I suspect that the inverted board on the right could be pulled off, and step/dir pulses fed into the headers.
Sounds like a plan!
just some tracing. What would the controls of a stepper driver be?
if you could read the number on those driver chips, we could be sure
often just enable, step, direction
So it's the end of our hour, and we need to let Andy get back to work, or the shop as the case may be. Feel free to stay on and keep chatting, this has been hugely informative. I want to thank Andy for his time today, and everyone else for coming along for the ride.
Looking at the data sheets of the driver chips and tracing tracks would probably allow you to keep the existing drivers. Which are probably rubbish. But that approach leaves you the option of plugging the old board back in to return the machine to a working state during the refit. And that can be very nice.
Thank you Andy!
Thank you Andy and Bari!
@Andy Pugh Thank you, and congrats on having your random retrofit in a chat, with no prep turn out... looks like it will anyway. :)
I can actually stay a while longer, all you are keeping me from is wrestling with the generation of LinuxCNC documents in a language I can't even read.
So, I noticed from the 3D printing world there is a whole evolution of stepper motor drivers. What has changed in the last, oh, 20 years?
Where would be a good starting point on reading up on Linux CNC
Fine by me - I'll wait a bit to pull the transcript, so we don't miss anything
Does linuxCNC has repository for android?
Yes, L6208 are step/direction drivers, and they are pretty decent at 52v/5.6A max.
They still convert pulses to 2 waveforms, no?
But let me just plug next week's Hack Chat: Back to Basics with "Simplifier":
Mainly everything now is bipolar, so you get twice the torque from a motor. And clever pulse shaping to deal with resonance, induction etc.
Keep it simple, Simplifier Wednesday, July 15, 2020 12:00 pm PDT Local time zone: Hack Chat This event was created on 06/19/2020 and last updated 2 days ago. Join this event's team Simplifier will host the Hack Chat on Wednesday, July 15, 2020 at noon Pacific Time. Time zones got you down?
Read this on Hackaday
Using circuits from old smartphones to run CNC m/c.
Ah, and the drivers can now also detect 'missed steps' due to the power response of the motor , stuff like that?
Might be worthwhile to fully retrofit this baby. Give it some TLC.
@Dipjyoti Kumar Smartphone are about the worst real time controllers I can think of. Full of blobs that you'll never be able to access and turn off to get in the way of real time. But possible useful for a GUI.
@Axel Yes, and from that detection you have the ability to correct and/or fail and/or dynamically increase the current you are providing during moves that need it.
I think that they might be able to, but I don't know any that do.
The hot new thing now is closed-loop steppers, where there is an encoder on the motor. That basically makes a stepper into a real brushless servo motor, just a wierd 2-phase one with an lot of poles.
(and be quiet for the rest)
That's one thing LCNC lets you do is dual closed loop. Closed loop to the stepper/servo, and Then linear scales too.
@Axel if you are using just open loop step / dir drivers, then no.
but for example on my milling machine I'm using the...
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