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Caleb Kraft
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need?
Caleb Kraft   11/25/2013 5:03:18 PM
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I don't know that they NEED to. I think everyone could benefit from being able to solder though, even people who aren't in the engineering world. Well, except for wizards they can just do whatever they want.

Duane Benson
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Is it becoming more common?
Duane Benson   11/25/2013 5:03:50 PM
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I'm curious. Hobby electronics has exploded over the last few years. Has any of that been connected up with professional engineering? Like, do engineers-by-day become hobbyists after hours? If so, has that necessitated an increase in soldering skills?

Caleb Kraft
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Re: Is it becoming more common?
Caleb Kraft   11/25/2013 5:06:46 PM
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I think there are electronics hobbyists from all walks of life, especially now that we have fairly easy-entry things like arduino. I've known several engineers who have enjoyed the hobby as well.

Duane Benson
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Re: Is it becoming more common?
Duane Benson   11/25/2013 5:24:23 PM
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Caleb - looking at engineers like Jason Kridner (Ti Beaglebone camer and other projects) and Jeff Keyzer (Geiger counter, GHz Amps & such), I'd have to agree with you that there are engineers who still enjoy creating when outside of the corporate walls.

Duane Benson
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Other lost skills coming back
Duane Benson   11/25/2013 5:20:35 PM
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Many years ago, in a galaxy, pretty much right here, I'd expect to fix just about any electronic device of mine that failed. Somewhere along the years, component level repair became too expensive, too complex and in general, impractical.

However, along with the recent hobby re-revolution, that's been changing. In the last year, I've successfully performed component level repair on an LCD monitor, a gaming mouse, a digital camera and a few other similarly complex items. A decade ago, that would have been unthinkable.

Has anyone else found home electronics repair viable again?

Caleb Kraft
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Re: Other lost skills coming back
Caleb Kraft   11/25/2013 5:28:32 PM
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part of why some of them are repairable for me is that there are great tutorials out there. I've replaced capacitors on a couple TVs that I never would have found on my own, but they were documented issues. 

Duane Benson
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Re: Other lost skills coming back
Duane Benson   11/25/2013 9:18:02 PM
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Caleb - "...that I never would have found on my own, but they were documented issues."

It pretty much seems like if I've had a device fail, someone else has had the same thing fail and has posted some information on it online.

Doug_S
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Re: Other lost skills coming back
Doug_S   11/25/2013 9:00:15 PM
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Why do you say it is becoming viable again?  What is it about the failures of these recent devices that left you able to diagnose/repair them, versus the failures of devices a decade ago that you couldn't/didn't?

Duane Benson
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Re: Other lost skills coming back
Duane Benson   11/25/2013 9:16:20 PM
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Doug_S - It's incredibly easy to find schematics or other documentation for just about anything online. There are also tutorials for quite a few broken things. And, more parts seem to be available.

David Ashton
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Re: Other lost skills coming back
David Ashton   11/26/2013 3:39:35 AM
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@Duane.... "It's incredibly easy to find schematics or other documentation"  I wouldn't quite go along with that, there are just so many different makes and models of things around these days.   But in many ways it is easier for the hobbyist or garage repair-guy to get info than it used to be.  And the number of people who share their tricks and fixes online is great.    

I have found that often the difficulty is getting the right parts - I recall a plasma TV that needed some electrolytics (as usual in TVs) but I could NOT get the right rating and the right form factor anywhere.  Eventual;ly I had to junk it.

I also fixed a cordless drill recently - I could not find info but traced a dry joint.  But reckoning my time at what I get paid at work, I could have probably bought a couple of new drills....  which is why no one does it commercially.

Caleb Kraft
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Re: Other lost skills coming back
Caleb Kraft   11/26/2013 9:31:35 AM
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complexity is a killer here. On older circuits, I could visually trace things. On newer circuits, I have no idea what is going on in all the layers of the board and the more complex power routing with which I am not educated. 

Crusty1
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Re: Other lost skills coming back
Crusty1   11/26/2013 3:13:45 AM
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Hi Duane: I agree I have started to repair consumer products again. There is so much more information available on the net now, such as tear downs and repair videos.

My daughters Canon Ixius camera had a problem with it's zoom switch, a similar wreck from e-bay produced the part, no soldering, but I did need the other skill I have, which is watch repair, try taking a ladies cocktail dress watch apart, to see how small they got mechanical watches.

