Thursday, July 30, 2009

Rebuilding Apollo...

or at least the AGC.

OK, I've been busy. Between work and home I occasionally want to run away screaming.

But, to follow up on my previous entry, here's someone who built a AGC. With helpful details and plans to let you follow in their footsteps...

Monday, July 20, 2009

Retro computer hardware...

Before the PC revolution, computers took a lot of dedication.

You spent lots of money (or time, if you didn't have money) to buy / rent / build a computer.

Sometimes it took both money and time. Like building a computer completely out of NAND gates.

But the results could be very impressive. After all, one of these ancient machines took us to the moon 40 years ago today...

Friday, July 17, 2009

In the Beginning...

it wasn't the command line.

The actual beginning was hardwired logic circuits.

Then came machine code.

Then came Assembly language. That's far enough back for me...

So, you want to program your little toy? I've seen lots of programms think that Java or C++ or <insert language of the week here> MUST be the way to do it.

But all of these systems assume lots of system overhead is available. That isn't true for small systems. That's why languages like C and Assembly are the standard in microprocessors.

"But I can do more with <FOO>!" Nope... when all is said and done, everything compiles down the instruction set of the target processor. That's all it can ever be.

While some languages make it easier to do particular things, they cannot make the processor do things that another language cannot.

This brings us to Assembly. Anything that can be done in any language can be done in assembly. No compiler, however smart, can make things more efficient than a good assembly language programmer.

And, if you understand assembly for the target processor, you know what the hardware is and is not capable of. Which means that, even if you use a high level language (and whether or not C counts is a matter of debate), you can write better code because you know how your code is going to map onto the target processor.

So, go to someplace like Webster and find out what a compter is actually capable of.

Tuesday, July 14, 2009

ET Phone home...

or at least Mike S.

He actually ran across my datapackrat website while doing a search on Wendin. And that led him to this blog.

He emailed me (at the datapackrat address), but never replied to my response.

Mike, if you're still out there, feel free to email me about old software.

Wednesday, July 8, 2009

Get them while they're hot...

Since Geocities is going away, I'm going to post all my Geocities links so you can browse them (and maybe archive them) before they are gone.

R. J. Kunh has a site for robot enthusiasts, with microcontroller hardware and software links.

Ted Rossin has an electronics page for PIC microcontrollers, Z8 microcontrollers, and more.

GKDesign has a homepage, with plans for a solid state oscilloscope.

I did have some more, but checking them out I find that they also have independent pages (or, at least, independent DNS). Ricci Bitti does electronics, including a video DVM. Jason Shayer has moved his 80's Marvel Comics page to a blog.

Monday, July 6, 2009

The joy of spending...

Time is money. So is money...

It may sound weird, but with the bad economy interest rates took a steep plunge.

Since my wife and I needed some work on the house (heating and air conditioning, the AC died completely last fall), we decided to refinance at a low rate and take money out to do stuff.

This works because you basically reset the 30 years (or whatever period you had) of your mortage back to 0. With a lower interest rate and a lower principle, you get a lower monthly payment. If you do it right...

So, HVAC has been installed. And since (my wife claims) we aren't going to do this again anytime soon (I want to say 20 years...), we're doing a lot of projects around the house. Some electrical work. New driveway. Refinish floors. New furniture. Plumbing improvements. More.

This is a lot of stuff. And some of it (like floors and furniture) means that we have to have EVERYTHING out of the room(s). So, we're about half moving out of the house to do this. Much fun.

And I don't even want to start thinking about what we have to do with the cats when they need to start working on the floors...