Re: Re: Re: Re: EMC Newbie

>Message: 2 Digest Number 522
> Date: Fri, 09 Jun 2000 23:43:14 -0500
> From: Jon Elson <jmelson@...>
>Subject: Re: Re: Re: EMC Newbie
>
>
>
>Ray Henry wrote:

<snip>

>> -----------------------------
>> THE LINE OF G-CODE THAT SHOWS
>>
>> That line is modal but it is the product of the look ahead feature of
>> the
>> interpreter. It shows the last set of values as far as it has read.
>> It
>> DOES NOT show the values in force for the currently executing line.
>
>And, of course, the modal parameters in effect were always shown
>correctly.
>This was necessary, because if you backed up to a move like X1 Y2 that
>was
>expected to be a linear interpolated move (G01), but the line you
>interrupted
>was a G03 (circular arc move) then you'd get an error about no IJK
>specified.
>You'd look at the program and realize you needed to explicitly specify
>G01
>in MDI mode, and then it would take off.

<snip>

>The display of modal parameters and feed rate from where the interpreter
>is reading ahead rather than what is happening now is a REAL
>shortcoming,
>and one of the truly "ugly" things about EMC. It is a really schizoid
>sort
>of thing, that the position displays show where the machine is NOW, but
>much of the other on-screen info pertains to what will happen at some
>arbitrary time in the future.

Yea and that arbitrary time in the future is usually the last line in the
part program. I've been working on that some in connection with my new
gui. Since I have to parse the currently running line to color a backplot,
and read certain lines in order to run subroutines, I thought I'd go ahead
and create a modal machine model in tcl that updates near the start of the
run of the next line. Such a thing would be okay for viewing a running
program.

BUT such a thing would be a hazard if we included a pause, do something,
then restart because the values displayed may not be the real values that
will be used by the emc interpreter to formulate the next batch of commands.

Ray