I think just like well priced mechanical watches much consumer electronics have become very modular, so breaking down and reassembly has become easier.

That is apart from getting a seam welded case open without cosmetic damage, anyone got a tip for this?

Crusty1
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Re: Other lost skills coming back
Crusty1   11/26/2013 5:14:37 AM
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Hi Duane: I agree I have started to repair consumer products again. There is so much more information available on the net now, such as tear downs and repair videos.

My daughters Canon Ixius camera had a problem with it's zoom switch, a similar wreck from e-bay produced the part, no soldering, but I did need the other skill I have, which is watch repair, try taking a ladies cocktail dress watch apart, to see how small they got mechanical watches.

I think just like well priced mechanical watches much consumer electronics have become very modular, so breaking down and reassembly has become easier.

That is apart from getting a seam welded case open without cosmetic damage, anyone got a tip for this?

Crusty1
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Re: Other lost skills coming back
Crusty1   11/26/2013 5:17:26 AM
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oops seemed to get posted a number of times sorry

Duane Benson
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Re: Other lost skills coming back
Duane Benson   11/26/2013 11:39:18 AM
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Crusty - Since I rarely throw things away, I've been having a bit of a field day fixing up broken items I've had buried in my garage. I can't help you with the case though. Mechanical things are not my forte.

zeeglen
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Re: Other lost skills coming back
zeeglen   11/26/2013 12:00:20 PM
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Another skill is reading resistor color code without needing to look it up on wikipedia, but sometimes it can be misleading.  Some manufacturers are not overly caring about the quality of the paints they use, often it can be difficult to distinguish between brown, red, and orange even when the resistor body color is light such as beige.

I recently ordered some 4K99 1% resistors made by KOA Speer, when they arrived I had to put one on the ohmeter to verify the value - its colors were green white white brown brown which indicates 5K99 1%.  Then I realized that the first band was actually yellow but transparent to the blue body color, which converted it visually to green.  An almost gotcha.

Duane Benson
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Re: Other lost skills coming back
Duane Benson   11/26/2013 12:53:54 PM
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Zeeglen - For some reason, I still (and always have) need to look up and double check blue, grey and white. Those three never managed to stick in my head.

David Ashton
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Re: Other lost skills coming back
David Ashton   11/26/2013 2:55:52 PM
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@Duane - "...blue, grey and white....never managed to stick in my head."

I have the same problem - I thought about it once and I think it is because those colours are the least used in the common E6 series of values - blue and grey are only used in 68, and white not at all.  And really in a lot of cases you only see "E3" values - 10,22,47.  I'd do an analysis of the frequency of use of the colours in E12 but I have to get to work :-(

There's a nice graphic here showing all the E series and how they overlap:

http://www.logwell.com/tech/components/resistor_values.html

David Ashton
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Re: Other lost skills coming back
David Ashton   11/27/2013 4:07:53 AM
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@Duane....Well having got back from work I did just that and got the following.

The E columns indicate the frequency of use of the colours

E3 is the frequency of colors used in the basic E3 values (10,22,47)

E3M is as E3 but with one added for each time a colour is used as a common multiplier (ie black to green) - I thought I would do this as we use these colours as much as the value colours.

And the same for the E6 & E12 series, with and without multipliers.

White is definitely the least used and there is a bias towards the lower colors. but apart from white there's not much in it.

HOWEVER - if you look at E3M, which comprises the most frequently used values, your difficult colours are the ones with Zeros, Duane.  I rest my case!

 
Color E3 E3M E6 E6M E12 E12M
Black 0 1 2 1 2 1 2
Brown 1 1 2 2 3 4 5
Red  2 2 3 2 3 5 6
Orange 3 0 1 2 3 3 4
Yellow 4 1 2 1 2 1 2
Green 5 0 1 1 2 2 3
Blue 6 0 0 1 1 2 2
Violet 7 1 1 1 1 2 2
Grey 8 0 0 1 1 3 3
White 9 0 0 0 0 1 1


Duane Benson
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Re: Other lost skills coming back
Duane Benson   11/27/2013 3:45:30 PM
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David - Blue sometimes makes me double check too, but Violet is ingreained because for some reason, 47K is a very common value for me.

David Ashton
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Re: Other lost skills coming back
David Ashton   11/27/2013 4:04:54 PM
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@Duane - "Violet is ingreained because for some reason, 47K is a very common value for me."

