After how many years - have I found another bug?
VR3.042.040

Copy the program below. Turn single block ON
Start the program and observe that it single steps a line at a time with the start button (single block).
While it's moving hit FEED HOLD.
Wait for it to pause then hit START.
The single block is not observed even though it's still activated and the program skips right to the end.
It keeps moving too. I'm not too sure where it's going.
It no longer seems to be executing a line at a time either.

Anyone know what's going on?

G1 F10
G1X 0 Y 0.075
G1X 1 Y 0.075
G1X 2 Y 0.0749
G1X 3 Y 0.0748
G1X 4 Y 0.0746
G1X 5 Y 0.0744
G1X 6 Y 0.0742
G1X 7 Y 0.0739
G1X 8 Y 0.0736
G1X 9 Y 0.0732
G1X 10 Y 0.0728
G1X 11 Y 0.0723
G1X 12 Y 0.0718
G1X 13 Y 0.0712
G1X 14 Y 0.0706
G1X 15 Y 0.07
M30

Interesting, HERE when I run your code and feedhold in Single step mode. THEN cycle start to resume the A AXIS takes off to somewhere while the X axis resumes at a snails pace (;-) NOWHERE is there any A axis code

Interesting, (;-) TP

Tp, are running a ESS?

TP:
Note the quick question by Johnny above  and  I'd like to know:
What version are you running?

Sage

No I am not I am using the LPT.

(;-) TP

After the feedhold press Stop then press Start and see if it works.
Hood

Hood:

Well that does seem to work but but that would not (and was not) intuitive. Pressing stop at any other time abandons the program (I thought). Knowing that I would never press stop when I know I want to continue.
BTW I note that pressing stop (other than when in feed hold) also rewinds to the beginning of the program. I've never noticed that before. I usually press stop AND rewind. May be that's an option somewhere. If found all of these issues on a fresh install on a new machine.

I never experienced it but what of the A-axis move (mentioned by BR549) with no A-axis code? That's really weird.

No I'm thinking this is just another wacky bug.

But we'll be rid of it with the introduction of Mach4 

Then we can chase all the new bugs. 



Sage

I think it is a bug and I am sure there has been a problem with it for quite a while, certainly seem to recall  mention of it. Pressing Stop is not ideal but it does seem to work in your code, whether it would work with other code I have no idea as I only tried to find a way around your problem for you and thats what I came up with.
Regarding Terry's A move, I tried to replicate it here but couldnt but then again he is likely using a different version than I have loaded here.

Hood

Just out of curiosity I retested with the same code just now. SAME results, when you press cycle start the A takes off to somewhere and the X crawls along very slowly. NO A axis code involved.

V.067

(;-) TP

Oh well, I will try and see if I get the issue with that version but wont be surprised if i do as 066 and 067 have a lot of issues for me.
Hood