loconut

I hadn't considered tearing apart a Lynx (I wouldn't part with mine)- but maybe I can find one with a broken screen. I'd say it'd be a pretty cool step to replace the LCD / circuitry and CPU with an FPGA- but I'm concerned about the number of connections out of the CPU to RAM, Suzy, Mikey, etc. I have a wirewrap board for my FPGA kit, but I'm not sure I'm patient enough to try and get memory (albeit relatively slow) both wired and working that way. It's probably going to end up harder just because we'll have to do it all in the FPGA at once. Hopefully we can cobble together a text mode and do some diagnostics on the CPU / LCD with that before needing to implement the rest. I think we can still probably take it a piece at a time.

Sorry to bump this age-old thread, but I'm interested in getting a group of people together to work on an official design. I'm definitely in favor of the SuperLynx approach and would like to see (if possible) the primary CPU as a 65816, 65GZ032 (or something unique we create) with whatever modifications (if any) that would be needed to make it 100% 65C02 compatible versus the "mostly" compatible I read about in the documentation from WDC. We could set up an OpenGoo project (I'll host if you'd like) and/or a Wiki. I'd eventually like to make a handheld FPGA with a screen and everything, but for now just working with assorted dev kits would be fine. Is anyone interested in trying to make some real headway on this, starting with some discussion and planning?

Alright, I finished my other project and am now starting to get geared back up for this project. Anyone that's still interested should get together via email or something and try to get something organized. My preference is strongly in favor of VHDL- is that going to be an issue? P.s. I don't recall if I mentioned it- the development kits I own are an Altera DE2 (Cyclone 2 w/ 35K LEs, a 10-bit vga dac, and a smidge of SRAM and SDRAM) and a Xilinx XUP-V2P board (Virtex II Pro, DDR socket with 512 MB installed, and an 8 bit VGA dac).

I hadn't heard of the GamePort, I'm going to have to increase my knowledge on that. That sounds like a pretty killer plan. I'm fairly new to computer architectures so I have a lot to learn. I've mostly done logic driven designs and pipelines, not very much architecture. I'm knowledge hungcy and will do my best to make the curve It sounds like we'd have to keep the palleted graphics in there- could we do a compatibility mode so new games could run full color and old games could stick to their 16 swatch pallete and 16 bit color limit?

I'm pretty sure Western Design's 65C02 is rated at 14MHz. Yeah, they claim it'll do up to 28 MHz IIRC. The one I had found on jameco was only to 4. All that was cleared up when I called them- apolofize for not clearing the air on that one.

I have some plans to create a "SuperLynx" which will basically have widened busses (32 bit?), ditch color palletes in favor of true color, and bump the resolution to 720x480 (better ideas?). The games will be incompatible of course, but conceivably, if the details otherwise remain similar would lend for easy porting. It probably has no real use, but it seemed like a fun idea. I've always been interested in game systems and after studying up on Suzy, I'm even more hooked on expanding that knowledge through experimentation. For now, it looks like I'm committed to finish another project first, but expect to start in on this in parallel - though with decreased time slices and resume full bore next semester. (I'm a non traditional student at ISU and work full time).

I'd like to buy one or two blank carts with or without an EPROM chip. I'd like to buy one that I can wire up to an FPGA to pretend to be a cart and another I'd like to be able to program games onto. Does anyone know a source for these?

if you end up with a totally dead one and would like to desolder the cart connector and send it, I'd pay for your troubles.

update: spoke with WDC and hopefully am getting a 65C02 core to use under NDA. This will at least let me get it working for my class project and you can either hook to an external CPU or implement your own later, but Mikey and Suzy would at least be taken care of. Again, I won't be able te release the CPU core, but hopefully youll be able to just drop in one or hook to a physical one via IO.

One more question about the design of the Lynx With the cartridge reader sharing pins with the buttons/pad, how does pushing a button during a cart read not mess up the data? Wouldn't the pull up resistors end up giving you 1's wherever a button was pushed? (if during cart read)

I have a DE2 board that I own handy, which should be enough, but I also have on loan a stratix ii board that I can use. I'm going to be doing this all on a dev board for now- if it all works out, perhaps I'll fab a board. Cart interface will have to be via the santa cruz connector on the stratix board or the expansion ports on the DE2 (I have a santa cruz adapter for that). SRAM on the DE2 is exactly 64K for system ram- the rest can be done in M4K for col/vid buf, etc. clock is 50 mhz on DE2, mult by 8, div by 25 in the pll gives 16 MHz easily. also, can use the VGA and audio chips on the DE2 as well. edit: changed spartan to stratix- i always mix them up. I probably can get a couple xilinx boards, but I'm more familiar with Altera offerings.

I'm not that great with a caliper, but these were fairly repeatable for the couple carts I checked cart width: 57.12 mm / 2.249 in (for Zarlor mercenary at least though califronia games is 5 thousandths bigger (57.13 mm) and Im guessing the spec is actually 57.15 mm / 2.25 in) cart thickness (across contacts): 2.50 mm / 0.098 in (probably supposed to be 2.54 mm / 0.1 in) cart thickness (across prom square): 2.63 - 2.75 mm / 0.1035 - 0.1075 in (depending on cart) pin pitch (very approx) 1.4 mm / 0.056 in anyone know of a connector part number I can order? It looked like a PCI slot or PCIe x16 slot might work by eyeball anyway. edit: PCIe x16 is the only one wide enough for the cart, but it appears card thickness is a max of ~1.5 mm / 0.06 in from a scale drawing which wouldn't be wide enough. It also appears that pitch is 0.8 mm / 0.03 in, not 1.4 mm. Bummer. This is all interpreted from a couple dimensions of a scale drawing and measured on screen to convert screen size to real size so theres a margin of error- any reason to think I'm wrong. edit: s/foirly/fairly - preview preview. doh. p.s. have new dvorak

I'm working on building an FPGA based Lynx, and have read all the handy specs and understand the Suzy chip pretty well at this point, but the one thing I'm running into is that there are about two 6502 cores available, and one 65C02 that is incomplete. The better looking 6502 takes an extra clock cycle for most ops. Interfacing a real 65C02 doesn't seem to be an option since all of the real ones seem to be 4 MHz max. How did Atari/Epyx get it to run at 16 MHz? Smaller feature size/fab tech? Anyone experienced able to speak to this problem? Are any of the 65C02 specific opcodes actually used in the lynx or would a 6502 work? My guess was not. Thanks in advance. Meanwhile I'm going to see if I can create Suzy's VHDL. P.S. still need to know what I can use for a lynx cartridge socket. edit: typos everywhere! I'm having a bad day

I have an Atari Lynx- will it work for that? I remember those cables. Do you have more of them? I'd like to paypal you or something. Also, how do you know which end is pin 1 (GND) and which is 34 (SWVCC)?

Looks like the type of thing you see whenn the tension cliys on an LCD are loose- for the kind of screen that has those rubber strip compression conductors - or when a couple wires have been damaaged. I've never seen the inside of my lynx, so I don't know how the screen is hooked up. Might be worth taking apart and tigthening everything.