afternoon...
Is it the bullet fired from the gun.
It's being held horizontally, but the gun is pointing down???

The first bullet is fired horizontally. (no trick wording)