General "rules"

0. This is a fun trivia game....

1. Cumulative Trivia is different from Cumulative Quizzes. The main areas of difference are set off in a quote block for clarity:

(1). The objective: Trivia, info, and tidbits related to the world of computers.

(2). This is a fast-moving thread: 48 hours (max) from question post to the next question is the limit.

(3). Research IS allowed... online, books, friends, etc. The one caveat is if you don't know the info from your own knowledge, simply state the specific reference (& hyperlink, if internet-based). This is not a battle of individual "smarts" or memory retention, but an exchange of info and trivia.

(4). Current questioner: visit at least daily (preferably a few times a day while your question is active) to check replies; you can give hints if you like. If the question is not aswered to your satisfaction within 48 hours (maximum) of your first post of your question, then state the answer (and reference, if you used one) and either ask a new question or pass the question to another participant.

(5). Respondants: Check back by that 48 hours after you post your reply, because the original author will have confirmed or rejected your reply by then. You are expected to post your new question by the end of the 48 hour limit from the previous question...

(6). The basic idea is that anyone, even computer neophytes and non-native English speakers, can effectively participate :) You need only be able to locate or research info... databases and reference books are cool :cool: .


2. All questions need to be related to computers, software, computer history, historical people in computing, etc.

3. If the question ages 48 hours form the original post time/date with no correct reply (as acknowledged by the author), then the 1st one who posted the "right" answer gets the next question; if that is ambigious, then the person who replied immediately after the author's original question can go next & keep the quiz back on track. :)

4. Naturally, question makers should know the exact answer to their question before posting, LOL....

5. Again, research is OK, both for questions and for answers. But try and choose questions that are of at least marginal interest to "average" people.... the kind of general trivia that CFC people might enjoy discussing in real life.

6. Note: researching questions, esp. with internet search engines and reference books will likely add to (or refreshen) your general knowledge for the Cumulative Computer Quiz thread.


rev 1.00, 09Jul02... .

Question 1:

Easy....

What was the name of the first PC hard drive defragmentation program, and what was the name of the program's author?

Hint#1: Try looking for terms such as "defrag" and "fragmentation" and "198" (the program came out in the 1980's).

Another hint will follow in a few hours if no answer.

This is not the answer, but I thought this metaphor was weird enough to quote:

"DEFRAG reorganises the hard drive of the industry by taking the lost files of silliness and displaying them on the screen saver of ridicule, while working in gratuitous references to professional wrestling wherever possible. Defrag has never won a Walkley, but Linus Torvalds suggested Kerrie Murphy was on drugs after she theorised the Linux penguin would lose a deathmatch against the BSD Deamon."

http://australianit.news.com.au/topics/0,7202,columns_defrag,00.html

I'm going to try this without researching. I believe it was the Norton Disk Doctor.

Well, the search engine did not seem to help out too much (too hard to extract the exact info) when I tried to use it to see what ya'll might locate.

So I'll state the references and answer, and choose to pass the question to the closest answer.

References:
- My original box & manuals of Norton Utilities 4.5 (1988).
- Using the original program Spinrite in 1988-89.
- 1991 Microsoft DOS 5.0, manual page 207-08.
- http://grc.com/

Answer:

Steve Gibson wrote a program calle "Spinrite" in 1988 that could do a lot of things, including the now-commmon defrag. Others followed shortly. My Norton Utilities 4.5 from 1988 does not have Speedisk (Peter Norton's defrag program).... but NU jumped right on it, and even MS eventually followed suite. Originally, defragging was even touted (mainly by Gibson) to extend the life of a dard drive because the heads and servos did not have to move around as much (HD crashes were more common back in 1988).

"Spinrite" (much changed!) is still in existance today, and currently in version 5. It no longer defrags, changes sector interleaves, or supports MFM and RLL drives... but it does do an excellent job of predicting, detecting, and fixing hard drive errors and recovering from certain kinds of data loss. The program is $89, however, and is not really the best value for home users with modern (reliable) hard drives.


As a historical note, here is Microsoft's original method, on page 207-08 of their MS DOS 5.0 manual (I still have mine) to compete with Gibson's Spinrite. I sh!t you not:

"If your system is reading and writing information more slowly than usual, the files on your disk might be fragmented. If you don't have a disk-compaction program ... you might want to compact your disk by reformatting"

:lol:

The "Microsoft Solution!!" Reformat your drive! Why not take out a hammer and bash your machine to bits? No more "disk compaction" worries, right?!