Exactly my point - a lot of people only use 10 / 22 / 47 values - for things like pullups where the exact value is not important you'd get away with just stocking those values.   Although (theoretically) E3 values have a 50% tolerance and are no longer used, their values live on as the most used resistors

zeeglen
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Re: Other lost skills coming back
zeeglen   11/27/2013 9:37:49 AM
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For some reason, I still (and always have) need to look up and double check blue, grey and white. Those three never managed to stick in my head.
@duane   Just think of the last 4 words of that well-known "bad boys" mnemonic...

Duane Benson
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Re: Other lost skills coming back
Duane Benson   11/27/2013 12:47:18 PM
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Zeeglen - The mnemonic apparently isn't well-enough know, because I don't know it. Of course, that's more a stament about my brain than about the mnemonic.

zeeglen
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Re: Other lost skills coming back
zeeglen   11/27/2013 4:30:33 PM
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@Duane

http://en.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics

and look at the last entry

David Ashton
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Soldering.....
David Ashton   11/26/2013 3:48:59 AM
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Duane... "my personal opinion is that electronics engineers should know how to solder."   Leave aside the engineers - MANUFACTURERS should know how to solder.  One of my pet peeves is the use of wave soldering on parts like power sockets, screw terminals, connectors etc.  It's never enough.  The number of things I've repaired by resoldering parts like this is unreal.  ANY component which gets mechanical stress needs proper soldering, with a bit of meat on the joint.   I don;t know much about soldering machines, but they always seem to get it wrong.

Duane Benson
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Re: Soldering.....
Duane Benson   11/26/2013 4:09:56 AM
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David - "MANUFACTURERS should know how to solder"

I second that! More tah once, my repair has simply been to touch up a solder joint.

There really is an art to solder machines - surface mount or though hole. Proper application of flux with a wave solder or selective solder can have a big effect. The speed through the wave can. With surface mount reflow, there are a very large number of parameters to get right.

What amazes me is how many devices have ambysmal quality hand solder joints of thru-hole parts. They look like they could have been built in the 1980's. Most power supplies I've opened up - wall or car - seem to fall into this workmanship category.

Ron Neale
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Re: Soldering.....Dry Joints essential knowledge
Ron Neale   11/26/2013 6:53:38 AM
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Duane; I think the point you make when you run your soldering iron over all the joints is although it might be useful to know how to solder, it is even more useful and important for engineers to know exacltly what a dry joint is, why it occurs, what it looks like and the all the possible consequeces intermittent or otherwise.

I recently had a home motion detector fail. The symptoms: the device detected motion turned on and would not turn off unless reset at the mains. Suspected the timer and light level variable resitors rotated them about with no joy. Although a relative low cost item I decided to do my own tear-down. After solving the puzzle of getting it apart inside were a mixed collection of discrete components, ICs and a few little mystery boxes, Some of the little little PC boards had evidence of poor soldering, oxide gray-white color! I scraped at those joints that were visible and soon the detector was fully operational.  A quick dab with a hot soldering iron and flux on each joint and the device was soon back in place working. Money saved about £20 ($30) fun and satisfaction value £or$ priceless.

Crusty1
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Re: Soldering.....Dry Joints essential knowledge
Crusty1   11/26/2013 10:04:33 AM
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@Ron Neal: I think I can add hot joints to this.

I have come across a number of power packs where the main resistor was not provided with a sufficient heat sinked, or the copper traces were too small for the thermal energy disipated. You end up with a dry joint in the end, but from thermal stress.

One more reason for soldering and repair skills, is in a companies returns department. To get the best quality control a returns department needs to actually tear down the faulty items and feed problems found back into the production cycle. On a number of third part quality audits I have undertaken, the returns process and how it feeds into the production cycle has often been the biggest audit failure.

elizabethsimon
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Re: Soldering.....Dry Joints essential knowledge
elizabethsimon   11/26/2013 1:14:47 PM
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@ Crusty: A good point about the failure of solder joints from thermal stress. I've repaired several older Amatuer Radio tranceivers. In almost all cases, the repair was to re-solder a power component in either the power amp or power supply.


The other failure that I've seen frequently is a solder joint failing due to repeated mechanical stress. Power jacks seem to be especially suseptible to this....

