selgus

I've bought a bunch of XEGS motherboards from Best recently, for the custom chips, and he has been very responsive and quick to ship. I often do wonder how much stock he actually does have remaining. I bought 4 motherboards and asked him how many he had left (so I could figure out how many I should get before he ran out), but his reply was 'I have plenty'.

I really like the MyIDE system, as its very simple design (complexity-wise), pretty straight-forward dealing with from the BIOS-side, and speed-wise, perfect for a handheld.

I have started working in CAD with the case design now. The keyboard is modeled after a scaled down version of the 130XE keyboard, with a few modifications. I added the F1-F4 function keys from the 1200XL design to the matrix and have them on that first row. Also the joystick D-PAD is on one side, and the fire button is on the other. I designed the joystick as two separate small PCBs, so they could go on either the left or right sides. I've been working on the BIOS, to handle all the CompactFlash support, along with it's other features (i.e. built-in debugger). I've also been removing things from the standard BIOS that are just not supported on my 67XEP (like the self-test routines, cassette, printer, paddles, PBI, international character-set, etc.)

I just recently got back my prototype PCBs for my Atari Portable I've been designing. It is based on the Atari XEGS schematics and utilizes all the original custom chips from the XEGS, along with modern SMD components for all the other glue and functionality. I am calling it the ATARI 67XEP. The form-factor I am going for is something similar to the Nintendo Switch, but with a keyboard and tilted LCD display. It includes a built-in MyIDE CompactFlash card interface by Mr. Atari, and a custom BIOS (started from the Revision 4 XEGS OS Source code). It uses a LiPo for power, and I've designed another small board that goes inside the case, that provides a DC boost converter, USB charging and RS-232 communications to a PC. The system has a built-in joystick/fire button for joystick 1, and a mini-DIN7 port for the joystick 2 port. I'm using a 4.3" LCD display, but as I'm finalizing the case design (taking influence from the 130XE case), I am also going to experiment with a 5" display. I have some more parts to arrive, but starting to assemble it now.

My first system was a timeshare back in high school, which was a DECSYSTEM-2020, which I was programming in MACRO assembler. It had 36-bit registers and TTYs to interface with. I learned a lot about programming and system on that hardware. Shortly after that I learned 8080 assembly on the Compucolor micro, which had a built-in floppy drive and color monitor. I wrote a defender clone for the Compucolor, then a version of pac-man. These systems started me on my path for working in assembly language, that I still have not overcome..

Received my card when I got back from Sweden, and looks great! Thanks SainT! B

Modified another one of my Lynx-II consoles last night, same excellent results.. Atari-Lynx-II-Mod by brett.bourbin Atari-Lynx-II-Mod-LCD by brett.bourbin

Added the PLCC plug to the other end so connect to my eprom programmer. I will probably add hot-glue all around the PLCC connections to minimize any sort of wire breakage/issues.. Atari-Lynx-Cable-PLCC by brett.bourbin

Well I reconsidered and made a cartridge port connector to allow programming of my lynx pcbs after the eproms are soldered. Just waiting for my PLCC plug arrives to attach to the opposite end.. Atari-Lynx-Cart-Connector by brett.bourbin

I too would be really interested in hearing how this compares on real hardware speed wise. I don't totally trust the outputs I get on at the emulator I run on the Mac.

For the number of carts that I would ever make, I'll stick to programming the eproms and soldering to the pcb. Takes very little time at all with a hot-air station and is a simple solution IMO. Anyways, this will hold me for now while I do work on software. Keeping my focus on the general 3d scene rendering and the right balance between the SUZY and CPU. Thanks though for the input.

Think more like the Eidolon, where it takes place inside of a cavern..

For the vga connector cut-outs on my Lynx I and Lynx II McWill upgrades, I just used an xacto knife, and took off small layers after layers from the top on downwards. While do it I kept test fitting the vga connector until I had the right depth of material removed.

What I mean by fractal rendering, is I am using a midpoint subdivision algorithm to build the display, similar to how the Lucasfilm Games group did back in the '80s. Actually the Suzy plays very little in this part of my application (it is used to draw the columns), as they are very specific, optimized 65c02 assembly routines to fill the frame buffer, using a y-buffer.

