Gcode pause command?

[mark296]

I would like to know if there is a gcode pause command that will pause a program half way through until a key is pressed? I am cutting several pieces of wood that have a long travel path from one side to the other. When it gets done cutting I would like it to pause until I take that piece of wood out and put another in. Then I can have the program run backwards to get to X0Y0Z0 Home replace the piece of wood and repeat the process. Is this possible? I am running Mach2 on Xylotex board.

[mark c]

M0 will always stop, M1 will stop if the optional stop switch is on.

[imwllc]

M0 should be program stop, sometimes M02 also is, if you have an optional stop button you can put in an M1 for it to stop there

[Al_The_Man]

M01 is Optional stop, when this is seen, the program halts and waits for a cycle start. You would have to check to see if Mach2 has this.
Al.

[Bear]

mark ,
dont know of any command code to run program backwards.
Impossible I Say
Bear

[ger21]

Just hit the feedhold button to pause as long as you like.

Are you saying you're making one cut from one enfd to the other, pause, change board, run back to the other end, pause, change board? If so, I'd write the code to go from one end to the other. Hit the feedhold, and change boards. Hit cycle start to resume. At the other end, use an M30 to end and rewind. Switch boards and hit cycle start again.

[Al_The_Man]

The only thing with feed-hold, its indeterminate, also you have to be on the ball and remember when to hit it, with the M01, it is a defined stop at the end of block, move etc.
Al.

[Ken_Shea]

Mark,
What you want to do is possible but not with having the program run backwards, as was pointed out that cannot be done.

What you would need to do is create two tool paths with the first going one direction and the second going the other. With a M00 at the end of the first tool path.

MOO is a good choice, it is more accurately described as "absolute stop"
which not only stops program execution and then increments to the next block, it also stops the spindle so you can safely put another board or rotate part, stops coolant (NA in your case and happily waits for the "Cycle start" button to be pushed to continue on.

Here is a NC example.
%
O0000
T5 M06 (PROFILING .250" CARBIDE END MILL)
G90 G80 G40 G54
S4000 M03
G43 H5
/M08
G00 X-11.05 Y-1.525 Z0.2
Z0.1
G01 Z-0.125 F10.
Y-1.575 F20.
G03 X-11. Y-1.625 I0.05 J0.
G01 X1.
G03 X1.05 Y-1.575 I0. J0.05
G01 Y-1.525
G00 Z0.2
M00
M01
G90 G80 G40 G54
S4000 M03
G43 H5
/M08
G00 X1.05 Y-1.525 Z0.2
Z0.1
G01 Z-0.125 F12.
Y-1.575 F24.
G02 X1. Y-1.625 I-0.05 J0.
G01 X-11.
G02 X-11.05 Y-1.575 I0. J0.05
G01 Y-1.525
G00 Z0.2
M01
M30
%

[mark296]

[QUOTE=Ken_Shea]Mark,
What you want to do is possible but not with having the program run backwards, as was pointed out that cannot be done.
QUOTE]

Thank all of you for your replies.

Ken_Shea, I did not want to run the program backwards. I will program a second tool path that will run backwards but did not know how to pause or stop the program in the middle of the two programs until now, Thank you.