I have been testing the PoKeys 56E's encoder inputs with the new plugin that Brian is at this time developing.
I have been very impressed so far
I have one of the encoder inputs connected to the buffered encoder outputs on a servo drive which has a 4000rpm motor with 2000line (8000ppr) encoder. At full speed that equates to 533KHz. I have not lost a single count even when running the motor at full speed over a period of hours with frequent  reversals at 1000 revs/s/s acceleration set.

This opens great possibilities to me, it means I can basically have encoder feedback to Mach which could be monitored for position errors if wanted but what I really am looking forward to is being able to reference the machine once when I start Mach, it could actually just be done once and never again unless 56U and encoder are powered down but I will personally home on each start of Mach. This means if I E-Stop or Disable/Enable drives I could have a message pop up to ask if I want to update Machs machine coords to the encoder position if it is different. This is great for me as all axis will lose position to some point when an E-Stop situation has occurred or drives are disabled. Even steppers will lose position if they are disabled as they will jump to the nearest full step. With encoder feedback Mach would know and allow you to update if you choose.

Another possibility is to have encoder index homing which will be very accurate. Currently I do this external to Mach in my servo drives but being able to do it inside of Mach means that servo drives without this capability or even steppers could be homed to an index pulse as long as you have an encoder fitted.

So in short as long as the standby power to my servo drives logic and the power to the pokeys is kept alive the actual axis position will always be known by mach when it starts and can be updated if required

Hood

Hello Hood,

I'm also trying to test new plugin with my Pokeys56U and I have some truble. I don't know how to map digital inputs to a userLEDs.  Have you tried that already?

Peter

Should be able to use the config option once the plugin progresses a bit but for now I think you would need to use VB in the macropump.
Hood

Thanks Hood. I know that at this moment inputs and outputs are only available from VB. I'm trying to figure out from manual how it's done, but it is too much complicated for me. I'm not very good at VB 

Peter

Neither am I
Took me a while to work out what to do and would take me just as long to do it again as its been a while since I originally messed with it. I am not in a real panic for using it so I will wait for the dummies point and click version
Hood

Hi Hood,

Got a question for you. How would you go about doing homing using a servo's index pulse? I imagine that after Mach finishes its regular homing routine and bounces off the switch I will have to use a macro that will rotate the motor in a set direction till it detects the index (not sure how to do that either). But will a macro be able to see a pulse as short as a servo's index? I am going to use an ESS which will see the pulse no problem, but I am concerned how a macro will see it?

Dan

I dont think you will manage that Dan, it would need to be a function of the ESS plugin to be any good. My Servo drives do the homing internally and all I am doing is telling Mach it has homed. Likewise for the PoKeys, it would need to be in the plugin for it to be fast enough and repeatable I would imagine. I would think even homing to switches is done in the parallel port driver as even that would not be good enough at the update rate of Mach itself.
There used to be a breakout board that did Index homing but unfortunately they are no longer made, I have one on the lathe although I dont use that function of it now but when I did it worked well.

Hood

Thanks Hood. Looks like I misinterpret the sentence about index homing in your first message. You said you were doing homing external to Mach, so I concluded that you implied that Pokeys would allow you to do it internally in some way.

Dan

Not gone back and read what I said but at the moment I do the homing in my drives, I was in hopes that the Pokeys plugin would at some point support index homing. The SS/ESS is also supposed to be supporting this at some point I think but when any of that will happen, if indeed it ever does, I have no idea.
Hood

Ah I just read and see I should have worded it a bit better, when I said within Mach I was meaning in the plugin.
Hood