Some old Hi-Res pictures from the Apple II+ from back in the day

[Keatah]

A lot of stuff relied on this behavior, but even more so, a lot of stuff took care to work around it for different visual effects.

 

Part of the fringing thing, it's a nostalgia factor. And in a radio talk show, C2C AM with Art Bell and George Noory, Woz said he often did things with parts that were not intended to do what he did. He made this kind of circuit that spun around and stuff, and the bits chased each other like a dogtail. And this ran at 3.58MHz and interacted with the chroma color things and made stuff blank out and these little blips that spiked the color killer circuit. And the off-kilter static based on timing spikes in relation to dot position is what made the different colors in the Apple II..because Apple 2 pixels have no color intelligence. All this was done with 1 or 2 TTL chips and 558 timer thing. Cool, eh?

 

The Apple-published reference manuals are good on this topic. The 2 books by Jim Sather are even better.

http://mirrors.apple...0Project/Books/

 

It is amusing what a prankster Woz is. He loved walkie talkies and built a modified one that would interfere at the Mc'Donalds drive through. And when somebody would place an order, he'd come on the horn and overpower the radio and say, "Sorry, we can't accept this order, you're too fat."

Edited March 3, 2012 by Keatah

[potatohead]

I am reading through Jim Sather right now actually. Great book, covering the machine in very good detail. I like this about the Apple computers, built just early enough to be completely open in this way. We are getting the guts of POKEY, ANTIC, SID, TED, VIC, et al. now, but it's been a long while.

[potatohead]

BTW, that emulator version linked here is really good. Very nice artifacting emulation.

 

I split off a few of the pictures to a standard floppy, so I could view them on the real deal and capture. Open volume in Ciderpress, copy off necessary files and a few pictures, the basic goodies, and that picture list. Extract picture list to PC, edit it to reflect the ones on the disk, copy back to the disk image, done!

 

http://www.atariage.com/forums/blog/105/entry-8920-image-container/

 

Thanks for the library of pictures Keatah. Appreciated.

[Keatah]

I am reading through Jim Sather right now actually. Great book, covering the machine in very good detail. I like this about the Apple computers, built just early enough to be completely open in this way. We are getting the guts of POKEY, ANTIC, SID, TED, VIC, et al. now, but it's been a long while.

 

I'm not sure which of the aspects of the 2 series I like best. By that I mean, the sound generation, or video, or keyboard interface, or memory decoding, that sort of thing. I personally believe the Disk ][ controller card - the interface card with 6 chips, that plugs into the slots - is some of Woz' best work. The simplicity and elegance of the state machine on the card is brilliant. You have basically a very simplified uP made from a 256 byte ROM and an LS174. Astounding! And it worked!

 

Perhaps I'm biased because the Disk ][ was perhaps the most coveted of peripherals BITD. I had to save money all summer long, and often times I'd go to the grocery store to "take the bottles back". I'd cruise the neighborhood with my RadioFlyer and collect all sorts of soda bottles and turn them in for cash. Couple of dollars was almost guaranteed on trash day. That and a paper route, and other odds and ends and soon enough this spoiled brat of a 4th grader got his own floppy disk drive! And quickly thereafter I ran into some big money and could afford a 2nd drive for high-speed copying.

 

Or perhaps it was because I wanted an interface to control motors and relays, and I used the interface card to move my home-built radio telescope around. It was one of my first computer-controlled electronics projects. I had it rigged up to not only turn the dish (pounded into shape from a pilfered trash can lid), but to also operate a geared motor which would turn the dial on my radio receiver with great precision. The paddle ports would then sense the signal strength through a little custom circuit and then tune the radio for maximum strength. Then same thing with the dish, back and forth, locking onto the signal good and solid.

 

I didn't fully understand machine language, but I knew Applesoft basic real good, and I'd just poke RWTS to get the stepper motors going. Cool!

 

This was serious engineering going on here! ahaha!

Edited March 5, 2012 by Keatah

[Asaki]

It is too consistent to be anything but a screencapture from an emulator. I just got the NTSC Applewin emu, I can't believe I missed it.

 

I figured it was an emu, but I tried a few of them (including AppleWin) and couldn't get any of them to look that good.

[Osgeld]

And then I found this, which I'm not even gonna try, somebody made a script or something that converts an Apple HGR screen into a series of HPLOT x,y basic statements! Good god!

http://www.macshock....hgr-modes-2548/

I was looking for something totally unrelated and came across this thread...

 

Anywho I wrote the script on the broken link above, here is a working link to the original news post

https://groups.google.com/forum/?fromgroups#!searchin/comp.sys.apple2/ghetto/comp.sys.apple2/tEL5ulY-dPY/esNpF_G-xpkJ

 

I intended to do an apple II game for ludumdare, but never finished, but right before start I decided I needed a way to quickly paint and render apple II HGR screens on my PC. What you do is use the gimp with a special 6 color palette in a 280x192 screen and save it as a portable pixel map file encoded with ASCII.

 

The lua script runs though the file picking out the specific colors and makes a metric ton of HPLOTS and HCOLOR statements. Take that output file, copy and paste into Applewin with the CPU speed option cranked to full speed, and it will redraw the graphic in the apple memory in ~10 seconds, bsave to disk and transfer to a real machine and your off and running.

 

Its a totally brute force ghetto way of doing it, but it served its reason. It does not account for odd bit patterns or color fringing so its not directly WYSIWYG but its predictable if you have messed with HGR enough.

 

 

EDIT: I also did the Apple II weather display which does a very similar thing using imagemagick and a lua script on the fly (though painfully slow to send over the serial port at the time, need to rewrite it with a serial port driver, going from 300 baud to 115,200)

 

Edited September 17, 2013 by Osgeld