USB and Ethernet Mach3 motion controller PLCM-E3

[John S]

I'm reading it as it has Ethernet, USB and DB25 as inputs and outputs go out the 9 pin serial direct to the stepper drives ?
If so and it can use USB or Ethernet why a BoB ?

Documentation isn't very clear.

[Jonathan]

Documentation isn't very clear.

Indeed...

Although this bit implies its output is the same pinout as the parallel port:

The branded software enables one to use the I/O ports of the
controller in MACH3 instead of computer built-in LPT ports. If you
were earlier using a computer LPT port to connect drivers, you will
need to disconnect the connector from the computer LPT port, connect
it to the PLCM controller and install the appropriate plug-in
for MACH3.
Each controller has at least one port completely matching the
physical LPT port.

If so that sounds like a good idea if you've already make your control box. Just plug this in between and go.

Still not liking mainly the lack of information about the interface/software/drivers but also the 100KHz limitation and only being compatible with Mach3.

[John S]

If so that sounds like a good idea if you've already make your control box. Just plug this in between and go.

Still not liking mainly the lack of information about the interface/software/drivers but also the 100KHz limitation and only being compatible with Mach3.

So if you have already built your box and you plug this in between what do you achieve except a hole in the wallet ?

It worked before you plug it in so why ?

100KHz isn't any worry for me as I still use the base frequency of 25Kh, plenty fast enough at my age dick slapping is no longer an art form.
Again Mach suits me, it works and you don't have to be a geek to use it.

[Jonathan]

So if you have already built your box and you plug this in between what do you achieve except a hole in the wallet ?

Yeah I wasn't suggesting anyone should buy it!

100KHz isn't any worry for me as I still use the base frequency of 25Kh, plenty fast enough at my age dick slapping is no longer an art form.
Again Mach suits me, it works and you don't have to be a geek to use it.

I only use 30KHz. In the vast majority of cases >100KHz is pointless. It's only useful to achieve high resolution with servos, so if you don't use servos you are basically paying for the convenience of a USB cable, which does seem rather silly.

I think having and operating CNC machines already qualifies us as geeks so it's a bit late for that. I had a couple of unresolvable problems with Mach3 last week, so I promptly switched to LinuxCNC. No regrets.

[Purelogic R&D]

It says " Controller can be connected to any BOB or CNC driver box (destined for LPT-port) via DB-25 connector."
If you are using the parallel port they why the ethernet and USB connections ?

Pls do not confuse connector with port. PLCM-E3 have 3 output ports, pinouts are similar to LPT, but it doesn't mean that they are the same.

So if you have already built your box and you plug this in between what do you achieve except a hole in the wallet ?

Stability, speed and torque.
Of course, if you absolutely satisfied with how do your CNC system works, you don't need PLCM.
But in most cases, due to PC motherboards' hardware issues, MS Windows and Mach3 architechture, output freq. on pins of PC's LPT-port is very unstable.
Who have such possibility - just use your oscilloscope to check this.
So, this causes a) step missing b) limiting maximum of speed and torque.
You can check this video: www.youtube.com/watch?v=3Gi2B2qUJ_k
This test shows that no-load max. rotating speed higher up to 40% with PLCM.
Also, there are one issue in mach3 with late changing DIR signal.
Also, i think most of Mach3 users know, how sensitive it is to Windows interrupts. Suddenly started screen-saver can make the part you're processing now into the garbage.
You can also check first question in our FAQ.

[John S]

Sorry still doesn't explain what it does.
Simple question? Can you connect to a computer via USB or ethernet and run the stepper drivers off your board. I.E. like the smooth stepper

[Purelogic R&D]

Simple question? Can you connect to a computer via USB or ethernet and run the stepper drivers off your board. I.E. like the smooth stepper

Yes.
but, also like a smoothstepper, it's still need a bob.

[Purelogic R&D]

Sorry still doesn't explain what it does.

Mach3 motion controllers all have similar principles which are due to Mach3 architechture.
It does:
1) receive and buffers trajectory info from Mach3 by USB or Ethernet.
2) Process this info, transforming it to STEP/DIR/ENABLE pulses, generate them on it's "out" pins
3) receive and process signals from "in" pins
You just connect your BOB or multichannel driver to PLCM(using DB25 cable), PLCM to PC.
So, using motion controllers you decrease load on PC's CPU, system become insensitive to Windows interrupts, you get stable impulses on pins(motors rotates more smoothly) and so on.

[John S]

OK got it now, my bad I was getting confused with a picture I had seen of your breakout board and thought the PLCM-E3 had plugs on for the stepper drivers.

Looking at the PLC4X BoB, do you have a manual in English ?
Also you have PP port on one end and 9 pin serials on other side.

Why not fit screw connectors to the board instead of 9 pin serials, seems messy having to use the extra connector boards just to get cables out ?

[Purelogic R&D]

Looking at the PLC4X BoB, do you have a manual in English ?

No. PLC4x will be reworked and upgraded soon.