K
kart
Guest
hi guys i just want to know the concept of the vending machine with
threee inputs and five outputs . pls help me out inthis problem.
threee inputs and five outputs . pls help me out inthis problem.
M
Mike Treseler
Guest
kart wrote:
A prof who still uses this
problem hasn't updated his
notes it 10 years. Drop the
class, get a simulator
and learn vhdl on your own.
-- Mike Treseler
Here's a hint.
A prof who still uses this
problem hasn't updated his
notes it 10 years. Drop the
class, get a simulator
and learn vhdl on your own.
-- Mike Treseler
J
jens
Guest
input = three bills
output = five candy bars
QED!
K
kart
Guest
anyway i have to submit this in order to get thro my class
N
Nicolas Matringe
Guest
kart a écrit:
homework for you.
That's not the way you'll manage to go through your classes.
One of the rules that apply here is: Don't count on anyone to do your
homework for you.
That's not the way you'll manage to go through your classes.
A
Andy Peters
Guest
kart wrote:
OK, so you asked us for help solving a problem, but you haven't given
us any helpful supportive information. "Vending machine with threee
inputs and five outputs" is such an ambigious specification that pretty
much any bit of code will meet.
Is that the specification given to you by your professor? If so, then
he fails the class, too.
However, to answer your question, "the concept" of the vending machine
is simply that your professor is too lazy to think up a better example
of a state machine.
-a
I'll join in the game of "pile on the ignorant student."
OK, so you asked us for help solving a problem, but you haven't given
us any helpful supportive information. "Vending machine with threee
inputs and five outputs" is such an ambigious specification that pretty
much any bit of code will meet.
Is that the specification given to you by your professor? If so, then
he fails the class, too.
However, to answer your question, "the concept" of the vending machine
is simply that your professor is too lazy to think up a better example
of a state machine.
-a
Guest
The first step in solving any problem of this nature is to describe the
problem in enough detail so that you understand what is needed to
implement a solution. Diagrams are often helpful in such a
description. Engineering is problem solving. Part of the task of your
educators is to teach you how to approach problem solving. Relying on
others to do your thinking for you is not a way to learn how to solve
problems. Assuming you graduate and are hired as a design engineer,
who will solve your engineering problems for you then? Your coworkers
will not be too happy if you expect them to do your work for you. They
will have their own work to do. The members of this forum are not
willing to help someone who shows no evidence of having tried at all to
solve a problem before asking for help.
Wake up before you waste your time in college by trying to get through
without working. Think!
Charles
problem in enough detail so that you understand what is needed to
implement a solution. Diagrams are often helpful in such a
description. Engineering is problem solving. Part of the task of your
educators is to teach you how to approach problem solving. Relying on
others to do your thinking for you is not a way to learn how to solve
problems. Assuming you graduate and are hired as a design engineer,
who will solve your engineering problems for you then? Your coworkers
will not be too happy if you expect them to do your work for you. They
will have their own work to do. The members of this forum are not
willing to help someone who shows no evidence of having tried at all to
solve a problem before asking for help.
Wake up before you waste your time in college by trying to get through
without working. Think!
Charles
M
Mike Treseler
Guest
David Binnie wrote:
vhdl language for simulation and synthesis.
little overwhelming for a student
first learning about hardware and an HDL,
even if the machine is well understood.
The most important concept to understand
for the useful industrial application
of vhdl language is the synchronous process.
Useful shifters, counters and
controllers ("state machines")
are all instances of a synchronous process.
This uniformity is often lost in the fog
of logic description methods from the 1950's.
-- Mike Treseler
Yes. I am assuming it is a class on
vhdl language for simulation and synthesis.
I think such a controller is a
little overwhelming for a student
first learning about hardware and an HDL,
even if the machine is well understood.
The most important concept to understand
for the useful industrial application
of vhdl language is the synchronous process.
Useful shifters, counters and
controllers ("state machines")
are all instances of a synchronous process.
This uniformity is often lost in the fog
of logic description methods from the 1950's.
-- Mike Treseler
D
David Binnie
Guest
I understand your point but the sequential descrption of a counter is a bit
'dry' and teaching staff are all under pressure to make technology
interesting and accessible.
The one that the student's like and gain a lot from is the sequence
detector.
I agree that 'traffic lights' is overdone, all the students need to do is
Google 'VHDL traffic lights' to find a solution. Also that the conceptual
understanding is the important goal but that for many does not come until
assimilation of many examples.
I welcome any other suggestion for problems at simple sequential machine
level.
'dry' and teaching staff are all under pressure to make technology
interesting and accessible.
