Hi everybody.
I wanted to give you a quick update on the Gigatron.
This is the computer that has no microprocessor.
I did a video about this around 6 months ago, where I assembled the kit and demonstrated
what it could do.
And one of the things I complained about is that there was no keyboard and no way to really
do anything on it outside of the few programs it came with.
Well, that may change now.
I’ve been sent a new ROM chip which promises some much needed new features.
And here is something called Pluggy McPlugface and should allow me to connect a keyboard.
So the first thing I’ll do is take a look at this keyboard interface.
As expected, I’ll need to assemble it myself.
There’s just a few components, but I noticed this note about mounting U1 to the other side
first.
I guess I’d better do that or it might be difficult to assemble the rest.
So, this is U1, it’s a tiny little micro controller with only 8 pins and a socket.
It’s amazing how small it is.
I didn’t even know you could get micro controllers with so few pins.
So, anyway, I’ll go ahead and solder this thing into place.
And next I’ll go ahead and stick the DSUB connector on there.
And then I’ll turn that around and solder that into place.
And then I mounted the PS/2 keyboard connector, and believe it or not, that is all there is
to this particular device.
This actually plugs straight into the joystick or gamepad port on the rear.
Of course, in order to make use of this, I’ll need to remove this version 1 ROM chip.
And then I’ll put version 3 down in here.
I never saw version 2, so I guess we’ll skip right over that.
Now I’ll plug in my PS/2 keyboard.
And let’s power it on.
I notice there are a few more things on the screen now.
The good news is I can use the arrow keys on the keyboard to navigate.
Let’s try Tetronis.
That sounds like a Tetris clone, and I hope it is!
And it is!
I wasn’t expecting it to have a musical track as well.
There’s something really dirty about the waveforms produced by the Gigatron.
I know they are all software generated, but they don’t sound like square waves, but
not quite like sawtooth either.
I’m not sure what the reason for that is, but still it works.
And considering the technical constraints of this computer, it’s hard to complain
about much of anything.
And this Tetris game is very playable.
I don’t know what I pressed, but I somehow triggered an Easter egg.
However, this would be a good opportunity to show the new speed modes.
So, as you know the Gigatron uses software to generate the video display.
So these blank scan lines you see is when the software switches to allow the CPU to
do other stuff.
The new version has 4 different modes you can access with page up and page down.
This is the slow mode, but all scan lines are used.
And then you can speed it up like this.
Each new speed sacrifices an additional scan line.
OK, let’s try bricks next.
OK, it’s like a break-out clone.
And it’s not half-bad, to be honest.
I’m sure Steve Wozniak would approve.
And next I’ll try the Tic-Tac-Toe game.
OK, this looks like it was written in BASIC and seems really similar to the version that
is inside this old BASIC book from the 1970s.
It’s clearly not optimized for the Gigatron since it treats the screen like a plain text
terminal.
Well, speaking of BASIC, let’s take a look.
So, it runs TinyBasic version 2, and you get a little over 9K to work with, which isn’t
bad.
That’s 3 times what the VIC-20 had.
The screen, of course, is very low resolution.
And this has to do with the way the Gigatron generates its video signal.
So this means we get a text resolution of about 26 by 15 characters.
That’s actually less text that the Commodore VIC-20 could display.
So it takes some getting used to with such chunky characters.
BASIC works more or less like expected.
I thought I’d try typing in one of their example programs on the website that turns
the keyboard into a piano.
I printed it out to paper to make it a little easier to type in.
This reminds me quite a bit of typing in programs from books and magazines back in the 1980s.
OK, so here’s the program in its entirety.
Let’s run it.
OK, that was to be expected.
Finding a syntax error is part of the experience of manually typing in programs.
Another odd thing I noticed is that the LIST command doesn’t work like on other computers.
I wanted to just list LINE 2 but it doesn’t seem to recognize that.
So to look at something I have to press control-C at just the right time to stop the listing.
Anyway, I finally found and fixed all of the errors.
So these are the keys on the keyboard that I can use for playing music.
Let’s see if I can play something else.
Rats, not enough keys.
OK, so here’s something I think you’ll find interesting.
If I type SAVE, it will save this program.
No filename or anything.
It’s kind of slow and saves one line at a time.
But the Gigatron doesn’t have any non-volitile memory.
So where is it saving it to?
Well, believe it or not, it is saving directly to the little micro controller on the keyboard
interface.