But Microsoft, ever the master of the obvious, went on to thoughfully warn: "... the FORMAT command deletes all files on your hard disk." Hmmm... yup, with no files, fragmentation should not be an issue for the average user ;).

Micro$oft actually listed this as the third of the 3 "advantages" (as MS saw it) of wiping out your hard drive:

"- Doesn't require you to purchase additional software."

Gee M$, how thoughtful!!!!

No need for us to support innovative software authors and companies like Gibson and Norton!! But a year or so later, MS put the true innovators out of business with the release of MS DOS 6.xx.

M$ stole the utility and included the DOS command, "DEFRAG", as a command prompt defragger for the first time. This effectively ended profitable independent innovation in this area.



Ainwood's reply of "Norton Disk Doctor" (aka NDD) is actually not a defragmenter.... NU's Speedisk is the defragmenter.

But.... since ainwood was the closest, I'll pass the next question to Ainwood....

So it's your question, Ainwood!


EDIT: Add more info.

Well, I guess you could always have backed-up to another hard-disk (or even a whole bunch of 5 1/4" floppies :eek: ) before the reformatting!

My question: When was the first spreadsheeting program developed, what company developed it, and what was it called?

"If your system is reading and writing information more slowly than usual, the files on your disk might be fragmented. If you don't have a disk-compaction program ... you might want to compact your disk by reformatting"



The "Microsoft Solution!!" Reformat your drive! Why not take out a hammer and bash your machine to bits? No more "disk compaction" worries, right?!

But Microsoft, ever the master of the obvious, went on to thoughfully warn: "... the FORMAT command deletes all files on your hard disk." Hmmm... yup, with no files, fragmentation should not be an issue for the average user .

Micro$oft actually listed this as the third of the 3 "advantages" (as MS saw it) of wiping out your hard drive:

"- Doesn't require you to purchase additional software."

L OOOO L
L O O L
L O O L
LLLL OOOO LLLL

Originally posted by ainwood
Well, I guess you could always have backed-up to another hard-disk (or even a whole bunch of 5 1/4" floppies :eek: ) before the reformatting!

My question: When was the first spreadsheeting program developed, what company developed it, and what was it called?

The earliest one I can think of is EZ something. Then they got a bunch of money and became EZCORP but I think they didn't do well after they got bigger.

Not the one I was after. :)

Now I'm starting to remember more. EZ-Calc was a clone of VisiCalc. Is that the one?

This is also the "killer app" that was responsible for really fueling the massive growth of the PC!!! And I remember it well, drooling over it, but unable to afford either it or a PC as a college student :( .

The spreadsheet was VisiCalc, and I know for a fact it ran on the TRS-80, The Apple II, and the IBM PC, and maybe even more PCs of the era. I know 1983, and I think also 1982, were years of the Spreadsheet. So I'll say it came out in 1982. I believe the company name was VisiCalc, as well as their flagship product.

OK, I think VisiCalc changed its name to VisiCorp when it got bigger.

(Not intended as an answer: There was a later company that tried to compete with VisiCalc. That company's name was Visi-On. Don't you love these cute 1980s company names?)

It was visicalc. It came out in 1979.:goodjob:

I'll pass it to sumthinelse.

Wow! 1979! They really had the world by the horns, but fumbled the football....

Hey sumthinelse, it's your question :)

Sorry about that. I was out in the monsoons, literally.

For Intel processors 8086, 286, 386, 486, Pentium you can buy an "ICE" machine from Intel. What does "ICE" stand for and what does it do?

Yes, I know the answer is easy to find but it's educational....

Well, seeing as research is allowed, I had a look. I presume you weren't after "Indiana Computing Educators".

Rather than put the answer I found, could you expand the question to also include an explanation of the term?

No need to research that one. :p

ICE stands for "in-circuit emulation".
An ICE device acts as a "normal" CPU but is controlled by the actual CPU. It monitors the bus for certain events to set a breakpoint for the CPU. Once this happens, the CPU gets into ICE mode and can perform certain functions specified in the instruction set.

In-circuit emulation is a hardware emulation method not only used by Intel, but for Intel processors it fulfills certain task like breakpoint handling. It considerable speeds up the CPU.
:D

Explain the term? Er, that's what you are supposed to do -- tell me what an intel "ICE" machine is.

