6809 CPU card

[Alan Cox]

The 6809 CPU card is also passing basic testing so I've uploaded it to Hackaday as well.

https://hackaday.io/project/172025-6809-cpu-card-for-rc2014

Not sure what I'll run on it, the 6809 world has so much choice.

As with the 6808 there isn't a lot to it. It's the same basic motorola/zilog bus conversion with a 74HC00 and 74HC688. I'm really happy it worked first time however because the board has no vias, and I'd have been upset if I had to add one to fix it 8)

Alan

[Greg Holdren]

OS-9?

Greg

On Thursday, May 28, 2020 at 11:17:09 AM UTC-7, Alan Cox wrote:

Not sure what I'll run on it, the 6809 world has so much choice.

Alan

[David Richards]

Alan, as you say so much to choose from.

Many OSs here; https://github.com/nealcrook/multicomp6809

Nitros9 seems very usale on my multicomp09.

and some simpler ones here too; https://github.com/6809/sbc09

The tiny basic and Forth files in the sbc09 I have used for testing a retroshield 6809 in preperation to running some of my own old 6809 eproms.

Interested to hear what you decide to run on your own board.

Kind regards, David

[Alan Cox]

Nitros9 seems very usale on my multicomp09.

and some simpler ones here too; https://github.com/6809/sbc09

Nitros9 seems very complicated to set up in the first place so I shall probably start with CUBIX once I have all the bits and have built the memory card so I can have ROM high and page it out.

Alan

[TonyD]

Alan, great new on getting 6809 working. One of my favourite micros.

Tony

[Alan Cox]

On Saturday, 30 May 2020 14:26:46 UTC+1, Alan Cox wrote:

I've finally had time to get back to RC2014 stuff. I gave up on the memory card. My 128K RAM and 32K EEPROM + decode design came out little less complex than just using the existing 512K/512K card so I used that instead. As it maps the first 16K of ROM everywhere it works with all sorts of processors.

I've pushed an initial CUBIX ROM to my github tree and I have CUBIX running nicely on the system. It's a very clean OS design and only needed a few hundred bytes of 'BIOS' type stuff and bootstrap code to get it going. Although I built my extra firmware with lwtools it's basically self hosting so if and when I get time I'll move the bits over so it can build itself.

https://github.com/EtchedPixels/RC2014-ROM/tree/master/6809