: Homework Help with Computers/Telecomm Systems (Calling All Computer Geeks!!)



CadillacGurl
01-21-08, 03:04 PM
So Nicki went home for the weekend and forgot her textbook. I've e-mailed my professor and I'm waiting on his reply. I cannot for the life of me figure out these problems. PLEASE HELP ME!!! :crying2:

6. Using 16-bit two's complement arithmetic, show the binary value of decimal -731? Be sure to show a 16-bit answer.

7. A computer with a 32-bit address has how many storage locations? Show the answer in the form 2x.

8. A computer has 64-bit integer values. What is the largest positive (signed) value on this computer? What is the largest unsigned value? Show all answers in the form 2x.

9. How many bits are necessary to support 128 combinations? 1024? 2 million?

CadillacSTS42005
01-21-08, 03:54 PM
ahahahahaa
yea
no way in figgen hell i could help you
i have C++ for dummys in my room but thats binary code completely different than the IF THEN statements in C++
goodluck Nik love ya

common guys help her out

BigJon
01-21-08, 04:17 PM
i e-mailed my buddy that went to school for that stuff hope he e-mails me back in time.... and remembers... any of it

CadillacGurl
01-21-08, 04:29 PM
i e-mailed my buddy that went to school for that stuff hope he e-mails me back in time.... and remembers... any of it

Thanks I appreciate any help.

CadillacGurl
01-21-08, 04:32 PM
ahahahahaa
yea
no way in figgen hell i could help you
i have C++ for dummys in my room but thats binary code completely different than the IF THEN statements in C++
goodluck Nik love ya

common guys help her out

haha ok I still love you 2 :bouncy:

ejguillot
01-21-08, 04:44 PM
So Nicki went home for the weekend and forgot her textbook. I've e-mailed my professor and I'm waiting on his reply. I cannot for the life of me figure out these problems. PLEASE HELP ME!!! :crying2:

6. Using 16-bit two's complement arithmetic, show the binary value of decimal -731? Be sure to show a 16-bit answer.

7. A computer with a 32-bit address has how many storage locations? Show the answer in the form 2x.

8. A computer has 64-bit integer values. What is the largest positive (signed) value on this computer? What is the largest unsigned value? Show all answers in the form 2x.

9. How many bits are necessary to support 128 combinations? 1024? 2 million?

Try doing a google search on binary arithmetic... the answers are out there. That said, here are some hints (I'm not just going to give you the answers, if I do that won't help you for the next set of problems).

For 6, you have 1 bit for the +/-, and 15 for the number (I believe the +/- bit is on the left). Your answer will be a 16 digit string of 1's and 0's.

For questions 7, 8, and 9, remember that the answers are 2^xx (xx being the number of bits. So for 7, how many address bits are there? For 8, remember that you lose a bit for the +/- signing. And for 9, those are all 2^xx answers, so for example 128 is 2^7, or 7 bits.

I'm sure that you can take it from here, good luck!

CadillacSTS42005
01-21-08, 05:00 PM
i read that
and i still have no clue how to help her hahaha

CadillacGurl
01-21-08, 05:10 PM
Try doing a google search on binary arithmetic... the answers are out there. That said, here are some hints (I'm not just going to give you the answers, if I do that won't help you for the next set of problems).

For 6, you have 1 bit for the +/-, and 15 for the number (I believe the +/- bit is on the left). Your answer will be a 16 digit string of 1's and 0's.

For questions 7, 8, and 9, remember that the answers are 2^xx (xx being the number of bits. So for 7, how many address bits are there? For 8, remember that you lose a bit for the +/- signing. And for 9, those are all 2^xx answers, so for example 128 is 2^7, or 7 bits.

I'm sure that you can take it from here, good luck!

It's honestly all latin to me... I've been looking and nothing makes sense...

CadillacGurl
01-21-08, 05:17 PM
I did a good search its just I don't understand what number is +/- and which is = 1 or 0...

CadillacGurl
01-21-08, 05:18 PM
What's sad is this is our first hw assignment in the class....

CadillacGurl
01-21-08, 05:23 PM
I actually found an article on wiki which is kind of helping... http://en.wikipedia.org/wiki/Binary_numeral_system

CadillacGurl
01-21-08, 05:51 PM
Ok I'm stuck on questions 6 & 8 HELP!!

gary88
01-21-08, 06:14 PM
Whatever class that is, remind me to never take it.

