On Thursday 15 September 2016 04:55:03 andy pugh wrote:

> On 15 September 2016 at 05:20, Gene Heskett <ghesk...@shentel.net> 
> > would be simplified if I could use a 'setp' parameter as
> > a 'net' pin.
> As parameters, pins, nets and "setp" are all different things I am not
> clear what you are asking here.
> If you are asking if you can "setp" a pin value then leave it
> unconnected, and it will hold the setp value, then the answer is "yes"

I'd like to "net" it to the output of another logic module, which would 
save an and2 gate in the data flow.

I already have a 'spindle-is-moving' signal which would (re)trigger a 
oneshot to give a steady signal as long as the spindle is turning. Then 
I want motion.spindle-on to trigger a second oneshot. If at the end of 
that oneshot pulse, the spindle is moving, everythings fine, but if the 
spindle-is-moving is false at the end of that oneshot, trigger a 3rd to 
pull motion.enable down for a few milliseconds, bringing everything to a 
halt before the motor, with no feedback, has been told to go 450 rpms, 
but the PID winds it up to 10 grand and destroys some more stuff.  This 
time it was the 5i25 and the bob that were blown.  But it went thru the 
grounding system and took all 3 slot interrupters out of the encoder 
too.  So it was about a $150 fix all told, apparently caused by a lack 
of a common ground between the - end of the motor's psu and the system 

So maybe do it with 2 oneshots & a timedelay?  The timedelay to make a 
startup delay of perhaps 50 milliseconds. A oneshot to convert the 
filter pump to a steady signal, Feed those to an and2, and if the and2 
goes true, fire the 3rd one to shut things down before the motor gets 
all wound up.

But, if I could 'net' the edge trigger parameters, I could do away with 
an and2 in the chain by disabling both edges in lieu of the and2.

It seems there ought to be a simpler way than 4 hal modules to do a 
spindle hasn't turned 100 milliseconds after enabling it shutdown.

I'll set that up come daytime & see if I can get the right "-not" signals 
into the and2.

The idea is to pull motion.enable low just long enough to kill everything 
and then release it.  While at the same time, being immune to the very 
short time of very low speed when the spindle direction is reversed 
while doing rigid tapping. That reversals speed is determined by the 
acceleration profiles, separate from the PID that I put in to keep from 
destroying drive pulley's and belts.

That acceleration limit3's straight line ramp works, but I'd like to have 
a limit4 whose characteristic output for a step input was a 'sine 
squared' ramp.  But we "don't hardly got some more of those". :)  It 
would go a long ways towards de-jerking the spindle.

Thanks Andy.

Cheers, Gene Heskett
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>

Emc-users mailing list

Reply via email to