Digital Circuit Problem Need Help!

[sas4579]

A digital circuit to detect low tire pressure on a motorcycle.

The circuitry receives two 6-bit binary data from the tire pressure sensors. One for the front tire, the other for the rear. For example, at 3 psi the sensor outputs b'000011.

The maximum tire pressure specified for each motorcycle tire is 50 psi.

Design the circut so that when the pressure of one tire is at least 4 psi lower than the other, it activates one of the two warning signals WF AND WR. If the front tire pressure is lower then WF=1 OR if the rear tire pressure is lower than WR=1 then all conditions are WF=WR=0.

Design circuit using full adders and any other types of gates, capture the design using circuit diagram in conjuction with Boolean equations.

Plug in pre selected numbers to verify if your design works. Front tire at 48 psi and reare at 8 psi.

Really confused please help!!!!

Thanks

 

[Markbnj]

I know, it is confusing. Let me help: this is homework. If you want help with homework you should at least _try_ to do a little bit of it yourself first. Maybe post some of your thinking so far, as opposed to just ctrl-c/ctrl-v the text from the assignment.

 

[PottedMeat]

A digital circuit to detect low tire pressure on a motorcycle.

The circuitry receives two 6-bit binary data from the tire pressure sensors. One for the front tire, the other for the rear. For example, at 3 psi the sensor outputs b'000011.

The maximum tire pressure specified for each motorcycle tire is 50 psi.

Design the circut so that when the pressure of one tire is at least 4 psi lower than the other, it activates one of the two warning signals WF AND WR. If the front tire pressure is lower then WF=1 OR if the rear tire pressure is lower than WR=1 then all conditions are WF=WR=0.

Design circuit using full adders and any other types of gates, capture the design using circuit diagram in conjuction with Boolean equations.

Plug in pre selected numbers to verify if your design works. Front tire at 48 psi and reare at 8 psi.

Really confused please help!!!!

Thanks

/diy on 4chan would be happy to do your homework for free

 

[MrDudeMan]

I'd be happy to help explain this, but you need to give honest effort first. The whole point of homework is to learn and you won't be learning if someone else solves the problem.

 

[sas4579]

Well my theory is that you have two inputs with two outputs. Either the warning light is on or not are the outputs and the two tires are the inputs. I am not sure if I need to use a half adder or a full adder in this case. Also do i need to use 2's complement to find the difference between the two pressures to activate the warning light if are more than 4 psi apart?

 

[sas4579]

Do I need to set up a truth table to show from 0 to 50 psi

 

[skimple]

Do you need to set up a truth table? No. Its not a requirement unless your homework says so.

Would setting up a truth table help you understand the relationship between the inputs and outputs? I'm thinking - yes.

Pretty easy in Excel to build a 12 bit truth table.

 

[festa_freak]

You are asking questions that only your instructor can answer. You need a clear cut goal and process for this assignment.

 

[sdifox]

but psi reading is analogue...

 

[PottedMeat]

needs at least? (damn it's been a long time)

1. difference
2. sign (which wheel)
3. combi logic for >4
4. combi logic for which/both warnings?


...could probably figure it out with a 6 x 6 -> 2 output table

 

[skimple]

Start with:

r5 r4 r3 r2 r1 r0 f5 f4 f3 f2 f1 f0 | wf wr
0 0 0 0 0 0 0 0 0 0 0 0 | 0 0
.
.
.
.

Of course wf = wr = 0 in the first line assumes that you are only interested in the delta between f and r and don't have a threshold pressure.

Once you fill out your truth table, write the formulas for the conditions when wf and wr are true. Simplify down to the fewest inputs and select your gates.

 

[sas4579]

Skimple i am not understanding you and we are to come up with the logic design for the warning light to come on with the specifications noted so thats why i am a bit confused.

 

[sdifox]

Skimple i am not understanding you and we are to come up with the logic design for the warning light to come on with the specifications noted so thats why i am a bit confused.

No home work help here....

 

[Rubycon]

Hmmm, I dunno aren't you concerned with the RFI effects of the typical rice rocket high energy ignition system? Will cross interleaved Reed-Solomon code suffice?

A piezo-resistive bridge silicon transducer coupled to a simple comparator is all you really need to switch a transistor to high to make the fleabag idiot light glow on the scooter's speedo!

But if you want a digital readout in kPa. Oh that works too. Don't forget these sensors are very sensitive to ambient temperature as well (reference instrumentation keeps them in controlled ovens). So you must also have a temperature sensor to offset this.

Oh and aren't the tires tube? Tube tires can develop static from deflection when rolling. That's another source of EMI that must be dealt with.

 

[Possessed Freak]

Recommend skipping a few steps, placing all the problematic pieces into a "black box" to return the desired effect (I *really* hated it when the professor used to include black boxes generating output without knowing what it was doing).

 

[videogames101]

This is like 3 lines in any HDL.

If you're supposed to do this "by hand" I recommend http://en.wikipedia.org/wiki/Digital_comparator which provides a logical equation for the conditions you're looking for, and should be easy to convert to a digital circuit.

 

[NutBucket]

I "cheated" in my digital circuits class by doing some of the assignments with Altera instead of discrete gates like the rest of the class. Prof didn't mind. This was 2002-ish.

 

[Jaepheth]

Hmmm, I dunno aren't you concerned with the RFI effects of the typical rice rocket high energy ignition system? Will cross interleaved Reed-Solomon code suffice?

A piezo-resistive bridge silicon transducer coupled to a simple comparator is all you really need to switch a transistor to high to make the fleabag idiot light glow on the scooter's speedo!

But if you want a digital readout in kPa. Oh that works too. Don't forget these sensors are very sensitive to ambient temperature as well (reference instrumentation keeps them in controlled ovens). So you must also have a temperature sensor to offset this.

Oh and aren't the tires tube? Tube tires can develop static from deflection when rolling. That's another source of EMI that must be dealt with.

Show off


...

Good show.

 

[ussfletcher]

Skimple i am not understanding you and we are to come up with the logic design for the warning light to come on with the specifications noted so thats why i am a bit confused.

Not to be too discouraging, but if you don't understand what he was attempting to tell you in the context of your question, then you need to spend some time with your teacher/professor going over the basics.

 

[skimple]

I "cheated" in my digital circuits class by doing some of the assignments with Altera instead of discrete gates like the rest of the class. Prof didn't mind. This was 2002-ish.

Using a $200 FPGA to perform 50 cents worth of logic?

Are you German?

 

[PottedMeat]

Using a $200 FPGA to perform 50 cents worth of logic?

Are you German?

altera's free software -> probably does the reduction for you

 

[NutBucket]

I had it available at work. Cost = $0. Thanks taxpayers

And these were antiquated parts even in 2002. Single 5V supply, 24 pin DIPs. PLDs, not FPGAs.

EDIT: My dad is Swiss...so close enough!

 

[twinrider1]

 

[Ken g6]

Also do i need to use 2's complement to find the difference

Do you? If you use 2's complement, how many different kinds of outputs (that should light a warning light) could you have? Remember, you only need to find outputs where the absolute difference is > 3, a.k.a. >=4.

Now, I suggest you look at 1's complement. How many different kinds of outputs (that should light a warning light) could you have now? :sneaky:

 

[skimple]

Does it have HDMI?