I just started getting into programming on the 6809, which looks to have be designed by the same developers as the 6502. Wonder if in a few years I'll be able to do the same :)
Edit: I'm reminded of OS-9, but I don't believe that matches the bullet points from the article
MOS took engineers from Motorola who made the 6800 chip, cloned it and MOS 6501 was pin compatible with the 6800 and the 6502 changed two pins. Motorola sued and won over the 6501 but not the 6502.
The 6809 was a 16 bit chip IIRC. TRS-80 COCO used it. It was the original chip to be used on the $600 Macintosh project until Steve Jobs took it over and changed it to the 68000 CPU.
6800 cost $300 and 6502 cost $30, guess which ones the 8 bit video game consoles and computers wanted to use?
I'm pretty sure the 6809 is still considered a 8-bit processor. You could treat 2 of the 8-bit registers as a 16-bit, but it was still 8-bit registers.
I had a friend in high school who upgraded from the TRS-80 COCO to the TRS-80 COCO2 and offered me his old computer. I already had a Commodore 64 and I told him no, to give it to another friend who didn't have a computer yet. I should have taken it so I could run OS9 on it.
Edit: I'm reminded of OS-9, but I don't believe that matches the bullet points from the article