The three letters are the starting letters of an intel product.

I would search for "486 ice" "pentium ice" etc.

Originally posted by Lucky
No need to research that one. :p

ICE stands for "in-circuit emulation".
An ICE device acts as a "normal" CPU but is controlled by the actual CPU. It monitors the bus for certain events to set a breakpoint for the CPU. Once this happens, the CPU gets into ICE mode and can perform certain functions specified in the instruction set.



Correct. We called it "In Circuit Emulator." really the same thing.

When your machine has a hard-to debug bug (how the **** did it do that???), for example, you can get a trace of the instructions and other cycles that led up to the error. Expensive but useful. You have to take out the pentium (or 486 or whatever) chip and replace it with the ICE probe. Be careful not to bend those pins!

Lucky, you are up!

Hmm, what could be informative?! :lol:

Which law describes the constant further development in the semiconductor industry (computer chip industry)? Name it and describe it!

Yes, that is good.
:D

Moore's Law. It states that the speed of microprocessors
will double every 2 (?) years.

Moore's Law. It states that the speed of microprocessors
will double every 2 (?) years.
Make that 18 months ;).... For awhile, some pundits have been predicting the demise of it, but so far, it's held up for over 20 years.....

Yes and no, CPU speed doubling every 18 months is the common interpretation of it! :yeah:

But WHAT does it exactly say (HINT: what does a CPU consist of?)?
:D

That the number of transistors on a CPU will double every 18 months. :)

Yep!
The law was actually inspired by the linear development in semiconductor technology, the linear decrease in structure width. Moore deducted from that, that the number of transistors on an integrated circuit would also grow in a linear way. :yeah:

Either of you, Serutan or ainwood, go on.
:D

Don't think its really fair that I go! I only answered the last little bit!

And serutan only answered the first bit! Starlifter corrected the middle bit and you appended the last bit! :rolleyes:

Anyone of you, just ask a question!!!
:D

Originally posted by Lucky
And serutan only answered the first bit! Starlifter corrected the middle bit and you appended the last bit! :rolleyes:

Anyone of you, just ask a question!!!
:D

Such impatience! :crazyeye:

OK, here's a question to root out the old farts in the forum:

What was the original mass storage device for the TRS-80
Model 1 computer?

Cassette tape drive.

Originally posted by starlifter
Cassette tape drive.

Which worked about 1 time in 3.
Your turn, SL

OK, here's one:

Define at least 9 of the 10 the following computer acronyms... if there is ambiguity, then cite your soure (or provide the hyperlink):

1. GNU
2. CD-RW
3. WORM (as in "WORM Drive")
4. bit
5. QBASIC
6. DRDOS
7. NT
8. CORE (a hacking group name)
9. VBA
10. RAM

Originally posted by starlifter
OK, here's one:

Define at least 9 of the 10 the following computer acronyms... if there is ambiguity, then cite your soure (or provide the hyperlink):

1. GNU
2. CD-RW
3. WORM (as in "WORM Drive")
4. bit
5. QBASIC
6. DRDOS
7. NT
8. CORE (a hacking group name)
9. VBA
10. RAM

1. GNU is Not Unix (Infinite Regression Alert!)
2. Compact Disk - Read/Write
3. Write Once, Read Many.
4. BInary digiT
5. Quick Basic
6. Digital Research Disk Operating System.
7. New Technology (cough, cough)
8. Crackers from OREgon.
9. Visual Basic for Applications (out, foul demons!)
10. Random Access Memory.

I've always wondered whether anyone would remember what "modem" stands for...

Anyone?

R.III

MoDem - Modulator/Demodulator IIRC, since the analogue signals need to me modulated/demodulated into digital data for the computer to understand (so there's no such thing as an ISDN-Modem since the data already is digital)
But we're jumping the queue here :D it looks like it's serutan's turn, although I always thought that NT stood for "Nice Try"

Nice job, Serutan.

8. CORE is Challenge Of Reverse Engineering (Crackers from OREgon may be one, but I've not heard of it personally ;).


You're up!

Originally posted by starlifter

8. CORE is Challenge Of Reverse Engineering (Crackers from OREgon may be one, but I've not heard of it personally ;).


I hadn't heard of it either. :crazyeye:

The question:

What are RLL and MFM (Description, not spelling out the
acronym) ?