 

zeeglen
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Re: Soldering.....Dry Joints essential knowledge
zeeglen   11/26/2013 1:27:33 PM
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@elizabeth  The other failure that I've seen frequently is a solder joint failing due to repeated mechanical stress.

As in cheap equipment that depends entirely on solder to hold a volume control in place.  Guaranteed to last just beyond the warranty period.


Sometimes I think dry joints from hot resistors are just another way to ensure eventual failure and future sales.


betajet
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Re: Soldering.....Dry Joints essential knowledge
betajet   11/26/2013 2:18:14 PM
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elizabethsimon said: The other failure that I've seen frequently is a solder joint failing due to repeated mechanical stress. Power jacks seem to be especially suseptible to this...


Surface-mount headphone jacks often fail too.  It's a wash as to whether the solder joint fails before the PC board traces peel off.  You really need through-hole.

Duane Benson
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Re: Soldering.....Dry Joints essential knowledge
Duane Benson   11/26/2013 11:43:44 AM
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Ron - "it is even more useful and important for engineers to know exacltly what a dry joint is, why it occurs, what it looks like and the all the possible consequeces intermittent or otherwise"

So very true. It's quite far from just a matter of turning on an iron and going. Oxidation, surface type, thermal mass - all of those things come in to play.

Fortunately, with a bit of awareness, it can become second nature.

zeeglen
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Breadboarding
zeeglen   11/26/2013 9:37:49 AM
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Solderless breadboards are OK for many circuit designs, but when dealing with RF or low-level analog the only sure breadboard is copperclad.  This requires soldering skills.

Denis.Giri
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it never was...
Denis.Giri   11/28/2013 3:32:53 AM
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"Like so many things in the modern world, hand-soldering is no longer a required skill"

Like so many things in the modern world that tend to get replaced by other (better?) stuff, soldering was never required for everyone. Only for people who needed to know that skill.

Now, more than ever, we get products entirely built in a non-fixable SiP, connectors are as standard as can be, most analog systems get replaced by digital systems, and people get a status of electronic engineer for writing verilog code instead of soldering transistors on a board.

The industry evolved.

Thus, my answer to the question "What? electronic engineer cannot solder anymore?" is: "Mu. The question is wrong"

Victor Lorenzo
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Re: it never was...
Victor Lorenzo   11/28/2013 4:28:44 AM
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It all depends on what the engineer is supposed to do and what he is working on. I'm able not only to solder 4x4 mm QFN chips or 0.2mm pitch OLED connectors, I can also make near-zero tolerance pieces with a lather and work with CNC Fanuc milling machines and work with many wood tools and that makes me feel like my hands are usefull. I can imagine, conform in my mind, design and 'manufacture' 'somthing' and, at the end, see it in my hands. A now retired collegue of mine used the term 'real-engineer' (he has even more, far more, skills).

Not because of that I think my new collegues are useless or under-skilled, they have other also valuable skills, but as we need to make working prototypes that imply not only electronic but also mechanical (complex in some cases) parts we have a shorter reaction time to our customers requirements. When subcontracting the real production I know the exact amount of work required and that is an advantage.

Anyway it is sometimes disappointing to see new engineers who are almost completely unable to fix anything (even devices they have designed) or even to solder a simple wire in a cable that you need in that precise moment and you can not wait for the two/three days delivery time that buying a new one implies.

 

Duane Benson
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Re: it never was...
Duane Benson   11/28/2013 12:26:38 PM
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Dennis - You have a very good point. The industry (and world) has evolved.

A lot of people think that knowing Assembly language is dreadfully important. I used to know a bit about Assembly in a Z80, 6502, CDP1902 and 8086. However, I've long forgotten that knowledge. I just don't care about it.

I use a lot of Microchip PIC processors, but have never bothered to learn the least bit about PIC assembly. If I need more code space due to my C code, I spend an extra nickle and double my memory. If I need more performance, I'll pull up a ARM chip for the same price (or less).

I suppose we all choose our skills to hang onto. Soldering is just that chosen skill for me. I work my day job in a company that has massive pieces of incredibly cool machinery for soldering all kinds of surface mount and thru-hole parts.

Those machines do a great job and I love to watch them in operation, yet, one of my most enjoyable past times outside of work is to try to do a good job of hand soldering tiny parts.

