LinuxCNC + Orange Pi (allwincnc)

Hi Tjtr33 and Dolence
I don't know why we need to use STEPGEN function?
Since AllwinCNC not using the base thread for the step generation.

It uses the servo thread to send position info to the ARISC to generate steps. The config file still needs the config values for the Stepgen

STEPGEN_MAXVEL =
STEPGEN_MAXACCEL =

Hi envyvan
IGNORE THIS UNTILL ... i dunno and i cant tell when


We dont need stepgen function
We use the arisc pwm module
which has a similar purpose as the linuxcnc stepgen

sorry if i used old words for new modules.
I still make all my folders prefixed with emc

Since i cannot yet build the arisc code,
I dont know much of the internals.

tomp

Hi Bari,
Thanks for your reply
Hmmm, That's weird.
I use the config file come from the example 3T and 3A.
There is no STEPGEN inside the example and still made the stepper motor work.
and also inside the hal file, no any STEPGEN connect to the servo-thread

# load RT components
loadrt [KINS]KINEMATICS
loadrt [EMCMOT]EMCMOT base_period_nsec=[EMCMOT]BASE_PERIOD servo_period_nsec=[EMCMOT]SERVO_PERIOD num_joints=[KINS]JOINTS
loadrt arisc pwm="p,p,p,f" out="PA12,PA11,PA1,PA10,PA9,PA13,PA14,PA0,PA3,PC4" in="PG6,PG7,PG8,PG9" encoders=1
# add RT functions to the servo thread
addf arisc.gpio.read servo-thread
addf arisc.pwm.read servo-thread
addf motion-command-handler servo-thread
addf motion-controller servo-thread
addf arisc.gpio.write servo-thread
addf arisc.pwm.write servo-thread

I did like to set it up to replace my mach3 system, Runing old xp computer cause some problem for me.

hi Bari
the supplied configs do not have those terms
( STEPGEN_MAXVEL STEPGEN_MAXACCEL )
and they run
maybe there some default value coming into play?

@MXMaster can you talk about this a bit so users know what's needed?

@MXMaster is port G numbered 6? can it's pins be used for pwm stepgen?

thx
tomp

tomp

Sorry I have now lost track of the config changes for this. He has had the project on three different sites and repos. I'm going to stay out of it until I have time to build a proper u-boot and get a optimized RT kernel config.

envyvan wrote:

MAX_VELOCITY = 150.0
MAX_ACCELERATION = 750.0
SCALE = 256.0
I think this value is quite fast for a hobby cnc.
If I don't get it wrong, SCALE should be how many pulse for 1mm or inch, then you set up the VELOCITY to 150mm per second.

I not sure the H3 CPU would able to handle it.
And I also notice AXIS GUI seems like to show up quite much warning and error which tklinuxcnc GUI does not.

Oh, it depends on your hobby! It's a very large machine with thick screws and this is why I'm using a higher number of steps division to achieve better accuracy or else it would be only 8 steps per mm.
If I'm not wrong it's a simple math since I have a 200 steps per revolution easy servo, my driver set to 32 microsteps and a screw pitch of 25mm without any gears or pulleys. 1mm/25mm = 0,04.

200 x 32 x 0,not04 = 256 steps per mm

It's around 46Khz which should be doable since it's done in the ARISC coprocessor and not the CPU itself, right? Apart oh this, I'm having the same error even with stock configuration (3A_TEST example).

To tjtr33

This is editor is really annoying. It's hard to answear without having the format destructed.

>>> did you fix ( nail down ) the cpu speed?
>>>You can use Armbian-config to set the min and max to the same value
>>>and choose the governor as performance
Yes I did it!

>>> the arisc_pwm_stepgen is not the same animal as linuxcnc stepgen
>>> the arisc criiter doesnt have the same params, so dont add flippers onto a cat.
>>> dont add stepgen_max_accel etc to arisc stepgen
>>> some ferrors could be due to a varying cpu speed, see above
>>> did you follow the urls send by Bari concerning following errors?
Yes I did follow it. I toughted MIN_FERROR or FERROR are too small for the setup, which now I believe is not because even unreal high values give me the same error. Any other toughts on this?

>>> hey! there is no stepgen_maxvel in an arisc pwm_stepgen
>>> if you are using standard linuxcnc stepgen on an opi
>>> the you will have very low steprates, low acc, and no experience from me
>>> ditto for stepgen_maxaccel >>> please use linuxcnc stepgen OR arisc pwm_stepgen NO MIXING
Yes, I agree with you on this. But it didn't come from nowhere. I read somewhere that for higher speeds you have to set it 20% higher to create a headroom for corrections or something like that. I still waiting for a consensus on this one.

>>>summary
>>> read the ferror docs
I could be missing something on here.

>>> please fix (nail down) the cpu freq
Already did it.

>>> please adapt a supplied config.ini, dont add items that did not exist in original
It was one of the first thing I have tried. Adaptation was an attempt to solve the issues.

>>> try 1 thing at a time, and post your results
OK, god bless you for being this patient! Wish me luck!

Bari wrote:

Sorry I have now lost track of the config changes for this. He has had the project on three different sites and repos. I'm going to stay out of it until I have time to build a proper u-boot and get a optimized RT kernel config.

He may be busy with this or something else might be hapenning. It may be a serious bug on latest version. I've tried to reach him via email without any response and made a post on the russian board too. The only thing I can do is wait for the other guys testing latest version too.