RLL / MFM describes a certain harddisk drive types, which were used in the early PCs.
RLL=run length limited: is the "newer" encoding algorithm to store data, that enables faster access and increases also the capacity of the drive.
MFM=modified frequency modulation: was the "older" encoding scheme for harddisks but is still used for floppy disks.
:D

Originally posted by Lucky
RLL / MFM describes a certain harddisk drive types, which were used in the early PCs.
RLL=run length limited: is the "newer" encoding algorithm to store data, that enables faster access and increases also the capacity of the drive.
MFM=modified frequency modulation: was the "older" encoding scheme for harddisks but is still used for floppy disks.
:D


Yup. Fire when ready.

Ok, here goes again:

Describe the OSI network reference model (all layers)! Is it the correct model for the networks (e.g. internet) of today? If not, which model is and what are the differences?
:D

Originally posted by Lucky
Ok, here goes again:

Describe the OSI network reference model (all layers)! Is it the correct model for the

networks (e.g. internet) of today? If not, which model is and what are the differences?
:D

The layers (from the ISO site) are (descriptions are
fuzzy memories of networking class):

1. Physical layer
-- The actual hardware.

2 Data link layer
-- More or less the driver software for the HW.

3 Network layer
-- The protocol S/W

4 Transport layer
-- Interface between O/S and higher levels.

5 Session layer
-- More or less a UNIX socket.

6 Presentation layer
-- Interface between socket & user S/W.

7 Application layer
-- User application.

OSI is not the current Internet model. Although a nice abstraction, in practice a literal

implementation would be too
cumbersome (too many layers, too much overhead).

The current model is 1973's TCP/IP. It has (IIRC) 4 layers,
which (again IIRC) maps the following way:

TCP/IP level 1 maps to OSI level 1.
TCP/IP level 2 maps to OSI levels 2-4.
TCP/IP level 3 maps to OSI level 5-6.
TCP/IP level 4 maps to OSI level 7.

Correct and complete! :goodjob:

Continue please.
:D

Why are computer errors called "bugs"?

A long time ago, an early computer was malfunctioning. When they took it apart to figure out what went wrong, it turned out that a moth was causing the problem... it was a removed, but the the discussion about the insect in the machine stuck... and instead of moth or insect, they referred to it as a bug in the machine. It came to mean any general glitch in the hardware of the era (1940's). As hardware became more reliable, more and more glitches originated in the analogue wiring, and later in the digital software.... and today, it usually refers to a glitch (or unintended error) in software.

:)

As I remember it, the computer was ENIAC, and the moth
had shorted out a rack of vacuum tubes.

Tag, you're It!

You are probably right... I was not 100% sure about it, as I didn't take time to look it up :eek: ....


Hmmm.... What is the difference between USB 1.xx and the fairly new USB 2.xx? What are the approximate data speeds of each?

HINT: USB 2.xx is much faster than USB 1.xx. PS, You can look up things in this thread (e.g., you don't have to know it from memory ;) ).

OK, so no one wants to talk about USB 2.0, and since 48 hours is up, time for an anwer and a new question ;).

Answer:

USB 2.0 runs at speeds 40 times more than that of USB 1.1. USB 2.0 includes everything that USB 1.1 offers and adds a high-speed mode, which runs at 480Mbps. USB 1.1 supports two speed modes: 1.5 and 12Mbps whereas USB 2.0 has three of them: 1.5, 12 and 480Mbps. USB 2.0 also uses the same USB 1.1 compliant cables to connect high-speed devices. However, classic USB hubs will slow down USB 2.0 devices. In addition, a USB 2.0 host controller is required to enable the high-speed connection with a USB 2.0 device. Plugging a USB 1.1 device to a USB 2.0 hub is okay, but connecting a USB 2.0 device to a USB 1.1 hub is prohibited. USB 1.1 devices still operate at 12Mbps at full-speed and 1.5Mbps at low-speed on a USB 2.0 bus. Even though USB 1.1 devices won?t run any faster, they can work alongside of USB 2.0 devices on the same bus.

SOURCE: http://www.everythingusb.com/usb2/faq.htm



New Question:

What is the basic data transfer speed of a 1X CD ROM? (either KB or Kb)

I think it´s 150kBytes per second. :yeah:

At least my 4.4X old SCSI CD-ROM makes 660kB, so that must be it.
:D

Right!