Thanks. As for the game, I'm not saying too much about it yet, until I have enough to show.. but it uses a fractal rendering engine, is first-person perspective, and my goal is to also include multi-player..

I had a bunch of PCB manufactured for my Lynx Cartridge and built up a test one with a socket for the EPROM (plan is when I make my game, I will solder the OTP EPROM directly to the PCB). I belt sanded the edge of the cartridge connector to give it a more tapered edge.. I will probably build a jig to make a repeatable, consistent angle when I am ready.. Atari-Lynx-Cartridge-PCB by brett.bourbin

Yeah, I installed the screws after doing some testing first.. wanted to make sure everything worked before mounting the display. I did have a question why the display had notches instead of full holes for the screws? When I was finalizing the assembly it is a bit.. awkward, getting them aligned properly. Having a screw hole in the display that matched the hole in the Lynx PCB would have resolved this IMO, though maybe there was a different issue you were trying to solve with the current implementation?

And just finished doing my Lynx 1 model with it's new LCD display. Still very simple to install..

Did one of my Lynx II McWill LCD screen installs today.. I still need to figure out how I want to mount the VGA connector on the side of the case, though will probably just use hot-glue as recommended. I did also remove the existing video ribbon connector to solder right through the holes. Screen is now bright and beautiful.. Beautiful work Marco!

Got my two kits yesterday, but won't have time to install them until next week when I return from my business trip. Beautiful boards!

So I have been working with ca65 assembler from the cc65 package as my macro assembler for the Lynx, but am starting to look at possibly changing to Macross. Now Macross was an assembler written by Lucasfilms back in the late '80s for their assembly language projects on the 6502 and 68k. It did share some structured programming constructs like you have in C (i.e. do-while, if-then-else, do-until, etc.) so it might be a good middle road for you to look at. Last year they open-sourced the code to Macross so you can build it for whatever host you are working with currently. I was going to add 65c02 support to it, so I could use it on the Lynx, but it looks like someone already beat me to it.

Found my old SEGA Genesis hardware, here is a pic: Sega-dev by brett.bourbin On the left is my SEGA hardware I used to write games and the one I developed my debugger for (GDDT). It is strictly a 68K assembly debugger and command line interface driven (i.e. I didn't create a Windows application). To the right is an Accolade development card. This is the board they used to create SEGA Genesis games when they were not licensed developers and reversed engineered the system. Sort of a neat artifact from the '80s. Below is a Psy-Q SCSI card that was used with IBM-style PCs to connect to Psy-Q SEGA development boards. I couldn't find my old one of these in my house. I did find some of my code for my GDDT debugger, which supports breakpoints, register manipulation, 68K disassembly, single-stepping, etc., though isn't much use unless my monitor EPROM code is ported to whatever hardware you are using on the actual SEGA to communicate.

That's pretty cool to have Peter notice and respond to your hard work! Congrats! Personally I'd continue with the pathway of the two-player game, and get sounds going before the AI also.. Remember you are accomplishing stuff the Lucasfilm Game team didn't think possible in the 80's. I talked with David once and he said if they could have done it on the VCS they would have.

I used to develop on the Genesis back in the day.. my friend made an SRAM card that would connect to a PC via a parallel port (which really don't exist any longer on PCs) and I wrote a 68K debugger for it, along with libraries for the games I was doing. I probably still have that code in my archives somewhere, if it would be useful.

I was in the same boat as you when I decided I wanted to write something for the Lynx a month ago. I had done some stuff for the 2600 a few years back, but my real 6502 coding dates back to the mid '80s. Don't worry, you will pick back up the 8-bit instruction set and that old knowledge/tricks you've store away from year's past. I would recommend staying with assembly as the macro assemblers are so much better these days, can be used to cross-compile to the 8-bit targets and will give the best utilization of CPU cycles/memory footprint (at the cost of implementation speed). You can also use one of the 6502 C compilers too, and have it output the assembly so you can see what it would generate. I used to use that when I was doing Nintendo 64 and Saturn work to see how much I would need to actually code in MIPS and SH2 assembly.