[dondeaida]

Hello,

Mach is great but is limited to 45000Hz and I can't get decent speed at high microstep resolution as 51,200 Steps/Rev is common these days.

I hear Mach's 45000Hz limitation is imposed by parallel port, not by computer motherboard/CPU.

So I would naturally assume softwares that use USB port will have higher pulse rate.

Or even better pulse rate by using "dedicated PCI card".

Anyone heard of these types of software?
I would appreciate if you could inform me such softwares exist.

Thank you and have a great day.

[Torchhead]

Hello,

Mach is great but is limited to 45000Hz and I can't get decent speed at high microstep resolution as 51,200 Steps/Rev is common these days.

Wrong. Art just announced the latest version has 60KHZ and 100KHZ core freq selections

I hear Mach's 45000Hz limitation is imposed by parallel port, not by computer motherboard/CPU.

Nope. Art actually took it to over 200KHZ but the system video suffered.

So I would naturally assume softwares that use USB port will have higher pulse rate.

Depends. Other hardware shares the USB serial stream and stuffing 4 or 5 channels of 60KHZ Plus time sensitive I/O (encoders, etc) in there presents a bandwidth problem. You have to live with a 16ft length limitation with USB as well and it's not robust for long distances.

Or even better pulse rate by using "dedicated PCI card".

There are currently two major players in the USB pulse card: Flashcut and NcPod. Flashcut only works with their software controller. NcPOD is new and has a MACH3 interface.

Gecko has the G100. 400 bucks for an ethernet based pulse card and lots of I/O (with no isolation). It has higher pulse rates but code throughput is not that great.


[QUOTE}
Anyone heard of these types of software?
I would appreciate if you could inform me such softwares exist.

Thank you and have a great day.[/QUOTE]

It's hard to justify spending a lot of money for a pulse card when parallel ports are still around and cost less than $30.00. You can still get MoBo's with full communication risers including parallel and serial ports.

[Andre' B]

I think when most get the where they want such high resolution and high speeds they start to realize the benefits of servos with analog tach feedback velocity loops and hardware up/down counters between the position encoders and the computer.
Smooth, quiet, high speed high res. goodness.

[WayneHill]

Dondeaida,

What are you running that requires such a high Step/Rev resolution?


Wayne

[samco]

emc2 has a few options
http://www.linuxcnc.org/

pico systems with emc will do 300K (printer port controller)
http://jelinux.pico-systems.com/univstep.html

There are a few things in developent...
there is a fpga card that is now used as a servo interface card (pci fpga) that is being updated to support multible configureations including steppers. http://www.mesanet.com/

A little known guy (pluto fpga parallel port card) That has servo support now but the developer is working on a step generator.
http://emergent.unpy.net/01166412010 <- servo
http://axis.unpy.net/index.cgi/01183862490 <-stepper

I have been playing with the pluto as a servo controller and it has been working great.

There is no usb style step generators for emc yet.

[dondeaida]

I am reading your previous posts and you really know your stuff. Thank you again.

[keebler303]

I am not aware of any application which requires .007 degree accuracy and high speeds. You are asking for commercial performance from a hobby based market. If you want high pulse rates, check out galil. They will read encoders at 22MHz, and the price is not too bad. But you also need custom software to talk to the galil card, that is why there is a big difference between Mach3, which is amazing for what it is, and (say) a fanuc controller with a $20K+ price tag. If you actually NEED this resolution and speed, you have to be willing to pay for it. No matter how many tweaks you do to your pinto, it is just not going to perform like a mustang.

Matt

[ger21]

A new usb pulse generator for Mach3 begins beta testing next week, with a pulse rate of 4 Mhz, and and expected price of just over $150. It's called the Smooth Stepper.

Also, Mach3 can run PCI Galil cards now as well.

[glamoursfx1]

Will Mach3 not run the older ISA cards...I have a DMC1730 which i have had kicking around for about 6 years, and was hoping there would be a breakthrough...so it could be used..I remember there was some software to run it, but it was a lot more expensive than Mach or Master 5 at the time..

Thanks Dave

[keebler303]

Mach won't run the older ISA cards. I have written some software to talk to a DMC-1000 card but it is a specialized use, not for G code, etc.

Matt

[glamoursfx1]

what about controlling a PCi 2700 card from a shopsabre setup.