150,000 bytes/sec :)

You're up, Mr. Lucky!

Hmm, again, let me think. :enlighten

How about this:
What was the reason for the crash of the first flight of the Ariane V rocket?

It was a computer error, of course, but what exactly?
:D

Originally posted by Lucky
Hmm, again, let me think. :enlighten

How about this:
What was the reason for the crash of the first flight of the Ariane V rocket?

It was a computer error, of course, but what exactly?
:D

The Ariane V computers were loaded with Ariane IV software!
Not even the great and glorious :rolleyes: Ada language could
deal with that!

Strictly speaking, this was human error, even though the
error manifested itself in the computer system.
Remeber GIGO!!!

Hmm, yes and no. They used the older IV software but reworked it. They forgot to take out a few unneccessary steps. :eek:

BUT what was the computer error that lead to the desaster?

It was something every programmer has experienced at least once.
:D

Originally posted by Lucky
Hmm, yes and no. They used the older IV software but reworked it. They forgot to take out a few unneccessary steps. :eek:

It was something every programmer has experienced at least once.
:D

Must've been a cut-and-paste error then. The problem (IIRC) was that the S/W was reacting to sensor readings as if it were in
an Ariane IV instead of a V, and in IV terms, the data indicated
a situation that required self-destruct or some such.

Yes, that is correct, BUT not the actual computer program error! :p

The actual mistake was an overflow error when converting the altitude data from float to integer. It worked in the Ariane IV because it was not as high as the V in the same time.

So OVERFLOW ERROR, was what I wanted to hear. :yeah:

Go on anyway!
:D

OK, continuing in a jugular vein:

Why did Mariner 2 (First probe to Venus) fail?

Mariner 1 failed cause it strayed off the safe flight corridor on it's approach to Venus. Mariner 2's problems focused mainly on overheating issues but then contact was eventually lost. (Hey, back then computers normally required air conditioning, so it should have been expected.)

Yes, but there was a specific error that cause Mariner 2 to
lose contact. Hint: it was software related, and it can't
happen today.

The paper in the punched-hole-card-reader burned?

Well, they probably did use paper tape, but the error I am referring to was in actual code. Again, it wouldn't happen
today (and *not* because the language doesn't exist
anymore).

What I was looking for was a FORTRAN DO loop syntax
error. The compilers of that time didn't abort on a syntax
error, so the code built and went to Venus with bad results.
Can't happen now, since I am not aware of any compiler
that does not abort a build on a syntax error.

Cartouch Bee came closest, so it's his turn now.

Do you know what version of Fortran that was, specifically? Was it Fortran77, or was it an earlier one? I began programming in Fortran in 1979, and am curious. I have used it in autonomous aerospace vehicle navigation systems, but I have not had a role in spacecraft software of any sort.

Hi,

Sorry I have not been able to get access to the site due to DNS server problems with the recent changes with telefragged servers. Even though Serutan passed, this on to me I may not be able to get access again, so Serutan, please take another go, I'm pretty sure you will make a better question than I would. ;) Besides, I don't think I hit the mark on the question.

As for the FORTRAN version, I'm pretty sure that back then, that with programming by punch cards that it was a lot of trial and error/testing. ( I guess this error was not caught! Might have actually been a hardware error though in this case but I don't have any facts to substantiate the claim.) Definitely had no precomplier to help in debugging (Some systems produce Punched tape from the cards but I'm sure that was not the process on this system.). Oh, I've did some programming of FORTRAN on punch cards so it is not really a guess cause even in later years this sort of thing was happening and precompilers were implemented to reduce codeing errors. :)

CB

How I do remember the days of punch card programs, and batch runs on the IBM 360 and Vax 11/780. After thinking about it like I should have, I'm sure the problem was not in the Fortran spec, but completely a compiler issue. Ours would reject on pass#1 based on syntax errors, so I never had experience with compilers that allowed faulty code to execute. APL would do that, but it was an interpreted interactive language.... but when it hit a bad syntax, even that would be identified and execution halted. It boggles my mind that at least a two-pass compiler did not process all code, even if the testers did not do their job and generate test cases to exercise all sections, no matter how obscure, of the source code.

