I think you are answering his question wrongly. Yes, it is true that the 68xx processors have have more capability than the plain 6800 (more registers, more addressing modes, etc.), but they will run 6800 code. What you would have to look out for is how i/o is mapped and those sorts of things. So I think the answer is yes, the 68HC11 (for instance ) will run 6800 code, but the reverse is, of course, not true. John Hartman (NoICE) wrote: >>>Does somebody know a new type of processor that is capable >>>to run (unmodified) 6800 code? (Like for the 68HC11). >>> >>> >>Come to think of it, the HC08 MAY be upwards compatible >>(instruction set wise) with the 6800. >> >> > >Unfortunately not - the 6800 had a single 16-bit X register, while the HC08 >has 8-bit X and 8-bit H that sometimes work together. 6800 also had no >stack-relative addressing, and couldn't PUSH the X register, which lead to >some rather obscene code. 6809 was a big step up, HC11 stepped back from >there, and the HC12 is a nice piece of work. > >Do you need binary (ROM) compatibility? If you have source code, you >should be able to convert it to HC12 without a great deal of >pain. Instruction timing would be different, however, so watch those >1976-vintage spin loops. > >If you need binary (you mean you lost your 30-year old source code?) there >are hobbyists and university classes out there doing FPGA implementations >of various classic processors. You might do a search on that. > >Or Google on "SWTP 6800" - Southwest Technical Products made an early hobby >computer using 6800 and probably has some rabid fans that would know what's >available in 6800-land. > >Best regards, John Hartman > > NoICE Debugging Tools > http://www.noicedebugger.com >Yahoo! Groups Links >************************************************************** >Scanned by VisNetic MailScan for SMTP Servers. >Visit http://www.deerfield.com/products/visnetic_mailscan. >************************************************************** > |