[draughted]

the gecko setup
in emc configuration generally has a
step time :4000
step space :500
Direction hold :20000
direction setup : 1000

just a question of if its the same for the g540 and its smaller drives.

[draughted]

the only reason i ask is i have been having some missed steps
and EMC suggests checking the step driver settings.

if anyone knows its correct i'd be happy to hear it.


on other thing i'm hung up on, is the explanation emc gives in the 'setting up your base period' section of the manual. where it confuses the hell out of me with a long winded example of lowering the base period for gecko drives.

does any one understand how your suppost to change the 'dir hold' to 2 when it is already 20,000.

i can open the ini file an all but it is confusing.

[acondit]

Did you setup with stepconf or manually?

Alan

[chester88]

The section your talking about was taken from this wiki writeup:
http://wiki.linuxcnc.org/cgi-bin/emc...StepGeneration
I'm not sure if the stepgen was changed from using multiples of base period to using time in nanoseconds or the original text was wrong, bu the man page says that stepgen requires time in nanosecond.
In a terminal type 'man stepgen' to read that.

[draughted]

i set up with stepconfig and have seen the inside of ini. it run fine but i've got 32,000 base period and would like to maximize my speed , read geckos can go faster than base.

[draughted]

re-reading the write-up i can't for the life of me work out were he gets those numbers and the fact that to gecko drivers 202 and 203 have different frequencies leads me to believe i have been using the wrong driver settings.

i've heard(and read on gecko site ) the g540 and its 250's are little 201's
,does that reffer to the frequencies used, i suppose.

[chester88]

The manual for the 250 says the step time is 1000 ns minimum. It doesn't says anything about the rest. Maybe you could ask on another cnczone thread. Gecko is represented here somewhere... Either that or just try some different settings and see what works.

[draughted]

yeah, after revisiting the gecko site i read it has the features of both 201 and 202
so i'm confident in using the gecko pre-set in the stepconfig

[samco]

This is a .stepconf that you can open in the step config wizard. It was setup by one of the emc developers. He would like some feedback.

http://www.linuxcnc.org/wiki/uploads/G540.stepconf

sam

[chester88]

If you look at that config (just given) then timing is 1000 for steplength, stepspace, dirhold, and dirsetup. That sounds like a good place to start. The timing is not the same as the 201 or 202 . Further more your first post says you used steplendth as 4000 and step space as 500 - according to the EMC wiki that should be the other way around (but that is for the 201, 202, 210 or 212 anyways)

[draughted]

ok, i don't have my machine with me,but when i get home i'll look into that.
if thats the case the g540 is a much better driver than i thought and it explains my unfortunate first few attempts. i first started in the deep end trying to route out a foam shell that ended up being right out of square. hense this thread with me trying to find out whats wrong.

the figures i gave earlier were straight out of my version of EMC stepconfig.if they don't match the 201 then go figure.

any way i'll be glad to see my new ballscrew design can pull higher speed.

[chester88]

What version of EMC are you using? It must be a bit old. Yes some of the step timing numbers were backwards at one time.

[draughted]

i do believe it is v2.3
but just recently i changed the step time to 4500 from 4000
and the speed went through the roof

[chester88]

So what is all the timings setings you now use?

[draughted]

well yeah i've been using the standard set by EMC
but have only changed the step time to suit the g201
i was not getting a very accurate cut (many missed steps)
so i'll have to do a few tests to see if its better or not


do you know of any links to a good gcode that can be used to calibrate

other than that i have to learn to write gcode

[draughted]

just an update chester was correct i did have an out of date version and have updated to 2.3 but now need to re-fix my SMI issues and get machining again

the timings fot the g540 are easily selected in this new version.

thankyou for your help

[Fredworrell]

The manual for the G540 shows the following.

Step pulse "0" time = min 2 uS
Step pulse "1" time = min 1 uS
Direction setup before step rising edge = min 200 nS
Direction setup hold after pulse rising edge = min 200 nS

[chester88]

we now recommend:
1500 step
2500 space
dir 700
hold 700

A bit more conservative but still allows more speed then most can use.


Chris M

[Fredworrell]

Thanks for the info. The only reason I posted them here was because no one ever said what the final settings were. Great info. I'm sure others will appreciate this as well.