RE: [CAD_CAM_EDM_DRO] Re: parallel port finally obsolete?

USB is a network, so unlike the parallel or serial port there is a lot of
'stuff' between the PC and what it's talking to. That 'stuff' leads to
delays while everything chatters back & forth sending your data, plus you
are sharing the line with other devices. With parallel, it just the PC and
the device, the CNC driver in this case.

For the OP plugging a parallel card into the machine might be the easiest
option. Check the BIOS to see if there are any settings for the parallel
port, in that case you just need the little cable that plugs into the
motherboard, like this:
http://www.amazon.com/DB25-Motherboard-Parallel-Connector-cable/dp/B003V70P1
I. Most hardware shops or techs will have a box full, they'll cheerfully
give you one or six if you ask nicely.

Otherwise you need something like the SmoothStepper, that controls the CNC
while the PC merely feeds it data.

Tony

> The best answer I can think of is this: Usb is serial information, which

means

> you have to use some devise, like a uart to build strings of info and time

share

> it for translation of code. The parrallel port transmits info with more

bits at a

> time,in bigger chunks of info. serial is slower due to the reconstitution

of data,

> and the time it takes to accomplish that task. Parallel to usb conversions

use a

> surface mount uart(very small)to convert the parallel data to a serial

string of

> information usable by the cnc device you may plan to use...I have a usb
> interface on my new cnc kit I designed to use an arduino controller with 3
> 20amp 24vdc stepper motors for my new plasma cutting/welding table. (it's
> also wireless@2.4 ghz),and can be loaded with a sdram card for independant
> operation...(I am working on nesting software,so If you could help,I would
> appreciate it...)...artinvegas...
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "scyvt" <scy@...> wrote:
> >
> > Forgive me if this topic has been already thoroughly covered - I did a

search

> and didn't find the answer I was looking for, but I may have given up too
> quickly.
> >
> > Being a Macintosh person, I didn't have older PC's with parallel ports

around,

> and wasn't comfortable evaluating used machines. Just recently an unused

2-3

> year old Lenovo desktop came into my hands, but of course it has only USB
> ports.
> >
> > Has the longstanding need for parallel ports now been abolished? If so,

what

> hardware is now available to interface between USB and stepper drivers? Is
> there a choice, and if so, pros & cons of each?
> >
> > TIA
> >
> > Steve