7i95T & 7i77

Yes i meant the RPI required part.
I got fed up with RPI, first when i bought 3 and found out they are utterly underpowered and require huge amounts of time to get anything working on them (this was back in the RPI3B era), and got disgusted by youtubers shoveling them as the only option to run Klipper/3D printers during the pandemic when the price got to over 180$ !!! Second hand laptops are much cheaper and much more powerful, and can easily run Klipper.

Thanks a lot! 
if I understand correctly, you mean the FW is fine for using either step/dir on 7i95T or Analog on the 7i77? All I need to change is in ini, if I at some point have to/want to change motors?

i made it a step further. sadly the mesact tool also knows nothing about that card match, I used the 7i97T in the tool to get a basic Hal/INI and search/changed 7i95 to 7i95T. wich also wanted to startup. I kind of hacked something together. Now the machine starts at least, I see pins in halshow. so a win I guess?!
The conig is quite minimalistic. I just added the Axis xyz. the idea was to start with the basics and just go step by step - adding outputs and inputs later on, to minimize error.

my idea was to just have axis, jog them, watch for +10/-10v output in halshow.

sadly I already ran into another issue I don't quite understand. hope it is fine to ask another question in this thread. 

The issue: I can "power" the machine and as I try to jog an axis I get "follow error". I don't see any feedback/encoders configured. why?!
Also I don't see any voltage output on the analog ports. maybe there is something wrong with my ini/hal or I am looking in the wrong place in halshow. I don't really know...

I share my Hal and ini if someone wants to take a look

As I mentioned, if you want a 7I77 analog configuration, create a 7I92+7I77 configuration
(with either pncconf or MesaCT) and when done, change the boardname in the ini file from
7i92 to 7I95.

Note that following errors are expected until you get the encode scale correctly, in the proper direction,
proper feedback direction, and tuned. This is why you typically set the following error limits quite wide
in initial testing. After the basics are set up you will need to follow on of the tuning guides.



 

thanks!

7i72: oh shi.... sorry... I missed that somehow.
tried mesact with it, sadly does not put out any working stuff.
pncconf did!
machine is starting and I can jog until following error again.

in general:
if I don't want to wire encoders to the mesa, I have no feedback. so far I understand. But is that a bad thing? It would be like running with steppers open loop, isn't it?
I thought it should work, as it obviously did successfully with the old (now dead) controller before for years (so far I looked up all signals that came from the old controller was analog voltage, all feedback is in servo controllers)
if I connect back the error signal from the servo drives I should be able to estop if thinks go out of control. just like I know from another project with stepper drives. that at least was my thought to remove complexity , since I am completely new to servos.
is that a completely bad idea in your opinion?

In Office I can't test with motors because they are 400v... also the machine is a few km away and I am trying to prepare it, until I can come back to it.
I just wanted to test whether or not I get +-10v on the ports to make sure it's virtually wired correctly. Also I want to try if I can cancel movement with e-stop. is at least have to find a way to ignore feedback for now, to have room to elaborate my config. it would be kind of sad to drive there just to see I missed something essential to test-drive or tune.

i also found the 7i77 servo tune post, wich I am currently reading to get used to what I need to do in future.

any workflows / hints appreciated.
as I said, I am a beginner and just trying to figure out things, bumping into new stuff on the way

Thanks for your patience and answers

BloodyT wrote:

i also found the 7i77 servo tune post, wich I am currently reading to get used to what I need to do in future.

Is it this one?
forum.linuxcnc.org/10-advanced-configura...ning-detailed-how-to
No skipping steps there!!!
And you can not ignore feedback on analog servo systems if the motors are mounted on the machine, that ends up badly. But for testing on the table/desk you can, although there is no benefit to it, feedback must be sorted before even enabling the drives.

yep! I try thanks