#243

Playing With Computers

Thursday, October 29th 2020, 6:04:43 pm

Invent everything,
we are all extremely smart.
We can learn anything,
so as long as we don't skip any steps along the way.
And so as long,
as all steps are interesting and fun to us.
Never force yourself to learn something you don't enjoy,
just keep reading books, and keep looking for something to strike your fancy.
From Dreaming, and Inventing,
to Art, Programming and taking to the skies.
 
An invention can be as simple,
as an LED Throwie or LED Glowie.
Just a Light Emitting Diode, a battery and magnet,
to keep it all together; and as a bonus make it stick to metal surfaces.
That is a three component invention,
LED, magnet, battery.
 
My favorite Radio Astronomer,
Quips, that the baseline for determining if a member of a species is intelligent,
is whether or not it can hold a soldering iron, and make a radio.
Allow me to get you soldering a radio,
as quickly as possible.
 
Get a Raspberry PI Zero W (the W stands for Wireless or "with WI-FI"),
a soldering kit, a solder wick, some GPIO headers,
and a 4 x 8 RGB LED HAT that fits a Raspberry PI Zero neatly.
Look everything up on YouTube,
how to solder, how to solder headers, how to use a solder wick.
 
This is serious business,
in last few years embedded Linux became extremely inexpensive.
that includes a case, power adapter, heat sinks, and a header.
At first you connect it to a keyboard and a monitor,
and set it up on the network.
But later as you figure everything out,
you unplug everything leaving just the power.
To get inside it,
you use a remote terminal.
Once you login,
you get a command prompt.
It listens to words, to commands,
very similar to adventure games.
Indeed, directories on your hard-drive,
are very much like rooms in a game.
To get inside Documents,
type in "cd Documents"
The command "cd" is short for,
Change Directory, a Directory is the same as a folder on windows.
When you say "cd Documents",
you are giving the cd command an argument, or an option, or a setting, or a preference.
The cd command is a perfect example of how command line interfaces should work,
just a couple of words and nothing more.
But sometimes, that is not enough,
like for example when you want to ask "cd" for help.
We can't say "cd help" becasue then the cd command would search for a directory named help,
we have to make the second word special, to do that you use hyphens.
You can type in "cd --help",
it will notice the hyphens, and print out some helpful information.
To see what is in a directory, type in "ls",
which is short for list, or list files.
"ls" also accepts special inputs,
you can ask it for help like above.
But also ask it to list files in a long format,
by saying "ls -l" here we use a singe hyphen, because "-l" is commonly used,
the -l is short for "--long-listing", but nobody bothers spelling that out.
To list files with readable file sizes,
you have to add -h, here -h has long form, and some people may use spell it out as "--human-readable"
Usually when writing complex commands that other people will use,
the long form is preferred, bu when you are just typing on the command line and want to do something quickly,
you just use the short versions.
The command line interface is trying to be your friend,
it wants to function with just one or two words, but it also some with extras like the --human-readable flag.
There are many tutorials on how to use the command line,
and many books, my favorite are the pocket books, take a look at O'Reilly Bash Pocket Reference
Here are instructions on how to play audio through HDMI,
your monitor should have an audio out somewhere.
 
Now see if you can get that GPIO header soldered on,
and try to blink some of the RGB LED HAT lights based on this tutorial.
Alternatively you can just blink a simple LED based on this instructable,
note that a standard Raspberry PI 4 8GB comes with the header soldered on to make things easier.
And there is also a Raspberry PI WH,
meaning Wireless with Headers pre-soldered.
 
And now, get a $10 camera,
and use raspistill to take a photo,
and play around with all the other options.
 
Now you have an inexpensive platform for your inventions,
a programmable machine, that you access over the radio of your wireless network.
You can make it blink, or take time-lapse photographs of the next snow storm,
you can get an LCD screen and turn it into a tablet.
Raspberry PI is not the only Single-board computer,
PINE looks really nice as well.
If you are looking for a more complicated project,
perhaps try building a Raspberry PI Drone,
bonus if you can get it to cross the Atlantic.
 
We have no limits,
but we are also very unique.
Our inventions need not rely on commuters,
some of the greatest inventions the Human Kind has seen, were just ideas.
Don't let anybody stop you from inventing,
and don't stop dreaming.
Finally, the most impractical and outrageous inventions,
make for the most magnificent Videos, White Papers, CVs, and Resumes.
Aim,
for the Moon.

#243: Playing With Computers

Thursday, October 29th 2020, 6:04:43 pm

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