6502.org

It me! Honestly, of the X16 had existed 3 years ago, I probably would have just bought one and missed out on a career as an electronics hobbyist! I can't say I'm sorry things have turned out as the have. Now that I have a few basic construction skills the kits seem less appealing.

The one thing the kits do tend to have is immediate video capability, from a microcontroller or something, but that's just what I wanted to avoid anyway, so it all works out.

I suspect that those of us 'of a certain age' started this game before the personal computer - as a combined unit with an integrated keyboard, processor, and display - was even a thing, or if it existed cost as much as a second hand car. Even after a career in electronics I still hanker to recreate the thrill of putting together a system and having it work.

I'm tempted to hack something together that includes seven segment LEDs and nasty tact switches *just because I can* and for the fun of it; for the day job - even though it's dealing with designing and programming bare metal ARM systems - I have an entirely different set of priorities and challenges. Fun for the user isn't part of it; he shouldn't need to know anything about computers to use my designs.

There's a non-obvious issue with modern single-board designs: input and output has got simply too complex to manage cheaply. When I started this game, one could purchase any number of keyboards with serial or parallel outputs; one could easily knock up a video display to output PAL or NTSC. But now? Tried to buy a keyboard that isn't a cheap USB part? Tried to find a display that uses something other than HDMI (or its equivalents) as an input? The only practical way to get something into and out of a single board computer is via a terminal... which, for me, takes away the fun.

As an aside, someone up-thread mentioned people being shunning the 65816... I'm not even using the extended 65c02 instructions on my SBC, even though there's a WDC part in the socket. Nothing against the other updated parts, but it's not as much fun for me. Horses for courses I guess.

Neil

I had seen your GameTank sometime in the past but either didn't look closely enough or thought the IDT7xxxs were FPGAs (which I've been trying to avoid).

That's very cool device, particularly using a second 6502 to do the audio processing. Also very nice to see an AD7524 for the video output - I had, again, wrongly assumed a micro-controller or FPGA. I'm glad you posted, I had completely forgotten.

This is a barrier to entry, without a doubt. However, I don't think it's quite as bad as you describe. At least 3 of my vintage computing books assume that a keyboard is unavailable and the reader will have to build one. That's still an option with the ready availability of mechanical switches, keycaps, and such. There are also still plenty of PS/2 keyboards out there. Buying and restoring old Model-Ms the way I do may not be for everyone (It's kind of an expensive route) but there are also plenty of NOS cheap membrane PS/2 keyboards out there.

Finding a display can be a more discouraging project. New PC monitors are probably just not going to work, at least not without using an unpalatably powerful microcontroller to interface to it. However, both my TVs have composite inputs (!), and one of them is only 3 years old. There are also quite a few LCD panel displays out there designed for use as automotive cameras and security monitors that have composite and VGA inputs. Still, for the real retro experience you can't beat a CRT. I don't know of any place that's making CRTs still, but surplus PVMs from news vans and video editing rooms that have "upgraded" their equipment are all over the place. A few $100 for keyboards and TVs might seem excessive if you remember when a new keyboard was $8 at WalMart and you could get a mini TV / VCR combo at Circuit City for $50. Then again, I know a guy who collects shoes and doesn't blink twice at dropping $300+ for a single pair.

Anyway, to summarize, the easiest two options are definitely "use a serial console" and "use a custom modern I/O controller like the VERA." The alternatives can be more expensive or more labor intensive. But they can also be more fun!

> an unpalatably powerful microcontroller to interface to it

Like many choices, this is a matter of taste! Some people are very happy to connect a retrocomputer to a modern display using some modern intermediate.

Are any of the microcontroller based terminals worth consideration?

Yep. My personal keyboard at the house is PS/2, all of my desktop computers at the house have PS/2, all of our work desktops have PS/2. They are still selling new PS/2 keyboards on NewEgg, Amazon, and Walmart! And incredibly easy to interface.
Same here. Another (relatively) easy one is VGA, which is practically all that works on our projectors here at the college. All of my monitors have a VGA port on them. Most of my desktop computers still have VGA either built in or on the video card, but all of them can be converted to VGA with just a DVI-to-VGA cable, not even a box! I also bought a VGA-to-HDMI box and it was very simple to use, and worked the first time with minimal issues.
I completely agree Paganini.
A lot of the fun I had making my board was in the video display side of things. I'm happy to have gone down that road, and succeeded.

Thanks!

Chad

This one works well: viewtopic.php?f=4&t=6106&hilit=VT100

Hey all! I have been lurking here the past couple days and saw the Dodo mentioned so I thought I would chime in! It is still alive and in fact I have done some work related to it the past year or so. I couple of updates:

1. I re-wrote the online playground and it now supports WebSerial so it can flash straight to Dodo without installing any plugin. This is a pretty exciting development for any type of system like this to make it work much better out of the box. https://play.dodolabs.io

2. Dodo is now supported by llvm-mos (my brother did this work)!! There is a binary for it in here: https://github.com/llvm-mos/llvm-mos-sd ... tag/v0.5.1

The online playground still uses cc65, but llvm is much better. I intend to make this an option at some point.

Cheers!
-Peter

That's great!

Happy to hear this! I have the github followed, but I hadn't noticed any updates in a while...?

Here is the new playground: https://github.com/peternoyes/dodo-playground-vue
It uses WASM for the 6502 emulator

The llvm-mos code is upstream in that repo

Here is a 6502 kit idea: You can buy kits on eBay with collection of IC. Here is $10 + $6 shipping for "Barebones/minimal 6 chip 6502 computer IC kit". I just ordered one, it says "118 sold". Yes, I understand 6502 from eBay is particularly problematic but this one is Rockwell R65C02 which tends to be less problematic. The rest of the kit should be OK.

The idea here is to design an open-source pc board 100mmX100mm that'll work with this set of IC. It is cheap to order pc board and combine with the eBay kit to build a economical 6502 kit. I'll wait for the kit to show up and make sure they work, then I'll post a design challenge for a 6502 SBC using this kit. 118 kit sold, there MUST be a number of people have designed with this kit already.

Bill

PS, I have done this before: Almost 4 years ago I notice the same seller were selling a simple Z80 kit for $7. I bought one and designed a Z80 SBC called Simple80. That kit is still available almost 4 years later, 102 sold. I order two kits a month ago, built both up and both worked just fine.

Well, as it happens, I'm currently playing with such a design - though caveat: mine requires a 74HC04 for the oscillator to work as designed. From the chips in the pack, it looks intended to be used with Grant Searle's minimal design - though I don't know what the LS07 is for.

Fits nicely onto a half-eurocard (80 x 100mm), I had it made by JLCPCB who deliver quickly into Germany, even on their slowest/cheapest mail.

Neil

There are a few 'public' PCB layouts for Grant Searle's 6502 design on the EasyEDA site. I think you could use most of the parts in that kit plus a few more bits and bobs. Here's one design (see below). Bring the design into EasyEDA and get the once-per-month $8 discount to get 5 PCBs from JLCPCB for almost free ($1, using the 'economy' shipping method).