CadillacSTS42005
01-21-08, 07:13 PM
ya really
i failed computer basic in HS
java and C++ what a bia

HITMONEY
01-21-08, 08:52 PM
What is this, a pre-requsit to become a damn Astronaut or what.

Jeesh.

Rolex
01-21-08, 10:03 PM
http://img.photobucket.com/albums/v305/rolex/nerds.jpg
nnnnnNNNNEEEEEERRRDDDDDSSS!!!!!!



I have nothing to contribute here. :hide:

JTraik
01-21-08, 10:20 PM
Your lucky, theres a MicroElectronics student on board! :highfive:

Is this a Digital Systems class? I took one of these a few years ago, pay attention because this is really cool and powerful stuff! Wait til you get in the lab, its a blast.



6. Using 16-bit two's complement arithmetic, show the binary value of decimal -731? Be sure to show a 16-bit answer.

You should have learned how to add binary in class. When converting base 10 to base 2... for example take a binary number such as 010011. You start from the far right least significant bit (LSB) to the far left most significant bit (MSB). To go from base 2 to 10 start on the right side of the binary value and multiply the 1 or 0 by a consecutive 2^n ....

The leftmost digit is your sign indicator, 0 for positive, 1 for negative

Right to left.... [1*(2^4)] + [0*(2^3)] + [0*(2^2)] + [1*(2^1)] + [1*(2^0)] = 19 on a base 10.

You have 731 base 10 and need to go base 2/binary. Even easier... you consecutively divide the number by 2 (for base 2) and the remainder is your binary value... however the order of your binary digits is LSB to MSB. So...

731/2 = 365 R 1, 365/2 = 182 R 1, 182/2 = 91 R 0, 91/2 = 45 R 1, 45/2 = 22 R 1, 22/2 = 11 R 0, 11/2 = 5 R 1, 5/2 = 2 R 1, 2/2 = 1 R 0, 1/2 = 0 R 1.

So that gives us 01011011011, if you work that out the same way as above you get +731. Now to give that a negative value you invert your binary number and then add a 1 to it. So... our new number is 0100100100 + 1 = 1100100101 see the left digit go to 1! Thats only 10 digits, for 16 digits just put 0's on the left before you convert. 0000000100100100 + 1 = 1111111011011011 = -731. To prove this you subtract your MSB all the way to the LSB and voila!

1111111011011011 = -731



8. A computer has 64-bit integer values. What is the largest positive (signed) value on this computer? What is the largest unsigned value? Show all answers in the form 2x.


Now that you know how they add... haha have fun! 01111111111111111111111111111111111111111111111111 111111111111111

CadillacGurl
01-21-08, 11:26 PM
Whatever class that is, remind me to never take it.

Introduction to Computers and Telecommunications

JimHare
01-22-08, 12:13 AM
{Rant on}
I've been in the computer industry since 1979. I'm hardly an expert, but I've made my living at it for dam' near 30 years. And those have got to be some of the most ridiculous questions I've ever seen asked of a student in the 21st Century, especially in an INTRO class. No wonder most software is crap. Kids spend too much time learning this nonsense, and not enough about what makes Good Software. It may have been important to know 30 years ago (hint hint) but unless you plan on building your own microprocessors or writing your own compiler it's going to be completely useless to you once you graduate. You should be studying the kinds of things that will be important in 10 years - nanotechnology, neural networks, molecular computing, database theory, and so on. Good software is far harder to produce than good hardware.

Don't mean to offend anyone who gets a boner doing this stuff but c'mon.. :) Two's Complement? Give me a break..Just out of curiousity, gurl, what is the copywrite date of that textbook?
{Rant off}

eldorado99
01-22-08, 12:36 AM
{Rant on}
I've been in the computer industry since 1979. I'm hardly an expert, but I've made my living at it for dam' near 30 years. And those have got to be some of the most ridiculous questions I've ever seen asked of a student in the 21st Century, especially in an INTRO class. No wonder most software is crap. Kids spend too much time learning this nonsense, and not enough about what makes Good Software. It may have been important to know 30 years ago (hint hint) but unless you plan on building your own microprocessors or writing your own compiler it's going to be completely useless to you once you graduate. You should be studying the kinds of things that will be important in 10 years - nanotechnology, neural networks, molecular computing, database theory, and so on. Good software is far harder to produce than good hardware.