However, it doesn’t have much storage, only about 500 bytes.
So, that works out to maybe 20 to 30 lines of BASIC code.
This piano program is about as big as can fit.
However, if you use one of the larger controllers that are available, it has a larger storage
space.
OK, so once it’s saved, how do you get it back after power cycling the computer.
Well, you might think you type load.
But that doesn’t work.
So apparently, you press Control and F3 together and it starts this up.
What I think is happening here is the keyboard controller is simply typing this code right
back into the BASIC interpreter for you, rather than loading it into RAM.
Still, it works.
Here’s something else cool.
You can use POKE and PEEK.
Memory address 43 contains the foreground color.
And zero is black.
I think that may be somewhat easier to read.
Oops.
Typo.
You can also change the background color with address 42.
I think white on black is much easier to read than the default color.
But speaking of colors, I wanted to write a little program here to take a look at some
of the colors.
While the Gigatron has very limited screen resolution it does make up for it somewhat
by having 64 colors, and all of these can be displayed simultaneously with no limitations.
So in that regard it is better than most 80s computers.
Here’s another little program I wrote to play around with colors.
And while I was thinking about it.
If you remember the episode I did on the Maximite computer a while back I wanted to see how
fast it could draw random lines on the screen.
Turns out it was pretty darned fast.
And I had compared it to a similar program on the Commodore 128 which ran at about this
speed.
So I was curious how the Gigatron would stack up.
It took me a bit to figure out how the line commands work, because it isn’t like I was
expecting, but I managed to get it working.
And the speed is in the same ballpark as the Commodore.
But, keep in mind we have 4 different speed modes here on the Gigatron.
So if we put it in the slowest mode that uses all of the scan lines, then it is painfully
slow.
And so let’s try going to the next mode.
OK, that’s quite a bit faster.
And the next.
OK, even faster, And here’s the fastest mode.
So, what other neat things can you do?
Well, the screen-RAM location can be moved.
And if you type this command, you’ll actually be able to see what’s in other parts of
RAM.
In fact, you’ll notice as I type, you can see changes over here, which I think is the
command buffer.
Also, remember the blinkenlights?
You can modify those too with address 47.
Apparently a 9 is the default delay time, but if you put something like a 2 in there,
you’ll see the lights speed up a lot.
And if you change it to a bigger number like 20, you’ll see it slows down.
Using address 46, you can stop the animation completely and control the LEDs manually.
So, if I wanted to turn them all on for example, I could put in a 15, which in binary is four
ones.
Or a zero to turn them all off.
Or if I just wanted two of them on, I could put in a 3.
Again, you have to think binary to know which lights this will affect.
Of course, you could incorporate that into a BASIC program and create your own custom
blinking patterns.
So, what is the final verdict on the new Gigaton update?
Well, don’t throw away your X-box or your gaming PC just yet, but I think it’s a really
fantastic update compared to the one I reviewed 6 months ago.
I mean, now it’s interactive and there’s a lot of neat things you could do.
And I could probably spend a lot of time writing little neat programs for this.
For example, one program I thought would be really cool would be to create an art program
in BASIC.
And I think it would be perfectly capable of running such a program.
You could create pixel art and stuff like that.
I think it would be really well suited to that.
The only reason I didn’t do it is because there’s no real way to save the program
just yet because my micro controller that it goes into wouldn’t hold a program that
big.
But, it could be done.
And that would be something that would be fun to do with it.
Anyway, so that about wraps it up for the Gigatron, but I had a couple of other things
I wanted to mention.
In fact, quite a coincidence.
The last time I did a Gigatron video, I mentioned something at the end of the video about what
my dream computer would be.
And I posted an article on my website and a link to it.
And a lot of people went and looked at that and discussed it and I got a lot of feedback
on it.
Well, I’ve actually updated a new article which I’m putting a link to in this description.
Because things are moving in this regard!
So, I’d be curious to see what you think of the new ideas and the progress being made
in that front.
So, check that out.
And, speaking of updates.
A while back I did a review on the C64 mini.
A little modern version of the Commodore 64.
Well, I just actually received a new version of this which is the release for North America
and it’s got a lot of new updates and supposedly fixes and improvements on it.
So, I’m going to be doing an update on that here next and well see.
I’ll run it through it’s paces and we’ll see how much it’s better or if it is any
better.
So anyway, stick around for that, and thanks for watching!