:)

I actually understood some of that! Lol, I hope to be able grok all that stuff, one of these days...when I grow up ;)

Originally posted by starlifter
How I do remember the days of punch card programs, and batch runs on the IBM 360 and Vax 11/780. After thinking about it like I should have, I'm sure the problem was not in the Fortran spec, but completely a compiler issue.
:)

Absolutely. In 1961 (when this S/W would have been written), even Fortran IV was a figment of the imagination. Also,
compilers had only existed for 5 or so years at this time...
I suspect (but cannot cite evidence) that this probably helped
trigger development of the multpass compiler.

Well, no activity for more than 48 hours, so I'll ask a question.

Name a stable MS operating system. No wait. Both and oxymoron "Operating System" & MS, and reference to the word "stable".


OK, hmmmm. Let's see.

Hard drives. What is the difference in a "primary" hard drive and a "secondary", with regard to the BIOS in a PC?

And what is the difference in a "master" and a "slave"? In regards to hard drives. Computer hard disk drives, that is. :D

Hmm, not sure how much info you want! :rolleyes:

Primary: The drive, usually assigned to the letter C: by the BIOS, where it will look for an operating system. Newer BIOS software allows choosing a specific drive though.
Secondary: Well, the drive the BIOS will not look for an OS. Again, a newer BIOS may be able to select several harddisks to look for an OS.

Master: The drive that has the primary connection to the IDE bus. Must be installed for that specific IDE connection to be activated.
Slave: Can only be plugged in when a master is present on that IDE connection.

Master/Slave is for IDE bus systems, but not for example for SCSI drives.
:D

Pretty close. Good enough so you get the next question, Lucky :).


But here is what I was talking about... The Primary channel is the INT 14 (interrupts are assignable, but the convention is INT 14) for the primary, in BIOS. The Primary can have a Master and Slave IDE device attached to the same interrupt.

The Secondary channel (INT 15, by default) also can have a master and secondary device attached, giving a total 4 IDE devices on an average system.

The devices are usually hard drives, but CD ROMS, CD RWs and even lots of less-common devices like the Zip drive can hook up, though each device must be set as master or slave.


You can also add extra cards, with tertiary and quadrenary (3rd and 4th) IDE channels, each supporting another master and slave.

If you want more than 4 total IDE devices (e.g, hard drives, CD ROM/RWs, Zips, etc.), then you need to cough up more interrupts, and (unless you have a special motherboard) need to add a $40 IDE card.

Your question, Lucky!

Sorry about the delay, I might get a few serious flooding problems the next days, so that is a real concern right now. :eek:

Oh and starlifter, I thought we shouldn´t be that technical. ;) :lol:

Question:
What is the common max. length of the following cable types?
USB -
10BaseT (10Mbit ethernet, twisted pair, Cat5) -
100BaseT -
Firewire (IEEE-1394) -
SCSI -
Ultra SCSI, Wide SCSI, UW-SCSI -
Ultra2 SCSI, U2W-SCSI, Ultra3 SCSI -
RS232 (serial port, 9600baud) -

For all cables just the most basic industry standard.
:D

Sorry about the delay, I might get a few serious flooding problems the next days, so that is a real concern right now.

Oh and starlifter, I thought we shouldn´t be that technical.
Hope you have a boat or some golashes! The answer just sounded techincal... it is just the very basic, but confusing, way that IDE ATAPI drives work (e.g, 4 on most machines.. 2 on each interrupt, a master & slave, and a Primary... these determine the drive lettering that some people have discussed in other posts lately, and should be understood by people adding a new hard drive, as some have recently posted).

About the question, I'll wait a day or two to give someone else a chance, since I already know most of those quite well ;).

Ahh.. Glad to see this thread get moving again. I was a few days from unstickying it. As for the question, I have no idea!

And good luck with the flooding Lucky!

Yeah, now if somebody would just try to answer! :rolleyes: :lol:

Come on people, this is the thread where you can search ( :eek: ) for the answers.
:D

I already knew this stuff, but wanted to give others a chance. If some types of questions we ask don't get responses, we can always ask more lively sorts of questions. But this one is excellent, though obviously (from no replies) kinda dull to most people (not dull to me, as my machines don't work right if cables are not properly sized and routed!).


by Lucky:

What is the common max. length of the following cable types?