The one that the student's like and gain a lot from is the sequence
detector.
I agree that 'traffic lights' is overdone, all the students need to do is
Google 'VHDL traffic lights' to find a solution. Also that the conceptual
understanding is the important goal but that for many does not come until
assimilation of many examples.
I welcome any other suggestion for problems at simple sequential machine
level.
M
Mike Treseler
Guest
David Binnie wrote:
knowing what a digital controller is before I
have to design my first one.
as this is pure measurement.
However, the textbook solution
always includes a state diagram.
How about demonstrating a shift and check solution also?
That's how I do it in real hdlc controllers.
Logic synthesis has been done.
It doesn't have to be re-invented in each problem solution.
The students might say "Hey,this is easy"
complete solutions and simulation testbenches
will go a long way toward enlightenment of students.
1. Quiz show answer buttons.
2. Speed detection by echo delay
3. Speed detection by echo frequency.
-- Mike Treseler
The actual control problem is not as important as
knowing what a digital controller is before I
have to design my first one.
I like the sequence detector problem
as this is pure measurement.
However, the textbook solution
always includes a state diagram.
How about demonstrating a shift and check solution also?
That's how I do it in real hdlc controllers.
Logic synthesis has been done.
It doesn't have to be re-invented in each problem solution.
The students might say "Hey,this is easy"
Yes. A few simple examples with
complete solutions and simulation testbenches
will go a long way toward enlightenment of students.
Let's start with a few simple measurement problems.
1. Quiz show answer buttons.
2. Speed detection by echo delay
3. Speed detection by echo frequency.
-- Mike Treseler
J
John Monro
Guest
David Binnie wrote:
I have one suggestion for a simple state machine: It involves two
photo-electric sensors across the entry to a shop. The aim is to detect
and distinguish between customers entering or leaving. A bell can be
rung for customers entering or alternatively a counter can be
incremented or decremented to record the customers in the shop.
At first it seems a trivial problem, but when students consider such
possibilities customers who linger half-way into the shop but then
leave, it becomes a reasonable problem with about a dozen states.
Depending on the students it can instead be put as a problem in which
the input comes from a rotary digital tachometer that has both in-phase
and quadrature outputs. The aim then is to detect and record the nett
angular rotation, given a possible mixture of clockwise and
anti-clockwise rotations.
Regards,
John
I agree about the 'traffic lights.'
I have one suggestion for a simple state machine: It involves two
photo-electric sensors across the entry to a shop. The aim is to detect
and distinguish between customers entering or leaving. A bell can be
rung for customers entering or alternatively a counter can be
incremented or decremented to record the customers in the shop.
At first it seems a trivial problem, but when students consider such
possibilities customers who linger half-way into the shop but then
leave, it becomes a reasonable problem with about a dozen states.
Depending on the students it can instead be put as a problem in which
the input comes from a rotary digital tachometer that has both in-phase
and quadrature outputs. The aim then is to detect and record the nett
angular rotation, given a possible mixture of clockwise and
anti-clockwise rotations.
Regards,
John
N
Nicolas Matringe
Guest
Mike Treseler a écrit:
I was assigned the Vending Machine Problem (now this could make a good
new TLA ;o) in my digital electronics class. We had never heard of VHDL
at the time, we built it out of logic gates and DFFs.
Nicolas
I second to that.
I was assigned the Vending Machine Problem (now this could make a good
new TLA ;o) in my digital electronics class. We had never heard of VHDL
at the time, we built it out of logic gates and DFFs.
Nicolas
M
Mike Treseler
Guest
Nicolas Matringe wrote:
generation to generation like a flood story.
Three letters is not be enough for my acronym:
The Dreaded VMP.
-- Mike Treseler
Interesting. The problem has been passed from
generation to generation like a flood story.
Three letters is not be enough for my acronym:
The Dreaded VMP.
-- Mike Treseler
N
Nicolas Matringe
Guest
Mike Treseler a écrit:
students".
What I meant was that the problem is not tied to VHDL but has more to
do with logic design.
I am a bit conservative and stuck to the TLA form but I like your idea.
What about Infamous VMP?
)
Nicolas
It was only 10 years ago. When I say "we" I meant "me and my fellow
students".
What I meant was that the problem is not tied to VHDL but has more to
do with logic design.
I am a bit conservative and stuck to the TLA form but I like your idea.
What about Infamous VMP?
)Nicolas
P
Paul Burke
Guest
Mike Treseler wrote:
requirement using two- input logic gates".
Paul Burke
I bet some schools are still teaching "implement the following
requirement using two- input logic gates".
Paul Burke