Re: virtual hand jive and human factors

Too many Alan's in this conversation .. I'm not sure which one of
this is directed to, but here's a few thoughts.

1. I used a 16c63 in the pendant, but there's no need to use such an
expensive one. Even a C54 will do the job. I just happen to have a bunch
of c63s laying around AND a nice development tool, so I tend to use them
for almost everything.

2. Since CNCPro DOES seem to use legal calls, I would strongly discourage
poking values directly to a memory location, as that is generally considered
"illegal". Moreover, it's unnecessary .. Int16h function 5 does exactly
what's needed in an "approved" manner.

I do know where you're coming from though .. I cut my teeth on 8080s running
CPM. When I started writing PC code on 4.77 MHz PCs, I used every trick in
the book to avoid using the BIOS for anything. Now that our computers are
oh, 50,000 times faster, there's very little reason to NOT use the BIOS.

3. Little glitch in my pendant. CNCPro uses both KEYPRESS info as well
as KeyUP ( and MAYBE KeyDOWN ) info. KeyPress codes are used for just about
everything, near as I can tell, except that KeyUp is used during fast and
slow jogs.

That is, CNCPro will begin a jog when an arrow key is pressed, and continue
a jog as long as an arrow key is pressed. Only upon a KeyUp event is the jog
terminated.

There is no good way to "legally" stuff KeyUp info into the keyboard buffer,
meaning that when the pendant sends an "arrow key" to begin a jog command, the
jog would normally continue on until the limit switches are tripped.

Thankfully, there is a simple enough way out. CNCPro seems to monitor the
ESC key at all times. When an arrow key on the pendant is released, I have
the PIC send an ESC key as well. This terminates the jog.

4. > Simon Fraser University? BC?

Yup !

Alan

--

Alan Rothenbush | The Spartans do not ask the number of the
Academic Computing Services | enemy, only where they are.
Simon Fraser University |
Burnaby, B.C., Canada | Agix of Sparta