Help with communication between PC and 68HC11 board

Hi to all:

I'm just getting back into this stuff.  I built and had working a
68HC11 board.  I have two processors:  a 68hc11A1FN and the
68HC11E2FN.  I take and replace each when I want to use a particular
one.

I had this thing working like a champ about 1 year ago, put it down,
and can't get it to communicate with the PC.  I know the chip is
working because I programmed the E2FN and upon a reset, it blinks and
LED on and off.

When I first tried to get this working, it took quite a while before
someone had me do something with PCBUG...
I remember there was something that I had to type after PCBUG at the
DOS prompt, but can't remember it for the life of me.

I've tried about everything.  I've tried different baud rates, parity
settings, xon/xoff, through the hyperterminal.  I've  also tried PCBUG
and can't get it working.
Right now I'm using CGN-1001 232 board. 
Thanks for all the assistance.

Art

mathtutoring@comcast.net wrote:

> Hi to all:
> 
> I'm just getting back into this stuff.  I built and had working a
> 68HC11 board.  I have two processors:  a 68hc11A1FN and the
> 68HC11E2FN.  I take and replace each when I want to use a particular
> one.
> 
> I had this thing working like a champ about 1 year ago, put it down,
> and can't get it to communicate with the PC.  I know the chip is
> working because I programmed the E2FN and upon a reset, it blinks and
> LED on and off.
> 
> When I first tried to get this working, it took quite a while before
> someone had me do something with PCBUG...
> I remember there was something that I had to type after PCBUG at the
> DOS prompt, but can't remember it for the life of me.
> 
> I've tried about everything.  I've tried different baud rates, parity
> settings, xon/xoff, through the hyperterminal.  I've  also tried PCBUG
> and can't get it working.
> Right now I'm using CGN-1001 232 board. 
> Thanks for all the assistance.
> 
> Art

It's been a while but here is how I remember it.  There are two pins on the
HC11, MDA and MDB that have to be in the correct state when the chip comes
out of reset.  These pins put the chip in the special test mode that enables
the internal boot rom, which has a built in downloader.  Then you start PCBUG
and when it asks if the talker is installed you say no.  PCBUG then downloads
its stub via the builtin boot loader and you are good to go.  The key is to
have MDA and MDB in the correct state to start the built-in loader.  I've
used just this setup on both the A and E version of the HC11.
Hope this helps.

Dave Rooney