HC11 disassembler wanted

[Roger Heflin]

On Fri, 25 Sep 1998, Ludis Langens wrote:

> Joe Boucher <BoucherJC at lmtas.lmco.com> wrote:
> > I am definitely not an expert in this area.  I'm just parroting something I read.  You
> > might try using a 6809 disassembler on the code.  My understanding is the 68HC11 is
> > based on the 6809 and the 6809 instructions are a subset of the 68hc11 instructions and
> > you might have better success than you might think.  There are 6809 disassemblers
> > available for free.
> 
> HALT!  Go directly to Radio Shack.  Do not pass IRQ.  Do not collect
> $200 of 6809 tools.
> 
> The 6809 is different from the 6800/6801/68HC11.  It was (one of)
> Motorola's upgrade path(s) from the 6800 - in the same way that Intel
> went from the 8080 to the 8086/8088.  In both cases, old assembly source
> code could be mechanically translated to the new design.  But neither
> one was object code compatible.
> 
> The most famous use of the 6809 is the Radio Shack Color Computer
> (CoCo).  The most famous 6809 operating system is OS-9.


Incorrect.  The every 6809 instruction is in the 68HC11, with the same binary
opcode.  The 68HC11 has extra I/O ports and some extra commands not found
in a 6809, but any 6809 code should work on a 68HC11 chip.  The 68HC11 is
an upgraded improved 6809, the 6809 is an upgrade from the 6800 and the
68HC11 is an upgrade from the 6809.    The 6800 and the 6809 were used in
alot of embedded designs, and the 68HC11 added more features and more of
the neccessary instructions and features for Motorola to keep this market.
The primary difference between a 6809 and the HC11 is the HC11 has several
extra instrutions and alot of mask options for A/D D/A, I/O, and other useful
stuff for the embedded market.   


Another comment: to the person that could only find a simulator for the
68HC11, the simulator has a disassembler in it and will work just find to
disassemble to code, it just takes a few (10-20) more keystrokes to get
the job done, but it works quite well.

				Roger