Don't mean to offend anyone who gets a boner doing this stuff but c'mon.. :) Two's Complement? Give me a break..Just out of curiousity, gurl, what is the copywrite date of that textbook?
{Rant off}

Very good point Jim, however I feel that spending just a little time on this in an intro class is a good thing because it gives you perspective and some basic idea of how a computer thinks. People who don't know a thing about computers don't usually have any idea how a letter appears on their screen for example. That said, I agree with you that it should not be a major focus.

ewill3rd
01-22-08, 06:53 AM
My first instinct was to translate that number into Hexadecimal and then make a binary for each hex digit.
I think JT may be closer to correct.
If you had hit me with those questions about 5 years ago I could have helped you.
As stated by a computer guy.... there isn't much need for that kind of information once you get out of school.
It is good to understand how it works.... but....

Any questions on there about fuel injection?
:D

CadillacGurl
01-22-08, 08:03 AM
{Rant on}
I've been in the computer industry since 1979. I'm hardly an expert, but I've made my living at it for dam' near 30 years. And those have got to be some of the most ridiculous questions I've ever seen asked of a student in the 21st Century, especially in an INTRO class. No wonder most software is crap. Kids spend too much time learning this nonsense, and not enough about what makes Good Software. It may have been important to know 30 years ago (hint hint) but unless you plan on building your own microprocessors or writing your own compiler it's going to be completely useless to you once you graduate. You should be studying the kinds of things that will be important in 10 years - nanotechnology, neural networks, molecular computing, database theory, and so on. Good software is far harder to produce than good hardware.

Don't mean to offend anyone who gets a boner doing this stuff but c'mon.. :) Two's Complement? Give me a break..Just out of curiousity, gurl, what is the copywrite date of that textbook?
{Rant off}

The big thing to talk about in that class is "When did you build your first computer?" Ha.... I got shunned after that...

The textbook is Systems Architecture 5th Edition by Stephen Burd and its copyright is 2005.

CadillacGurl
01-22-08, 08:04 AM
Any questions on there about fuel injection?
:D

Haha I WISH!!! I'd pass with flying colors!

ewill3rd
01-22-08, 08:30 AM
I actually earned a diploma from the Cleveland Institute of Electronics in Automotive Electronics.
I had to do tons of electronic study including Boolean Algebra, binary addition and subtraction, number conversions.... tons and tons of stuff.
I even had to write programs in hex for an old Motorla processor to display some stuff on a breadboard lab station. Pain in the butt.
Strangely I learned more about that stuff doing an automotive course than I did when I was a computer programmer. ?

When did I build my first computer? Wow, that was a long time ago. Probably around '98 somewhere.
My first one I bought retail, the second I bought built at one of those custom shops, one in St. Louis. All the other ones since then I built except one time right when I moved here, I needed one bad and didn't know where to go locally to find parts so I bought this HP I use at work, and one I bought for my son because it was cheaper than building one... which in retrospect... I wish I had built one instead rather than the POS Dell I bought.

How are you coming on your homework?

CadillacGurl
01-22-08, 08:40 AM
I already turned my hw in last night. It had to be in by 6PM Central Time.

JimHare
01-22-08, 09:42 AM
Very good point Jim, however I feel that spending just a little time on this in an intro class is a good thing because it gives you perspective and some basic idea of how a computer thinks. People who don't know a thing about computers don't usually have any idea how a letter appears on their screen for example. That said, I agree with you that it should not be a major focus.

I taught night school comp sci at a community college for 17 years. When I started, Windows was still an unknown quantity, and everything came from the C:\> prompt. Back then, it helped a LITTLE bit for people to know what went on, but as time passed that knowledge became less and less useful. It's more important for a 'regular' computer user to understand how her programs interact, why things go wrong sometimes, and to feel, above all, then when the computer blows up, it's NOT HER FAULT. I had dozens and dozens of students who felt that it was their fault, somehow, when things broke on the computer. I spent hours explaining that they weren't dumb, the computer was. Bug-ridden software, confusing user interfaces, useless features, erratic behavior, all these things contributed to making the average Jane or Joe think that it was their fault the damn thing didn't work right.