It's probably a sickness. Maybe there's even a medical term for it: "et bonum stannum et plumbi verum amentia"

 

 

KB3001
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Re: it never was...
KB3001   11/28/2013 1:24:42 PM
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We are all inflicted Duane. I too find soldering therapeutic!

betajet
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All Students Take Calculus
betajet   11/28/2013 1:52:50 PM
Since I still solder and program in assembly language, perhaps I'm biased but here's my opinion:

1.  An expert needs to know how things work one or two (or more) levels below the level at which he or she normally works, so that misbehavior is not mysterious and things don't happen because of Magic.  Dilettantes are not subject to this restriction.

2.  An EE who cannot solder cannot build things for himself or herself.  IMO most engineers are engineers because they want to know how things work and delight in building things that work.  If I were to meet an EE who could not solder, I would wonder why that person became an EE unless there's a physical disability.

3.  A computer programmer who never learned ASM does not know how computers really work.  To me, it's a thrill to be working at the ASM level (perhaps using C as a portable ASM) because you have full control over the computer, rather than working though several layers of condoms.  To me, a computer scientist definitely needs to have mastered ASM as it's a fundamental part of the Science.  As with an EE who cannot solder, I would have misgivings hiring a computer programmer who didn't enjoy ASM and ask myself "why did this person become a computer programmer if he or she doesn't like computers?"  If you just want to be a "coder" with an operating system and an abstract interpretive language between you and the hardware, this is not necessary.  However, if you want to be an embedded programmer you'd better know ASM because a lot of the errors you see can only be understood at the machine language level.

JMO/YMMV

Duane Benson
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Re: All Students Take Calculus
Duane Benson   12/1/2013 11:49:36 PM
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Betajet - It's fair to say that I have a bad attitude about PIC assembly programming. I have studied the architecture a bit, but that's not the same thing. I really enjoy C and can get a lot more done in a lot less time. With ARM processors, I'm afraid I'll probably never allocate the time to learn assembly. Again, I'm studying the architecture a bit, but my programming will probably go no lower than C.

What's really astounding to me is that some CS graduates, I've interviewd recently, barely have any actual coding experience - assembly or otherwise. I really can't wrap my head around that one. The good candidates have done a lot of programming on their own, but in the program, more than one that I talked to had done some Java, but little else. I don't get it.

David Ashton
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Re: All Students Take Calculus
David Ashton   12/2/2013 12:47:01 AM
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@Duane - I'd agree with both you and Betajet.  I did some Assembly stuff in the good old days (8080 / Z80 etc) and since then have not done more than observe how things have gone since my job has not been in that field.  However I've recently started playing with PICAXEs (Pics with a Basic interpreter).  Lots of fun, and REALLY easy, but some limitations.   I think that having done assembler stuff in the past does help a lot with understanding how MCUs work, but I marvel at the ease with which guys like you and Caleb jump into pretty well any processor from any manufacturer using C.  I think that's the way I'd like to go.  I just need to win the Lotto and retire to get the time.....

Duane Benson
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Re: All Students Take Calculus
Duane Benson   12/15/2013 6:48:36 PM
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David; re "jumping into any processor I see"

That's probably overestimating my skill. :-)  What always seems to delay me the most is the fuse/configuration bits. PICs are notorious (at least to me) for being diffiult to get the fuse bits right on a new mode MCU. It's only something in the range of 8 - 16 settings to get, but they drive me nuts. The worst part is that it seems like the same fuse (same lable anyway) can work differently from one MCU to another otherwise closely related MCU.

As far as the useability of the C, I think MCU C tends to be a lot closer the Assembly then C on other platforms. I still have to directly manipulate the I/O registers in most cases. C obvioulsy takes care of bank switching and adds in a lot of structure, but I still think it leads to a  decent understanding of the architecture.

David Ashton
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Re: All Students Take Calculus
David Ashton   12/15/2013 7:46:24 PM
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@Duane - I have heard the PIC configuration ican be a real pig.  

I signed up for the MCU course with the ST ARM board and just got the board - so this is going to be a baptism of fire I think.  Plenty of little problems there too by all accounts.  Good thing I'm a bit of a masochist :-)

Duane Benson
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Re: All Students Take Calculus
Duane Benson   1/3/2014 6:46:40 PM
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David - How's the MCU course going?

