Chilly Willy

I used a 720K drive using the guts of a normal 3.5" external drive. The computer thought it was a 3.5", but the only difference with a 720K 5.25" drive is the size in any case. Most external drives are designed so that they shift the select lines over one, use the new "drive zero" for the drive it's controlling while passing the rest through to the daisy chain. Makes it really simple.

It's amazing how fast this is. You've really got some efficient code going there.

Uhg... must be getting old or something. The way it works is like this: It goes through the bsp tree looking for sectors on the same side of the player as the way he's looking. If a subsector is found, the segments are all checked. Each line segment has its start and end view angles computed, which are clipped to the angles corresponding to the screen. The line segment and clipped start and end x coords are stored for later. So it really isn't a raycaster in the traditional sense. Sorry about the confusion... most of which was my own.

Yes, this is true. I should have been more specific. We were talking about the newer x86 where Motorola finally gave up trying to keep up, and I was pointing out that Motorola switched the 680x0 family into the RISC based ColdFire family, which allowed them to up the speed while maintaining backwards compatibility with a library for unsupported opcodes, and how Intel basically did the same thing - converting the x86 from a full CISC processor into one with a RISC core for better speed, and a translation layer to keep the same ISA. Came out in Oct 87. I got one in Jan or Feb 88 to replace my Atari 400. You know, I came THIS CLOSE to working for GVP in 1990. I was in talks with them to fly out for an interview, then the war in Kuwait/Iraq started and I never heard back from them.

You must not be an engineer, nor read ANY boards that talk about hardware. I suggest you google "x86 risc core" and prepare to be blown away.

The CLICK is an unused GPIO, nothing to do with audio. And there's NO MIXING in the GTIA. All audio is handled external to the GTIA entirely - the SIO audio is mixed by an external circuit with the POKEY audio, while the GPIO line from the GTIA goes to a transistor to the speaker on the old consoles, and into the external mixer on the newer consoles.

Yes, there were instructions on how to do it yourself in magazines and on BBSes not long after the A3000 came out, but you really needed to be sure you weren't all thumbs as more than one person managed to kill both their A3000 and Toaster doing it themselves. If all you would up with for trouble was not as nice a looking job, yuh dun good!

At one point in time, I had my A500 with the Fatter Agnus, 1MB of chip, 2.75 MB of bogo mem, a 25MHz 68030 with 8MB of ram, a Slingshot adapter plugged into the side (which gives you two standard A2000 style Zorro II slots), with a Ethernet card in one slot, and an EMPLANT card in the second slot. I did all my EMPLANT development on that for at least a couple years before finally getting an A4000 to do EMPLANT development on.

The GTIA has no real sound resources on it at all. An unused GPIO (general purpose in/out) line was used to toggle a speaker on the old 400/800, and that was the extent of "sound" in the GTIA. The sound chip on the A8 is the POKEY, which also handled serial and keyboard interfaces. This became the PAULA chip in the Amiga. Perhaps the simplest upgrade Atari could have done to the A8 line would have been to double the speed of the ANTIC/GTIA path. 160 wide color modes would have become 320 wide color modes, and the 320 wide B&W would have become a 640 wide B&W. The GTIA modes would have gone from 80 wide to 160 wide. It would have required memory to be twice as fast, but memory got cheaper and faster all the time. Make the speed switchable for backwards compatibility and you would have had a really nice upgrade.

A box with several slots and make a retro version of SLI with ANTIC cards.

Actually, you could MAKE it fit, but doing so would void your warranty. I knew quite a few folks who took their Toaster and A3000 to certain shops that would do the fitting for you and warrant it themselves... for a price.

In the fall semester of 87 at college, I used my Atari 400 to do a solution to a bounded planar electric field from a 2D source, requiring Eigenfunction expansion of a 2D partial differential equation. It took almost four hours to compute. I decided right there it was time to move on, so I did my research and bought an Amiga 500 in early 88. I knew I wanted a 68000 based system (all the best systems were... the ST, the Amiga, the Mac...) and while the CPU in the ST was slightly faster, the Amiga beat it hands down in every other respect. And we had a few Amiga 1000s in the lab, so it was easier to take stuff back and forth going with the Amiga. When we needed something more, we had several NEXT boxes for the high end stuff.

Yeah, if you can have the function deal with the BMP directly, that's much easier on the user - they just include some BMPs with their project. They just need to make sure they're in the proper format.

I am an engineer, both of hardware and software, so when it came time to update from my venerable A400, I looked into it, and it was OBVIOUS even 25 years ago that the Amiga was the successor of the A8. It wasn't heretical, all us engineers knew and acknowledged it. So even if it meant changing which company we bought from, we bought the design we knew was best and most familiar to us. What was also clear was that the ST was NOT the next generation A8.

Actually, Doom IS a raycaster. What is different is the method used to determine the intercept points with walls. Wolf3D uses a regular grid to represent walls, while Doom uses a BSP tree. Each ray is cast like a normal raycaster, then for each sector the ray enters, line intersection calculations are done between the ray and each line segment inside the sector. If there is no intersection, or if the line segment indicates the wall isn't solid, the ray is advanced to the next sector along the ray's path, and the intersection check is done again. The BSP tree merely makes finding which sector the ray is in faster given arbitrary shaped sectors.

When saving as a 16 bit BMP, there are two modes most programs save in - REAL 16 bit (RGB565), and 15 bit (XRGB1555). When I'm working on the 32X, I need the latter. For the Jaguar, you'd need the former. Two more points - BMPs are always in PC format, i.e., little endian. The Jaguar is going to want the data in big endian format. And finally, the Jaguar 16 bit RGB is actually RBG556, not RGB565. Converters need to take all this into account.

Blackthorne will NEVER work... it's a 32X game.

Nope. It's software. You cycle the color palette after so much time without an input. The 8-bit computers had it in the OS, but it was still software.

Nice job! Too hard generally means no examples and/or libraries. I think you're taking care of both those here.

I think he's looking for the Dreamcast or Jaguar. I know I'm interested in the Dreamcast version if you have a date on that.

Good to hear. Welcome to the CDX Club.

Yeah, those old CD drives can sometimes be hard to find. For the Sega family, the Model 2 is the easiest to replace.

Yes, the CDX is a persnickety console. Mine is VERY picky about CDRs, but pretty decent with pressed CDs.

Heh - I had the Koala Pad and MicroIllustator for the Atari. Still have the Koala Pad...

You could use either the 68000 or Z80... you were mainly supposed to use the Z80 for Genesis music. Some drivers use only the 68000, and a few use both the Z80 AND the 68000. The Z80 was big for many companies... in the US, Tandy made a ton of Z80 based computers before finally switching to the 6809. The Z80 was huge in Europe as well. I think the main thing was companies trying to save every cent possible went with the 6502. The Z80 was powerful, but pricey, so you saw it in devices where the price didn't matter as much, like arcades and PCs. Home consoles liked the 6502 to keep the price low.