or write an arc in mdi
that just tells you what EMC does
and I'd be rather astonished if EMC doesn't do what the docs say
well that's what petev said - that emc's docs are wrong
apparently the CAM software allows you to specify "center to start" or "start to center", and that might be ambiguous, or just plain wrong.
either way is better than looking at the cam input and emcs result and ignoring the g-code, and then saying EMC is wrong
going from "the cam makes me set a surprising setting before it works right" to "emc's docs are wrong" is quite a jump, that's all I was saying
in that case, we're saying the same thing, just proposing different tests to see what the truth is
I just permanently screwed the DB25 breakout thingy you gave me to the lathe. I figured it would be nice if I could unplug it from the driver box.
the board that had green plastic DIN rail mounts?
well, the way I would interpret things, it sure seems like the cam labels the vectors backwards
cradek, did u get to testing the auto tune?
not quite yet - maybe in a few more days
I'm getting close to having this together
we want photos!
you'll see it in a few weeks...
what happened that it got all torn apart?
we want photos NOW!
did you decide to change motors or something?
it was too simple and straightforward (and working) before
good reason for an upgrade ;-)
now I'm going to need another of those rare beasts that is a fully wired straight-through parallel port cable
you're not actually using it to go from parport to anything are you?
its going from drive box to machine?
one from parport to box, one from box to lathe
the pluto is now inside the box?
what connector on the box?
don't cross them up, that would be bad
(is motor power going thru the box-to-lathe one?)
I may use a couple pins
its kinda late to mention this now, but would using centronic style SCSI connectors have given you a better chance of getting properly wired cables?
it's only a tad too late. That was my plan until I saw how easy it would be to do the lathe end using this breakout thingy
if finding the right cables is hard, why not get some round ribbon and IDC connectors from digikey?
db25 for PC to pluto, and centronics for box to lathe
petev: molded and shielded cables are "nicer" than homebrew IDE ones
yeah that was my plan like I said
the round ribbon is shielded
and the bolt on covers are not that bad
wish I had a breakout thingy
although personally I don't like ribbon for power stuff, the wires are usually 26GA or even smaller
yeah, I wouldn't use DB25 pins for power either
cradek: I wish I had sent you the cable that was inside that SCSI box
it was two 50 pin (IIRC) centronics, with about 4" of ribbon cable between them, with a 25x2 0.100" IDC connector in the middle
there's some chance I could find one of those here - but still no nice screw terminals
thats not a breakout though - its really nice to be able to screw wires down
I even have a centronics-to-db25 cable here, but those are wired very strangely
very strangely as in less than 25 distinct wires?
and various things tied together I think
seems the actual pinout doesn't matter since you have a breakout, but if it doesn't have enough conductors...
didn't you pick up a mated pair of MS connectors at the fest?
but that still has the "no screws" problem
I think I need 22 wires altogether
8,4,4 for encoders, 4 for motors, 2 for home switch
that includes both motors and encoders doesn't it?
SWPadnos_ is now known as SWPadnos
motors and encoders in the same cable would make me very nervous
yeah I know it's a calculated risk
(they're pretty low power)
they still have brushes, and they'll still be PWMed
there is a DB25 on the box, right? where do they go from there? both motor and encoder go to your interface board?
or is the DB25 part of the interface board?
motors and encoders both go to the interface/driver board
by discrete wires, ribbon cable, or is the DB25 soldered to the board?
wires to screws
in that case, I'd run the encoder wires thru ferrite beads, between the interface board and the connector
why no put a cord grip on the box and attach to the screw? then you only need the db25 on one end and a cable should be easy
so any crosstalk from motor leads to encoder leads in the cable will have to fight its way thru the beads to get to the interface board
your encoders are differential aren't they? that will help a lot - keep the pairs together as you go thru beads, and common mode noise will be attenuated quite a bit
just the spindle is differential
its a calculated risk, but at this point I'd be nervous
like you say, they're small motors, and maybe I overestimate the risk
but I'd be looking for separately shielded cables for either the encoders or the motors
sharing a connector is one thing, sharing 6 feet of cable jacket is another
centronics is definitely better. I'll look around and see what I can come up with. Maybe I could make a new board that fits in the green mounting thing
you can easily have 10's to maybe 100pF of stray C from conductor to conductor in a cable
if I use centronics, I think there will be predictable twisted pairs in the cable
I hate this kind of "last part" of projects like this
we have a saying at work: "labels and cables will get you every time"
product is ready to ship, except you don't have the label that says its UL approved, or the catalog number label, or some other silly piece of sticky paper
the "423" on one end ofa wire ... :)
Guest308 is now known as skunkworks_
skunkworks_ is now known as skunkworks
SWPadnos, how many times do you feel like thread crapping in geckodrive?
wrong chan again.
command (EMC_AXIS_HOME) cannot be executed until the machine is out of E-stop and turned on
I wish I knew why this happened intermittently
aha -- it seems to be correlated with starting homing just before exiting emc
SWPadnos_ is now known as SWPadnos
Guest164 is now known as skunkworks