Sure, but I was also considering trying to keep component count and costs down as well.

Obviously stuff I don't know anything about. How does a wire wrap version avoid this problem?

If by experimentation you're talking about simply talking to other things using the VIAs, then sure. If you're talking about doing something to the actual CPU (add memory, add decode logic, etc.), then more surgery is involved.


Yea, I completely agree with this. When I say serial port I mean something like a generic serial port and students using (USB) adapters to talk to it. Zero reason to add USB to the project board itself.

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

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x86?  We ain't got no x86.  We don't NEED no stinking x86!

Ah, but don't forget my 65SPI interface. It handles all of the SPI shifting and can use status polling or interrupts to monitor progress. I found it quite easy to implement the ENC28J60 Ethernet module (the TCP/IP stack was a little harder). I have also used it for a few other devices. While it is housed in a CPLD that requires one-time programming, I have an open offer to program user-supplied chips for anyone who asks - free of charge, other than the return postage. The 44-pin PLCC does not require a lot of board space and there is a little room (and a few I/O pins) to add some extra glue logic too. I can help with that too.

OK, I'll shut up now

Daryl

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Please visit my website -> https://sbc.rictor.org/

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!

Another small SBC design is Halldor's - the site has been intermittently offline but is up at present.
http://www.fririki.net/6502/basic_design.html
It would be easy and desirable to substitute a clock can, unless explicitly teaching the workings of a crystal oscillator.
He's using DIL headers and ribbon cable for expansion, which will be OK for very short distances. It wouldn't be difficult to swap in alternate grounds and the necessary extra headers, if that was a concern.

Exactly. The FTDI serial to USB chip does not require any programming and the driver works in any platform.

I could have invested in Apatco's computer but I chose the Raspberry Pi and I ordered one. The reason is partly financial because $35 vs $180 and 12 MHZ vs 700 Mhz (and overclocking) and they are so cheap that I can put five backups in my closet for years to come. A reason I went this direction is because they have a magazine and I don't think the 6502 has one. The Raspberry Pi is selling out and there are many stores. The Raspberry Pi has all kinds of engineers working for it and I can buy 4 inch or 7 inch NTSC screens for it, there are cases available and I can connect it to VGA and HDMI. I can connect it to ethernet and I can put in a Wifi b,g, n dongle. It can run several languages and has become the new social and learning computer in so many ways. It can even accept a 16 GB SD card and theoretically it might be able to do 32 GB on a card. Element 14 is selling a Gert board and Adafruit sells a Pi Cobbler for breadboarding. They are basically doing everything to make it succeed and they are also doing it to teach the next generation of kids how to program and use computers. Look at all the good they are doing. All these devices are available because of people willing to go the extra mile and let the Raspberry Pi become open source and it becomes low cost as a result because if everyone charged $100 or $200 for their part, this computer wouldn't sell out..

The other trend is that hardware is dead:

http://venturebeat.com/2012/09/15/hardware-is-dead/

When you can get an A-Pad from China for $35 that can do everything and when hardware companies aren't making much of a profit on it, they consider there to be no money in hardware.

Arduino is the same. I've always been interested in electronics but never had the means and the time to get started with it. Once I bought my Arduino, I started learning Java and Python, learnt to make custom PCB and made my own UV exposure unit and a bubble etch tank from a Tupperware milk jug. I've even learnt to solder SMD and using multiplexers and Bluetooth modems. Later bought an FPGA dev board, then learnt about analog electronics, etc. I don't think I would have got into it without that initial 'push'. I don't think I could have afforded programmers and learn C just to be able to make some LEDs blink.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

With the sophistication of modern electronics combined with the ubiquitous availability of mature and robust software, for many it it far easier to bolt stuff together from modules than it is to work things up from scratch. For many cases it's simply easier to use a SoC and wire that to a battery and the blinky lights you're trying to drive.

Theory is less and less important when the off the shelf bricks do the job well enough for your applications.

Raspberry Pi is great for those who want to make a self hosting blinky light platform. Wire the lights and motors and sensors to the board, and poke and prod using your favorite scripting language, enabling a nice, zero turn around dev environment for, effectively, the price of 2 movie tickets. It is fabulously cheap.

Arduino et al is better for those trying to install it on something else. It's not self hosting, you need to build, download, execute, rinse, repeat, but the community around it is nice and high level, artists and "makers" rather than in the trench engineers. Super accessible, instant robots, etc. Arduino helps make the entire field less intimidating.

The SBC project would be interesting, but it's becoming less and less necessary for those wanting to dabble in this field. Those who want to make it a profession will pick this and much much more up during their engineering studies.

A similar phenom is happening in software, where folks stitch together libraries written by others available freely on the internet rather than implementing the details themselves, much less understanding the details of what or how the libraries do what they do. This continues up to the point of not understanding computer architecture, algorithms, data structures, etc.

Through wide availability of libraries, and the truly amazing performance of systems today that can "cover" for bad decisions, folks are finding success much easier with less understanding than has been necessary before.

This is why it is so important to understand when undertaking a project why you are doing it. If you just want to make blinky lights, a 6502 SBC is the long way around to get there today. If you want to understand 6502 architecture and programming, there's a zillion simulators out there you can use. If you want to perfect your wire wrap technique, perhaps an SBC project is the thing for you.

Of the things you mention, I think only the SBC tells you about busses and address decoding.