Parallel port to USB for TinyG

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Christine88
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Joined: Tue Oct 07, 2014 4:16 pm

Parallel port to USB for TinyG

Post by Christine88 » Thu Oct 30, 2014 11:03 pm

Hello all

So I have a Shapeoko 2 with a TinyG board which has USB port to connect to PC. As everyone here knows Mach 3 has no USB option but only parallel port. So would it be possible to use a parallel to USB cable adapter to run Mach 3 with TinyG?

cvoinescu
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Re: Parallel port to USB for TinyG

Post by cvoinescu » Fri Oct 31, 2014 12:09 am

No.

TinyG takes G-code on the USB-to-serial input and generates step and direction signals for the motor drivers.

Mach3 reads G-code from disk and generates step and direction signals for the motor drivers on the parallel port.

Both want to do the same thing, so they can't work together.

The only way for them to work together would be to disable the processor on the TinyG board and route the signals generated by Mach3 directly to the motor drivers on the TinyG board, but that would be difficult, and a waste of a good controller. Just get four Pololu drivers and wire them to the parallel port, and save the TinyG for something else. Or buy a three- or four-axis driver board, those usually plug straight into the parallel port and work with Mach3 out of the box.

And, actually, Mach3 has USB support. It can connect to a board such as the SmoothStepper, via USB or Ethernet. It still does the G-code interpretation, the motion planning and all the timing calculations, but it delegates the actual generation of step pulses and direction signals to the microcontroller. But you can't use TinyG for this (unless someone ports the SmoothStepper firmware to the AtXMega processor of the TinyG, which seems unlikely).
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

Christine88
Posts: 168
Joined: Tue Oct 07, 2014 4:16 pm

Re: Parallel port to USB for TinyG

Post by Christine88 » Fri Oct 31, 2014 12:44 am

cvoinescu wrote:No.

TinyG takes G-code on the USB-to-serial input and generates step and direction signals for the motor drivers.

Mach3 reads G-code from disk and generates step and direction signals for the motor drivers on the parallel port.

Both want to do the same thing, so they can't work together.

The only way for them to work together would be to disable the processor on the TinyG board and route the signals generated by Mach3 directly to the motor drivers on the TinyG board, but that would be difficult, and a waste of a good controller. Just get four Pololu drivers and wire them to the parallel port, and save the TinyG for something else. Or buy a three- or four-axis driver board, those usually plug straight into the parallel port and work with Mach3 out of the box.

And, actually, Mach3 has USB support. It can connect to a board such as the SmoothStepper, via USB or Ethernet. It still does the G-code interpretation, the motion planning and all the timing calculations, but it delegates the actual generation of step pulses and direction signals to the microcontroller. But you can't use TinyG for this (unless someone ports the SmoothStepper firmware to the AtXMega processor of the TinyG, which seems unlikely).
What would be a good four axis driver board?

cvoinescu
Posts: 4442
Joined: Thu Jul 19, 2012 6:50 pm
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Re: Parallel port to USB for TinyG

Post by cvoinescu » Fri Oct 31, 2014 2:03 am

Ask Improbable Construct, he has a TB6560-based board from China that he's happy with. (They're a bit of a crapshoot, unfortunately.)
Proud owner of ShapeOko #709, eShapeOko #0, and of store.amberspyglass.co.uk

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