My answers will assume single cables, not enroute signal enhancers that can extend range dramatically, like USB up to about 80 ft. This is a good reference document for people that don't know about computer cabling... great question Lucky, and it is very useful for people, too!!

:goodjob:



SCSI

The SCSI question are trick (I use SCSI a lot, even to write this!). Cable length is not a function of those terms, as phrased.

Ultra = 50 pin cable (assuming internal) (8-bit devices)
Ultra Wide = 68 pin cable (16-bit devices)
Ultra2 SCSI, U2W-SCSI, Ultra3 SCSI - LVD

SCSI Cable Length is a function of transmission method (the send/acknowledge turnaround), and waveform. The faster (in MHz) the signal, the shorter the cable.

These are total cable lengths, from adapter to device (or device to device if adapter in middle):

Non-Fast devices (basically SCSI-1, 5MHz): 6 meters (19.7 feet)
Fast devices (e.g., SCSI-2, 10MHz) - 3 m, 9.8 feet)
Ultra (20MHz) - 1.5m (4.9 ft)
LVD devices (e.g., U2W) - 12m (39.4ft) , but can change, based on characteristic line impedence.

EXTRA CREDIT:
Any SCSI Differential device = 27m (88ft) ... but conservatively used at 25m (82ft).


OTHER

USB - Trick question (more than one std answer)- Full speed (12 mbps) = 3 meters (16 feet); 1.5 mbps = 3m.
10BaseT (10Mbit ethernet, twisted pair, Cat5) - 100 meters
100BaseT - 100 meters
Firewire (IEEE-1394) - Trick question (depends on cable type). Common 28 AWG = 4.5 meters, but 24 AWG = 10m, and Optical = 700m.
RS232 (old, slow serial port: 9600baud) - 15 m, 50 ft.

EXTRA CREDIT...

RS232 (Normal Serial, DTE: 64,0000 bits/s) - 3 m, 10 ft.
Parallel Cable (Old Centronics) - 15 feet (9 is safer!)
Parallel Cable (IEEE-1284) - 30 feet in length (go short for data reliability!)




LOL, you should see the wiring jobs I do with computer stuff... I almost always use the full limits of everything, except Optical, that you mentioned above ;).

Hmm, not quite, but very good nonetheless. :yeah:

USB 12mbps should be 5m.

The rest is more or less correct, go on!
:D

Ah, you're right, Lucky! I typed 3m twice :blush: .

OK, with all the avatar creating and editing by CFC members lately, here is a timely one. It is multi-part, but pretty easy.

What is advantages & disadvanatages to using the following formats for an avatar: JPEG, GIF, BMP, TIFF PSD. Also, which are lossless and which are lossy? Which is generally best for graphics & cartoons? Which is generally best for natural life? Which can have transparant background?

And one more part: you must also list at least 5 downloadable graphics editing programs, rank them, give your short opinion (1 or 2 lines) on each, and provide their URLs.


---> Remember, this 48-hour thread allows you to research and use anything to help you out (even other people)!

I'll give this a try first without research....that comes when I know I'm wrong.

What is advantages & disadvanatages to using the following formats for an avatar: JPEG, GIF, BMP, TIFF PSD

JPEG is very good at cutting down on a picture's file size but is not that good at preserving some details. GIF also cuts down file size but not as much as JPEG, it retains more detail and can have transparency. BMP has several different types which can hold differrent amounts of colors which are: 24-bit Bitmap, 16 color Bitmap, 256 color Bitmap, and Monochrome Bitmap. Generally BMP are large and don't lose color unless you save it in a type that doesn't support that many colors. Don't know about the other two formats there.

Also, which are lossless and which are lossy?

In my experince if you use the right type BMP don't are lossless, GIF are lossy but not much, and JPEG can be pretty lossy at times.

Which is generally best for graphics & cartoons?

Don't Know.

Which is generally best for natural life?

Don't Know, not sure what you are asking here, please specify.

Which can have transparant background?

The GIF can have a transparent background.(Which is why so many avatars are in GIF format!)

