China Mach3 Motion Controller

Hi,
yesterday i bought a china 6090 Router. It has a Mach3 Motion Controller, i was aware that LinuxCNC is unable to use USB so i allready ordered a BOB.

But, i am still curios and dont understand how it is possible that mach3 is using windows and usb and the setup works. I understand that they use a Buffer on the usb device but i do not get behind how the input is connected to timing. Do they drop timestamps toghether with the data on the controller? In theory linuxcnc should be able to have a hal for that buffered usb only because it works on windows
Greets

The reason why LCNC achieves it performance is that the OS runs in real time and Windows can't. Some of the smooth stepper boards are their own buffered motion controllers but LCNC is the motion controller. Ethernet Smooth steppers run at up to 2 or 3 Mhz max ( I can't remember exactly). The closest equivalent ethernet board for LCNC (Mesa 7i76e) runs at up to 10 Mhz. And has 5 stepgens, 2 MPG inputs, a spindle control, 32 inputs and 16 outputs. There is a reason why a number of commercial businesses have moved from Mach to LCNC.

Good luck with your journey.

LinuxCNC's basic architecture has most or all of the real time operations done by the host computer

This has advantages and disadvantages:

Advantages:

Single locus of control, no buffering of motion so real time motion features like adaptive feed, probing and rigid tapping are controlled by the host and simpler and faster than with buffered systems. An example of this advantage is LinuxCNCs almost instant response to feed hold compared to buffered controller based systems.

Complex motion control parts are open source, extensible, and running on a fast CPU with basically
unlimited memory (rather that being moved to a separate motion device which may not support all motion features,
is likely closed source, has limited resources and is not extensible)

Because all of the complex motion options are done in real time on the host CPU, all LinuxCNC systems, from ones using simple parallel port interface to complex Ethercat systems have the same motion options including threading, rigid tapping, probing etc. With separate buffered controls these options depend on the remote device so you may only get a subset of capabilities or buggy ones.


Disadvantages

The main disadvantage is that LinuxCNC requires a real time OS so you cannot run on Windows for example.


As a side note, people have run LinuxCNC with external USB motion devices (buffered and unbuffered)
but none of these are mainstream

And yes, buffered motion systems typically use what I would call a PVT (Position, Velocity, Time) system
where motion packets contain position waypoints, plus velocity and timestamp information (the timestamp may be
an assumed value per packet so not actually present)