For a vast majority of all computer users in this day and age, knowing how a letter appears on the screen is meaningless. What 99% of all users want to know is, "How do I make this sentence bold?" or "How do I put this spreadsheet in my email?"

I usually spent about half an hour explaining how a keypress turned in to a bunch of zeros and ones, then in to a bunch of electrical signals that somehow the computer managed to keep track of (usually..) but after that, it really didn't matter. They wanted to get their work done, not have to worry about translating base 10 into two's complement....

I don't mean to get all curmudgeonly on everyone, but I've spent a long time helping people with computers and I get razzed a the "high priests" who try so hard to keep the secrets of the magic from the unwashed masses, if you get my drift. Gurl, good luck with the class, but don't obsess over it.

codewize
01-22-08, 09:53 AM
I'm a network engineer. I do binary math every day. My wife and I discuss binary over dinner and I don't understand those questions.

What the heck is the 2x thing all about.

CadillacGurl
01-22-08, 09:59 AM
I taught night school comp sci at a community college for 17 years. When I started, Windows was still an unknown quantity, and everything came from the C:\> prompt. Back then, it helped a LITTLE bit for people to know what went on, but as time passed that knowledge became less and less useful. It's more important for a 'regular' computer user to understand how her programs interact, why things go wrong sometimes, and to feel, above all, then when the computer blows up, it's NOT HER FAULT. I had dozens and dozens of students who felt that it was their fault, somehow, when things broke on the computer. I spent hours explaining that they weren't dumb, the computer was. Bug-ridden software, confusing user interfaces, useless features, erratic behavior, all these things contributed to making the average Jane or Joe think that it was their fault the damn thing didn't work right.

For a vast majority of all computer users in this day and age, knowing how a letter appears on the screen is meaningless. What 99% of all users want to know is, "How do I make this sentence bold?" or "How do I put this spreadsheet in my email?"

I usually spent about half an hour explaining how a keypress turned in to a bunch of zeros and ones, then in to a bunch of electrical signals that somehow the computer managed to keep track of (usually..) but after that, it really didn't matter. They wanted to get their work done, not have to worry about translating base 10 into two's complement....

I don't mean to get all curmudgeonly on everyone, but I've spent a long time helping people with computers and I get razzed a the "high priests" who try so hard to keep the secrets of the magic from the unwashed masses, if you get my drift. Gurl, good luck with the class, but don't obsess over it.

Fun.... I know a decent bit of knowledge to get me passed this course just some of the questions he asks come out of now where and he doesn't explain them. He just gives us paper that "supposedly" explains them. Its frustrating at times but you just gotta go with the flow.

Is it a mandatory thing to know how to build your own computer? My teacher was disappointed when I told him I never did (let alone I'm the only girl in the class). I mean heck I've installed an old school packerd (sp?) bell in our new house for when my little cousin comes over. I know how to hack into people's wireless routers haha but sadly that doesn't count toward our grades :dammit:

I'm the annoying student who asks a lot of questions, I get the "shut up now" look from guys along with that proff sometimes. I know I'll be back here posting next week for my homework lol.

JTraik
01-22-08, 10:37 AM
{Rant on}
It may have been important to know 30 years ago (hint hint) but unless you plan on building your own microprocessors or writing your own compiler it's going to be completely useless to you once you graduate. You should be studying the kinds of things that will be important in 10 years - nanotechnology, neural networks, molecular computing, database theory, and so on. Good software is far harder to produce than good hardware.


I'm very surprised that someone in your field would say that. When you graduate you should have a full understanding of what is going on... cursory knowledge is great if your doing assembly... but the real money goes to engineers and problem solvers.

I am a nanotech/microE student and I find this knowledge very useful and supplemental to my understanding of the field.

"Good software harder to produce that good software"... Are you referring to engineering, manufacturing, design... what?

JTraik
01-22-08, 10:38 AM
What the heck is the 2x thing all about.

Instead of solving for 64 bit she can do it in 32 bit... still is misleading.

ewill3rd
01-22-08, 11:59 AM
One of my wife's coworkers is a math genious, and I do mean that in the most literal sense.
He suffers from a bad case of Parkinson's. He comes up with the coolest stuff.

