Art of Electronics 3rd edition? (probably the billionth time this has been asked here)

own

All a logic analyzer usually does is tell you to read your own code... after a day or so of setup and fiddling.

John

used

own

totally

Not in my cases. Sometimes it is stuff that comes off of a complicated circuit board with tons of DSPs on there and the bug could be just about anywhere. Other times it is an OEM-product with a uC on there that occasionally goes on the fritz. In fact, a Fedex truck is going to be rumbling down Highway 50 today, with one of those cases in its belly, to be diagnosed here. Maybe I will need the logic analyzer after all, maybe the DSO is enough. But that's often not the challenge. The real challenge will then be to convince the OEM supplier of my client that there is a problem and that it needs to be fixed.

--
Regards, Joerg

http://www.analogconsultants.com/

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Jay Ts wrote:

As the Plainclothes Hippie notes, he's a churchgoer. That's kinda the context where I first spotted him.

Doesn't make him unfunny. (Note that I am an anti-religion atheist.) In fact, he used to be a junkie; when his life bottomed out, he found a new crutch then rebuilt his life around his family. He's turned that into great entertainment.

My understanding is that Tek kept using their own (expensive) CCD-type memories (very fast parallel input, slow serial output) long after the rest of the industry had gone to just using commodity (cheap) SDRAMs with sufficient multiplexing to keep up with necessary data rates.

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

? :-)

Well, I wouldn't go whole-hog on that, personallly. Yes, I agree that in the design phase if you need to use a logic analyzer to figure out what the #$^% you're doing, then yes. You're supposed to design it right in the first place.

But from the Techie's point of view, if you're troubleshooting a new system, they can be quite useful for tracking down the malfunction.

Nowhere near as much fun to use as a spectrum analyzer, of course. ;-)

Cheers! Rich

When I was in the video game repair biz, they had a tool called a "signature analyzer." It was essentially a logic probe with a digital display, that was sync'd to the processor. At each test point, there was a certain "signature," or bit pattern. When you found a test point with the wrong signature, that narrowed the problem down to just a component or two.

Then again, in the video game repair biz, sometimes it was cheaper to "shotgun" a board than diagnose it. Shop time was:

Shop rates: $30.00/hr $40.00/hr if you watch $60.00/hr if you help $100.00/hr if your kid helps

But seriously, it was $30 - the rest is from a sign we had posted on the wall - (this was in the mid-1980's), it was sometimes cheaper to simply replace every chip on the board at like nineteen cents a chip, done in an hour, than to spend two hours tracking down which chip was bad.

Cheers! Rich

FWIG, the CA legislators pension fund is commingled with prison guards' pension fund. I wonder why they stuffed the prison guards pension with neat perks? Simple solution; privatize the prisons *and* the legislature, declare bankruptcy, wipe the pension funds clean, and declare the problems fixed.

I've heard of those; seemed like a good idea at the time, but it was never clear to me how you got everything synchronized up. What signal was used to indicate "begin comparison with the signature?" Just the CPU's reset line or similar?

Was it your own video game repair business, or were you working for someone? Was it pretty clear that the whole arcade-type video game business was going to be rapidly decimated due to home consoles and PCs? Or a bit of a shock?

Most malls still seem to have an arcade, but these days it seems like it's mostly older games and anything new is one of those "skill" games that dispenses tickets so you can pay $10 for a $1 stuffed animal at the front counter. Seems like 99% of new games are for consoles or PCs now -- it's only the occasional multi-player game or pinball game that makes sense for an arcade.

Williams -- who made some of the best video and pinball games of the '80s and '90s -- was entirely out of that industry by the turn of the century and now focuses entirely on casino games. Kinda sad...

---Joel

I don't begrudge him anything or anything like that, in fact I've seen some of his material, and he can be quite funny; in addition, he's "clean," which I have no problem with, it's just that every now and then he drops a little reference to Jesus or The Lord, and my inner atheist says, "Erk!" ;-)

If you nailed me down and threatened to waterboard me if I didn't tell my religion, I'd say NeoDruid. ;-)

In truth, Freedom is my Worship Word, with apologies to Mr. Roddenberry and whoever wrote that ep. ;-)

Cheers! Rich

Well, if you're talking about grade-school arithmetic, I sometimes fantasize about having a position in a classroom teaching arithmetic; I have a line about introductory algebra:

Me" "Algebra doesn't have to be scary. Algebra is just a fifty-cent word for arithmetic that's just been rearranged a bit. For example, Billy, if you have three apples and I give you two, how many apples do you have?"

Billy: "Five?"

Me: "Exactly! Now, if your Mom is about to bake a pie that needs five apples, and you only have three, how many apples do you need to go get?"

Billy? "Two?"

Me: "Congratulations! You have just done Algebra!"

Cheers! Rich

As I think back, I think I learned arithmetic before I learned to talk. I had this educational toy, which was a balance scale, with a stock of molded plastic numerals, each of a mass equal to its number times the mass of the numeral 1. IOW, the 1 weighed 1 unit (whatever they were - maybe five grams), the 2 weighed 2, and so on. They went up to 9; obviously it'd be a little difficult to work in a zero on that set. ;-) But, you'd put a 2 and a 3 on one side and a 5 on the other, and it'd balance. My vocabulary at the time was such that I called it a "number weigher." I remember sitting on the kitchen floor playing with it.

So, I guess I had an unfair advantage for the first part of my life; I was home-preschooled.

But when I got to college calculus and stuff, it was like I hit a brick wall. Admittedly, this could be blamed on the fact that all I did in college was drink, and through 12th grade, I always had my older brother and sister's books to cheat off of - suddenly, OOps!

So I dropped out. This was in 1968, when Vietnam and the draft were in full swing, so I dodged the draft by joining the Air Force. I'd been playing with electronics since I was about 7, so I was kind of a natural for a tech. :-)

Cheers! Rich

Oh yeah, those signature analyzers were sometimes worth their weight in gold.

Except today, when it's a big fat BGA that costs three-digit or is unobtanium to any repair folks because the mfg does not wish their boards to be repaired.

--
Regards, Joerg

http://www.analogconsultants.com/

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100% Gene on the writing. http:// google.com/search?q=Yangs+Comms+Trek&hl=all

...after which, you find the solder fleck causing the problem.

Take a look at an HP 5005B.

When using them to debug HP equipment you had to set a jumper to put the instrument in a debug mode. There were three inputs to the signature analyzer: start, stop, and a clock. In my experience with them they never worked very well, unless you had the exact revision firmware mentioned in the service manual in the unit under repair. Which was almost never, of course. Maybe results would have been better if you bought the service manual at the same time that you bought the equipment...

When troubleshooting digital stuff back in the 80's and early 90's I always liked the Fluke 9010 with a pod for whatever CPU you were working with. A bit more expensive, though, and they tended to make you lazy. :)

Wall Street banker: "I'll sell two of the apples, eat half an apple and the remaining half gets leveraged. If the remaining half turns out to have a worm in it and is rotten, not to worry, we'll just request a bail-out. Which should give us seven apples, two of which can be doled out as bonuses".

"Congratulations Mr.Banker! You've just earned yourself a six-figure bonus!"

Politician: "I'll eat all three apples and tell mom to bake the pie next year, using the remaining zero apples."

"Congratulations Mr.Politician! You've just earned yourself another four year term and a nice fat pension!"

--
Regards, Joerg

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I received an email from Amazon.ca that they are pre ordering them, ETA is January 2011.

Shaun

And the book is superb, worth every penny.!