For the graphics programs, I'll get back to you on that.;)

Nice work, King of Camelot! I'll wait a little longer for you to finish. The Natural comment refers to "real life" images, as opposed to typical computer generated, or animated, images. :)

I think you have jpeg and gif backwards, there. gifs only support 8-bit color, however, they do support layers, thus they can be transparent, and animated. jpegs are compressed, but can support 24-bit color. bmps are uncompressed, lossless, and are pretty much limited only by hardware. huge files are possible. tiff is another true-color lossless format. i could look the other up, but i'm just answerin off the tippy top of my head. many web graphics are goin ta png, now, it's a highly compressed open algorythim. gif has been been attacked by lawyers, and jpeg has a patent claim pending...

Some one else can finish it off, starlifter, because I can't find stuff on TIFF although I have heard of it so I am at a stomp.

What is advantages & disadvanatages to using the following formats for an avatar: JPEG, GIF, BMP, TIFF PSD

JPEG - Lossy, true color (16.7 million), best in natural life (not straight edges & same-colored areas). Variable compression (small size/poorer quality to larger size/higher quality). Can be interlaced (aka "progressive").

GIF - Lossless (in detail), but can be lossy in color shifts because of its small palette (256 colors), best for most graphics, cartoons, things with continious stretches of the same exact color (they will compress more). Can have transparant background, and can be interlaced (aka "progressive"). The GIF89a standard allows animations, text blocks, and extensions.

BMP - Not compressed; Normally 256 color palette, but some software has options for 16 bit and 24 bit in addition to 8 bit color. Best for graphics at 256 color. At True Color (24 bit, 16.7 million), BMP will store a lossless image with exact color... but the file is huge, and generally not suitable for websites and internet transfer due to large size.

TIFF - Several companies developed the Tagged Image Format (including Aldus and Silicon Graphics) to be the ultimate image file format. It is lossless, and true color, and has many ways of compression. It can actually support up to 48 bit color (true color is only 24 bit). A TIFF good for archiving an exact copy of the work, but while it is smaller than the BMP, it is generally larger than GIF and JPEG (unless using one of the newest experimental TIFF compression formats). I typically save edits in TIFF, and then convert them to GIF or JPEG when the result is done. Future re-editing is done from the TIFF, not JPEG and generally not the GIF.


PSD - Photoshop Document. This is the ultimate format if you use high end editing software, since it can store channels, layers, and lots more information than other formats. It is lossless and exact color, naturally. And it is big. Many programs cannot read it, and PSD is not good for Web/Internet usage... but excellent (better than TIFF) for high end editing and use.



Also, which are lossless and which are lossy?
The bit battern of the image is lossless in .BMP and .GIF, but the colors may be altered (approximated), depending on color depth selected, # of original colors, palette transform, method, the pallet itself (e.g., windows standard, netscape standard, optmization method, etc.).

Which is generally best for graphics & cartoons?
GIFs. Typical graphics are usually limited in colors (GIFs are limited to max of 256), and the actual bit pattern is lossless. The color may be shifted (see prior answer).


Which is generally best for natural life?
JPEG, since it uses 24bit color, and a cosine transform to approximate what looks "best" to the human eye.


Which can have transparent background?
GIFs.



To clarify some of Piny's answers, JPEGs are always 24-bit color. Layers are not what gives transparancy and animation. Animation is simply consecutive images stored in one file, according to the GIF89a specification. Transparancy is setting a particular color (the "background color") to "transparant", which means the image's pixels of that color are not rendered when displayed, and whatever is underneath shows through. There is much development in the world of graphic standards, but the problem in the end for any "latest, greatest" thing is widespread compatibility. GIF and JPEG are no longer the absolute best for web use, but they are the most universal and compatible!



Well, King of Camelot... your question! :goodjob:

What is considered the first Personal Computer? What year was it created in and who(company) created it?

The Altair, a kit computer, debuted in 1975. The company
was in Albuquerque, IMSV ?

You got everything but the company name. I will give the answer tomorrow.

The company was MITS

Good, job Serutan! I was gonna give the answer now that I'm back from school, but you already have it....so, your turn.:D

What program was used to test whether or not the
Data General MV10000 worked while it was being developed?

How about a revival of this thread with a new question?
Obviously nobody can answer the one above, or nobody wants to.
:D

Fine by me. BTW, the answer was "adventure". Got
it from the book "Soul of a New Machine".

So go ahead, Lucky.

Me??? :eek:

Actually I meant you to post a new question, but oh well, here goes:

What do SISD, SIMD, MISD, MIMD stand for? They are part of the computer characterization by FLYNN. Describe them a bit!
:D