He has one of my favorite T shirts of all time, it says:

"When it comes to understanding binary, there are 10 kinds of people"
:histeric:

CadillacGurl
01-22-08, 12:02 PM
:lol:

codewize
01-22-08, 09:30 PM
Ahh OK makes more sense now. Never really worked with 64 bit binary as most of my binary is used for networking and not process calculations.

IP is 32 bit well IPv4 is 32 bit so that's my fluency level I guess. That I understand forward and backward and if you've ever taken a Cisco exam you'll soon realize that's a necessary skill.



Instead of solving for 64 bit she can do it in 32 bit... still is misleading.

CadillacGurl
01-27-08, 11:35 AM
Homework time again. Just need help on two questions :)

3. Using transistors, draw a circuit that implements a NOT function.


4. Given a coil that has 12 turns, an area of 5 cm, a length of 4 cm, and a core of steel, how many henrys does the coil produce?

CadillacGurl
01-28-08, 12:08 AM
anybody? :(

ewill3rd
01-28-08, 07:23 AM
I saw your ? yesterday. I'd have to dig out my electronics books to help you, and I am not even sure where they are.

Is there any frame of reference for the NOT gate?

I guess you already googled for a formula for henries?

JimHare
01-28-08, 08:58 AM
I'm very surprised that someone in your field would say that. When you graduate you should have a full understanding of what is going on... cursory knowledge is great if your doing assembly... but the real money goes to engineers and problem solvers.

I am a nanotech/microE student and I find this knowledge very useful and supplemental to my understanding of the field.

"Good software harder to produce that good software"... Are you referring to engineering, manufacturing, design... what?

I'm referring to the well-established concept that hardware is, more or less, subject to well-defined mechanical/engineering/electronic rules and formulas. Notwithstanding the incremental improvements in such things as disk storage, microprocessor speed and function and so on, hardware design is fairly straightforward. However, designing and building software is much more of an ART than a SCIENCE, at least in terms of understanding and implementing a machine-human interface. It's software that differentiates a computer from a toaster. Without good software that is usable, understandable, predictable and overall, HELPS a person do a job, the hardware is useless, no matter how slick.

My comments were not directed at the admittedly talented, and necessary, people like network engineers and hardware designers who build these things that we use. They were directed at the 99.99% of OTHER computer users who just want to get their job done.

I'm sorry if I was misunderstood - that was not my intent.

ewill3rd
01-28-08, 09:05 AM
I guess here is some good info. http://en.wikipedia.org/wiki/Inductance
Your text book probably has more in it than I can find on the web though.
Wish I could help more.
:(

CadillacGurl
01-28-08, 10:04 AM
It's alright I appreciate it. I'm looking through the handouts and whatnot to see if there's anything. Thanks Ewill.

CadillacGurl
02-02-08, 09:32 PM
New hw! I got most of them done I would just let to check.

1. Given the following truth table:

A B C F
0 0 0 1
0 0 1 1
0 1 0 0
0 1 1 0
1 0 0 0
1 0 1 0
1 1 0 1
1 1 1 0

Draw the equivalent circuit using AND and OR gates (please do not reduce it).



2. Given the following circuit, create the equivalent truth table.

http://img.photobucket.com/albums/v437/surovy2543/pictureequation.jpg

3. What is the quiescent state (the state in which no changes happen) to an SR latch built of two NOR gates? (Construct the truth table.)

4. Write the microinstruction(s) in binary using the layout from slide number 4, and similar to the examples we performed in class, for each of the following machine instructions:

a. Multiply xvalue,yvalue

b. Decrement counter

The variables counter, xvalue, and yvalue are all stored in RAM. Assume read and write operations take 2 microinstructions. Further assume that:
• the memory address of the variable xvalue is stored in REG A,
• the memory address of variable yvalue is stored in REG B and
• the memory address of counter is stored in REG C.

lawfive
02-03-08, 08:54 AM
Do you ever actually go to class, Nik? If so, what do you do while you're in there?

ewill3rd
02-03-08, 09:19 AM
I wish you had gotten me 5 years ago, I probably could have answered that stuff.
I'd have to hit the books to answer those.

CadillacGurl
02-03-08, 09:50 AM
Do you ever actually go to class, Nik? If so, what do you do while you're in there?

It's an online course...

JTraik
02-03-08, 05:53 PM
These are very fundamental questions. Your notes/handouts should contain everything you need.