David Ashton
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Re: All Students Take Calculus
David Ashton   1/3/2014 11:57:46 PM
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@Duane - you're not supposed to ask.....I just had 2 weeks off.....had about 10 000 things to do, of which this was about no 5000....only got about the first 2000 done so this got left on the list.......   I need one of those Round Tuit things....

betajet
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Re: All Students Take Calculus
betajet   12/2/2013 12:51:33 AM
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I agree with you about PIC machine language.  I took one look at it a long time ago and once was enough.  If you're going to have an accumulator machine, at least do something clever like the PDP-8 and have just 8 instructions (well, the 8th instruction is actually multiple micro-coded instructions, but then that's pretty clever too).

ARM is problematic.  At one time it was a RISC machine, back when "A" stood for "Acorn" but each architectural version has crammed new instructions into irregular gaps left by the previous versions so that it's now well into the realm of rococo.  If you like complex railroad timetimes with myriad footnotes, you'll love the ARM "quick reference card".

I did most of my early ASM programming in PDP-11, which was a delight.  C was designed to map easily and efficiently into PDP-11 machine language, and it shows.  Machines based on PDP-11 are generally very pleasant, such as 68000/Coldfire and TI MSP430.  For RISC machines, I really like PowerPC -- very regular and well-planned.

It sounds like you've studied enough machine language to understand what computers are doing.  Once you've done that, it's not necessary to keep programming in ASM, particularly if you can visualize what the computer is doing as you write in C.

Regarding your experience with recent CS grads -- and their lack of experience with programming unless they were doing it on their own -- I would make the following comment:  It's very time-consuming to grade programming assignments -- you can't just see if the answer is the correct number or the correct formula.  Each answer is different, so it's like grading essays.  Grading this sort of assignment takes time away from other professorial activities like publishing papers and getting research grants, so any idealistic teacher who spends his or her time doing it is not going to last long in modern academia.

That said, when I was an student I did spend at least an order of magnitude more time writing programs than what was required by classes, because I loved it and still do.  Your candidates who did lots of programming on their own likewise love it, and you should hire them because people who enjoy their jobs are generally going to do much better work.  The ones who only did programming when it was assigned will most likely treat a programming job as "just a job".

JMO/YMMV

KarlS01
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Re: All Students Take Calculus
KarlS01   12/2/2013 11:03:11 AM
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@Betajet: Thanks for pointing out the microcode(horizontal microcode?) aspect of the PDP-8 and how C maps so well.

Terminolgy is so superfical or understanding is so superficial that it is nearly impossible to discuss a new concept, but maybe the ease of mapping C to PDP-8 can help.

C structures a program into statements and compound statements delimited by curly braces. statements are either assignments or flow control using relational evaluation for the loops, switch, and if statements. 

The flow is sequential or the non-sequential target of the control statement.

That means that C can be parsed and microcode a la PDP-8 (bit significant) can be generated to execute C directly without compiling to a conventional ISA.

Just an extension of the bit significant micro code and I am having fun doing it.

betajet
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Re: All Students Take Calculus
betajet   12/2/2013 1:51:38 PM
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It's the PDP-11 that maps well from C.  The PDP-8 is a 12-bit accumulator machine with paged addressing and not a good C target.

The PDP-8 "microcoded" instructions do not use the usual meaning of the word.  The OPR (operate) instruction doesn't have the usual 9-bit operand field and insteads uses those bits for various functions like "complement accumulator" (1's complement) and "increment accumulator", but you can do multiple functions in the same instruction: "complement and increment accumulator" does both functions in sequence, giving you 2's complement.

If you're interested, there's a good description at Wikipedia.  The PDP-8 instruction set is so simple that it only takes a few minutes to learn it -- though much longer to master its tricks.  It's a fun ASM if you enjoy puzzles.  If you just want to get work done, use an architecture that maps well from C like PDP-11, 680X0, or PowerPC.

KarlS01
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Re: All Students Take Calculus
KarlS01   12/2/2013 2:23:43 PM
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@Betajet: Sorry for the error.  My contention is that the typical third stage of compile takes a nice compact intermediate language and and breaks it into so many loads, stores, and whatever else RISC is noted for,  that memory accesses are excessive and too many cycles are used.  This leads to the "memory wall" and not being able to simply clock faster to overcome the waste.  Bit significant micro code is a good way to control CPUs as well as FPGAs and embedded block RAM can be used for more registers than any RISC ever dreamed of and gets the performance benefit. 

Assembler is fun for puzzle like entertainment, but takes years to make a system.  IBM OS/360 was a great example. 



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