[Coco] rs232/bitbanger in MESS?

[John W. Linville]

On Tue, Dec 01, 2009 at 06:18:28PM -0500, Aaron Wolfe wrote:

> I'm going to keep messing with this (pun intended) :)  Would be very
> useful to have a serial port in an emulator.

That's pretty much what that code I sent you does, although it
doesn't pretend to be a 6551.  It does however handle a couple of
addresses in the emulated address space and connects them to a PTY
on the Linux side.  I find it very useful. :-)

The MESS 6551 emulation seems to be modeling the behavior of the
6551 as seen by the CPU.  But like you, I could never see that it
actually did anything to communicate outside of the emulator itself.
I don't know how that is useful to anyone other than as an exercise
in hardware emulation, but whatever...

It probably wouldn't take much effort to take the code I sent you and
refactor it to more closely model the "user interface" (i.e. register
set) of the 6551 to that you could use 6551-aware CoCo programs to
talk to the outside world unmodified.  It's just a SMOP... :-)

John
-- 
John W. Linville		Someday the world will need a hero, and you
linville at tuxdriver.com			might be all we have.  Be ready.