Re: Windows timing subroutines, how do they work?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mariss Freimanis"
<mariss92705@y...> wrote:

> In my opinion it should not be the task of a PC to do the 'donkey
> work' of generating step pulses be it Linux, DOS or Windows. That is
> a task that belongs to dumb dedicated hardware.
>
> A PC is an 'intelligence engine'. It's task is to do a lot of math
> and make decisions. Its output product should go to a 'pulse engine',
> hardware finely tuned to the task of generating of producing pure and
> clean frequencies on demand from the PC.
>
> These are tasks are so diametrically opposed it's like using a claw
> hammer for a screwdriver. In a pinch you can do it but it's not
> pretty.
>
> That also pretty much surmises what I have seen from most PC based
> CNC programs. The step pulse phase jitter is horrible even from the
> most popular out there. The motors sound like a barrel of agitated
> monkeys and I have the scope pixs to prove it.
>
> If things are going to be done right, the PC has to interface to some
> kind of step pulse engine.
>
> The 'agitated monkey' part. Motors that sound like that are being
> robbed of their potential torque especially at high speeds. Phase
> modulation imposes unnecessary torque demands (infinite impulse
> functions) on the motors. Said more simply, you pay for all that
> noise in performance.
>
> Mariss
>
>

The problem in the past and currently in the present, is that there is
no "standard" for an external pulse generator so you end up having to
buy a "system" that is composed of software and matching hardware.
Your options start to dwindle and if you want/need/desire to change
the software you have to throw away the entire system. It would be
like every car manufacturer deciding to use non-standard tires that
only they provided or each TV network broadcating in a different
format so you had to buy a set specifically for their signal format.
From a pure engineering standpoint it might make sense to hand off
signal processing to another circuit like a DSP card, but it needs to
have an open set of standards that ANY software company could write
to. If it's going to end up as a PC perhipheral then it needs to have
drivers or open standards that make it useful with different
programs. Show me a pulser card that is not single source, has open
standards and is supported by multiple vendors (especially MACH) and
I'll get in line to buy one.