Signals and Systems for Dummies

Oct 21, 2017 132 Replies

On a sunny day (Tue, 24 Oct 2017 08:41:31 -0400) it happened bitrex wrote in :

That is silly, I try to avoid libraries as much as I can, and never had a problem. It does give me in depth (you need then to study that subject) knowledge of many fields that clueless library users do not have. Also then often my code is smaller, and I can do it in asm on any micro, plus do a few tricks that others cannot.

It is a bit like taking a taxi for the masses, versus building your own specialized car. I have done it for video, for graphics, for ethernet, and for I do not even remember how many other things. It is fun. The 'square wheels' are the silly linked against the rest of the universe tinkerers, often ten times slower. And I often publish the code. Now publish yours, and let us see what you can. You have been here a while where is it? All hot air. I am with JL on this one, show your work. Quoting some book or echoing the jive by others is not good enough.

It's in C++ - what's the point of "showing work" to someone who a priori claims to dislike the whole ball game without reservation? Shall I cook a lovely steak for someone who doesn't like steak?

JL likes to say "show your work" a lot I think because he assumes everyone else also has something to prove. I definitely don't and honestly couldn't give a toss if it's judged to be evidence of competence or incompetence. Code straight ASM to the end of your days if that's what pleases you, ain't no law says you can't and if that's what you like and are good at you probably should.

Just because there are many clueless library users does not materially imply that the design of the library is clueless. You can put a high performance sports car in the hands of an abject moron and the results will be about predictable. Doesn't mean there's a thing intrinsically "wrong" with the car.

It sounds like your characteristic is spot on here. And the guy is so clueless that he is /proud/ of this attitude!

Such people can have a lot of fun as hobbyists, but are a true pain to anyone involved in real work.

You're making a mountain out of a molehill, you know that.

Yeah some of us aren't retired and optimistically will have to work for real money with many other people for the better part of the next 30 years if we don't wanna end up one of those "entitlement" queens folks seem to like to crow on about.

On a sunny day (Tue, 24 Oct 2017 10:04:49 -0400) it happened bitrex wrote in :

Yea happens every day:

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There was a Tesla of the road on fire not far from here a while back too.

On a sunny day (Tue, 24 Oct 2017 09:58:00 -0400) it happened bitrex wrote in :

Strowman

On a sunny day (Tue, 24 Oct 2017 16:25:23 +0200) it happened David Brown wrote in :

Nope, I expose incompetence. I am not a hobbyist, at least now I am retired so maybe now I am, I bring probably more years experience in more fields than most of you.

To quote Bob Dylan: 'He who is not busy being born is busy dying'

Not worth spending time arguing with you softies reciting the same crap over and over again, bloat is and bloat will be until the mushrooms clean it out. Dinner time, mushrooms. mmmmm :-) later.

To be fair though often on embedded systems wheel-reinvention isn't always a bad idea; I am "guilty" of the same thing myself sometimes because the standard libs are geared toward non-realtime applications on fast processors with large amounts of memory that's easy to dynamically allocate.

There's such a wide variety of microcontrollers and microprocessors though it would be impossible to write libs that pleased everyone all of the time for every application.

However I don't see any reason to do it in asm in 2k17. Even 8 bit uPs are not 6502s and 8051s anymore; they're very sophisticated and powerful devices by comparison and can do a lot more with similar clock speeds and memory resources than their ancestors could. For a lot of tasks it doesn't make any sense to treat them much differently than you would any other processor; write the code on a desktop machine in a generic HLL (keeping in mind your constraints on code size and memory allocation) and simply port it over as you would if you were going from say PowerPC to x86. If it works fine for the application with no further modifications other than the changes specific to the architecture, great.

If it doesn't you profile to find the bottleneck and can rewrite that section to be tighter or with a custom algorithm or even in straight asm if that's what you need.

Hey, you said "if it has a ++ in it it's a crime against humanity." Ok, well I wouldn't to make you a voyeur to crimes against humanity, that's not a nice thing to do.

A discussion group needs things to discuss, beyond existential planetary disasters. And designing circuits is fun. You might look up that unfamiliar word, "fun."

Making a good sine wave from a cheap ARM is not a trivial, or uninteresting, thing to do.

John Larkin Highland Technology, Inc lunatic fringe electronics

On a sunny day (Tue, 24 Oct 2017 11:31:34 -0400) it happened bitrex wrote in :

So you are hiding your crimes againts humanity, does that make it right?

On a sunny day (Tue, 24 Oct 2017 11:14:09 -0400) it happened bitrex wrote in :

Dont't worry, good chance trump will make sure you do not have to work that long ;-)

No idea what that is.

We had a discussion here recently about starting an other business. Cannot tell you what it is, but it is on the web somewhere so may pop up sooner or later so to speak.

reading from flash should be possible in parallel with the registers being pushed on the stack, so there should 12 cycles to fetch a vector and then the first interrupt instruction

Write the dac first, clear the interrupt flag and then compute and save the next dac value.

This email has not been checked by half-arsed antivirus software

The day the Hague sends me a letter of protest about it is the day I'll start to worry

Pfft, as if America was so kind to me and I love this place so much I want to spend the rest of my "youth" sitting around fighting over it. What're the Netherlands or wherever like this time of year?

List of primary America negative points having lived other places: s*it's expensive, full of unfriendly chronically pissed-off people walking around with a scowl on their face all the time, nightlife is expensive, drinks are expensive and usually watered down, fake annoying people who talk about the stupidest s*it, have to pay out the ass for healthcare unlike every other Western nation in the world, American women curse all the time like dudes, people obsessed with sports constantly, gigantic police budgets so you have the police breathing down your neck every five seconds, outside the Northeast and California everyone is obese.

I just watched someone in an $80,000 BMW drive over a curb in a McDonald's parking lot and smack into a loose shopping cart; pretty much sums it up.

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