ganz kleines bad einrichten
welcome to another episode of the 8-bit guy! in this episode i'm going to be showing you the koalapad! now this is a really interesting peripheral from 1983, and it's primarily used for designing artwork, but really, it's just a pointing device. and i'm going to show you how it works. it was made for the commodore 64, the apple ii, the ibm pc, and the atari 8-bit line of computers. so this particular version is designed for the commodore 64, so i thought in this episode i would use the commodore 64c. it rarely gets much screen time.
i'm usually showing the old bread box commodore 64, but this works just as well. in fact, i kinda like it better in some ways. when you open the box you see that it comes with the pad, some books, and a cartridge for the koala painter software. this software was also available on floppy disk and cassette. i actually like the cartridge version because it loads immediately, but you'll still need a storage device if you want to save any of your work.
ok, so it's supposed to come with a stylus but mine didn't have it. now, it's just a touch-sensitive surface, so i'm just going to use the blunt end of a ballpoint pen, and i think that'll work just fine. so when you put in the cartridge and then you power on the computer you will see this neat little intro screen. it may not seem that impressive, but notice at the bottom that it was made in 1983, so, this was actually pretty cool since the commodore 64 was still in its infancy at this time, and most of the software that really exploit its graphics capabilities didn't come out until several years later.
now you'll notice it starts drawing a little scene here. this is actually pretty neat. it's actually using its own polygon drawing routines in order to create a little scene based on some simple coordinates. these routines definitely aren't the fastest fill routines ever compared to some of the c64 demos you see these days, but i tend to cut a lot of slack again because we're talking 1983. so when you press one of the buttons on the pad, it will move to this menu, and you use the pad sort of like a mouse. might i remind you, by the way, that the only computer for consumers that existed at that time that used a mouse pointer like this was the apple lisa, which costs as much as a brand new car.
so i'm going to draw something here. just a little something. now what's interesting here is that they have a button called "oops", which i think is the first-ever instance of an "undo" button i've ever seen. so, let's try this again. ok, so i created some abstract masterpiece here. now let's see if i can fill it with some colors. ok, i'll pick blue... drop that in this place. ok, so now let's pick yellow and try that.
i suppose i should point out that this is using the commodore's multicolor mode, which i talked about in a previous episode. this allows up to four colors to be used inside of an eight-by-eight color cell. so as long as you don't try to put too many colors right next to each other, you can avoid the clashing. now what's interesting is that they have the main 16 colors appear in this section, but down below they have like some dithered colors with alternating
pixels to kind of give fake extra colors. forgive my video capture device, it seems to have gone nuts with some interference here. anyway so here i can fill in one of these fake colors and has kind of a textured look to it. so enough of my artwork. let's go over and hit up the storage and let me see if i can show you some example artwork. so i have a disk in the
floppy drive. it has 11 images on it. i just found this disk so i'm not sure where these came from. anyway i'm going to click "get", and then move the pointer up to "invasion". now this takes about 30 seconds to load from disk. ok, so let's go back to the main menu and then back to the drawing screen i'm not entirely sure what the idea was behind the little boxes, but these
are some pretty good multicolor art pieces. let's go use the "zoom" function so we can get a close-up of some of the areas. this is how all of the pixel art was really drawn pixel-by-pixel. you really have to give these artists a lot of respect for being able to create stuff like this. so naturally, i'm very curious as to how this thing works, so i have a hunch that it uses the same pins on the joystick port that would be used by paddles.
the c64 has two pot inputs on each port for a total of four. pot stands for "potentiometer". this was originally intended for use with paddles like these, so i wanted to do a little test, and so i plugged in my paddles. so if you want to read the register for the first pot input, you can use the peek command for memory location 54298. but to make this easier, i'm going to write a little basic program that will show me both of the pot registers on port 1. ok, so now i'm going to add a little "go to" command so that it will just keep repeating this command over and over again.
now, you can see there's some fluctuation in the numbers, but they're holding fairly steady. now you can watch as i rotate this paddle. you can see the numbers changing. so now let's plug in the koalapad and keep running the same program. sure enough you can see the koalapad is definitely sending information on these pot registers just like a paddle. so it uses one register for the horizontal position and one for the vertical. one interesting little side note about the pot registers. so if you look at the motherboard of the c64 the chips that read the joystick lines are the 6526cia chips, the same ones
that handle the keyboard, and most of the input and output lines for the user port, disk drive, etc. but the pot lines are actually handled by the sid chip. that's right. the chip that gives the commodore 64 its unique musical sound is the same chip that makes the koalapad possible. ok, so i guess we better take this thing apart so we can see what's inside. uh-oh. it looks like we run into one of those screws hidden under the warranty sticker.
i guess i'm gonna have to void the warranty. ok, so let's take the top off, and then the two buttons. now we can remove the pad. it's pretty simple looking. but there's a circuit board in here. i'll be honest, i have no idea what these different integrated circuits are for. here are the little momentary switches for the buttons. and i do see a date code here that this one was manufactured in february of 1984. also the koala pad will work in geos as a pointing device.
that's a graphical operating system that came out for the commodore 64 in 1986 about three years after the koalapad came out. so there were a handful of other third-party applications that also supported the koalapad. this is a really neat piece of computer history because a lot of the early games, they use these to design the graphics that you see in those games. and you know i also love the innovation. not only of the tablet but of the software itself, because again we're
talking about a pointer driven operating system. or another operating system, right where they released a pointer point-and-click driven application in 1983, and most computers didn't start seeing that type of thing 'till many years afterwards. i've also collected a variety of other interesting peripherals from the time period, and i'll be showing you those in upcoming episodes so stick around for those, and thanks for watching. {edited by busysteam5}