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Anybody Into Programming PICs?

I'm beginning to wish I hadn't started this. I could have had a logic circuit up and running by now - and hardware is inherently multi-tasking!
 
Strictly, of course, black holes do not suck. You fall into a black hole.
 
I suppose you are right, but that led me to thinking what does 'suck' actually mean?
I guess it's to do with lower pressure rather than higher gravity.
And as there isn't any pressure differential in deep space...
 
But as you know, physics isn't necessarily real - it's just that the equations produce useful predictions.
 
Real: not a figment of an active imagination

What I am expressing is fact usually overlooked by physicists: (for example) just because the properties of light are usefully modelled by calculating the consequences of a wave-particle duality does not mean that light is a wave-particle duality (etc).

If it looks like a duck and quacks like a duck, it is only a duck as long as you have no experience of anything else able to look and sound like a duck under those circumstances.
 
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Oh, I agree. And cause and effect too. One situation doesn't cause some later situation. It's just that there are equations that predict the second situation after the first, and equations that are reliably predictive.

Curved space-time, though, is too simple and delightful to exclude from reality, unless you are a Platonist.
 
I think this is something not sufficiently drummed into students: replace "is" with "behaves as if".

Curved space-time? Again, a useful way to think about, but not necessarily the way the Universe really is. To be frank, the notion that physics is just a method for mathematical modelling that happens to yield useful results is the only way my mind does not explode at the concept of 26 dimensions (or whatever the current front-runner is).
 
Infinite numbers of dimensions in classical QM. (An infinite dimensional Hilbert space with observations being operators on it.) Plus, phase-space is hardly "real."

I have no problems with dimensions (is a hair 1, 2 or 3 dimensional?) but the unforeseen consequences of space-time and curved space-time are too compelling to dismiss as unreal. Few would argue that "ordinary" space is not three dimensional. It is part of "reality." On the other hand, saying that the universe is 2D because you can solve boundary value problems using 2D boundaries (or the equivalent holographic version) is just muddled thinking IMHO.

Tricky distinctions!
 
Seduced by the dark side: "if it looks like a duck and quacks like a duck it is a duck"!

Mike0001 said:
An infinite dimensional Hilbert space with observations being operators on it.
Click to expand...
An artificial mathematical construct if ever I heard one.

This is getting dangerously close to theology.
 
Black Hole said:
Seduced by the dark side: "if it looks like a duck and quacks like a duck it is a duck"!


An artificial mathematical construct if ever I heard one.

This is getting dangerously close to theology.
Click to expand...

Not at all. The waves vibrating on a finite string form an infinite dimensional Hilbert space. One basis of it is what we call the fundamental and harmonics. The inner product ("dot product") is just the integral of the product of two functions along the string. It's elementary Uni mathematics.:whistling:
 
I bought a cheap Arduino Uno clone on ebay for about half the price Maplins sell them. The IDE is very nice and all 'C'.
 
Black Hole said:
just because the properties of light are usefully modelled by calculating the consequences of a wave-particle duality does not mean that light is a wave-particle duality
Click to expand...

Define is!

If it looks like a duck and quacks like a duck, to hundreds of decimal places, only a madman would claim it isn't a duck. If I fire a gun at you, at close range, are you going to say "Yes, but it only appears to be a gun, and I can't be absolutely certain?" If you see what appears to be another human, are you going to claim that it only behaves like a human but isn't really a human? There is no point in that philosophy, it is and always was a dead end as far as useful predictions are concerned, and is certainly not part of the scientific method. Nor is it a sane philosophy: such doubt in any other sphere would have you locked up, with the keys thrown away!

So, curved space-time is, to a very high degree of accuracy, how space-time behaves. You can say it isn't really curved, but you can't deny that it behaves just as though it is curved, or that space and time are traded off against one another. You cannot deny that space and time are not mutually exclusive. Nor that light bends round massive objects. The latter is an observable consequencesof the curvature of space-time. If you think there is something out there which is, but is not curved space-time, I defy you to explain what is actually means?

It's like saying "You can't know if there is or isn't a god." Fair enough, but only if you can define what a god is, as something that lives outside of existence and never interacts with existence, because if it did it would be susceptible to scientific investigation and would be a natural phenomenon. If you don't make clear what your terms are, you can't play the agnostic existence card! Define what existence of a god would be. Similarly, define what space-time is if it looks and feels curved but isn't!
 
You did warn us that God might brought into the conversation BH. I thought that light bending around a massive body was due to gravity. But WTF do I know?
 
Doesn't somebody getting hot under the collar because somebody else doesn't happen to share their views remind you of something else? Philosophically I can't tell the difference between a mathematical construct which fits the observed facts and a theological construct which fits the observed facts - although of course the mathematical construct produces useful predictions whereas a theological construct produces nothing useful at all (except jobs for the boys).

How did this get so far from PICs?

I'm suffering from a lack of dedicated time to sit down and crack it. I have fiddled with the PICAXE IDE, so far putting my pseudo-code into the "compiler" as comments and converting the first few lines to the BASICish code, but the language reference document is too long to print out and yet is lacking in what, as a hardware engineer, I would call adequate detail. AF's code in a previous post seems to lack IO initialisation, but seems to get away with it. Why? I can't find anything in the documentation to explain. My use of the pin descriptors doesn't seem to work in the simulator, but I'll get there.
 
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Black Hole said:
AF's code in a previous post seems to lack IO initialisation, but seems to get away with it. Why? I can't find anything in the documentation to explain.
Click to expand...

Does this excerpt from the manual explain it? The chip I have is an old one and it looks like many things, including pin naming conventions, have changed.

Code: 
Selecting Inputs or Outputs.
When the PICAXE-08 first powers up, all pins are configured as input pins (except
pin0, which is always an output). There are three methods of setting the other
pins to be outputs (if required)

Method 1 – use a command that requires the pin to be an output.
This is the simplest method, used by most educational users. As soon as a
command that involves an output pin (such as high, low, toggle, serout or sound)
is used, the PICAXE-08 microcontroller automatically converts the pin to an
output (and leaves the pin as an output)
 
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