PID Loop for stepper motors

Dear all,
I'm currently working on implementing a PID position control with LinuxCNC for a rotary axis. The set-up includes a stepper motor with a rotary encoder. I'm attaching the HAL configuration file, I'm not really sure if everything is set-up correctly or not. Can you please check it?
Thanks,

Amedeo

Ok done! Any other corrections?

Ok, I'm attaching the whole hal as well as the ini. Consider that the configuration is for a 5 axis robot, and only the first axis (axis 0) has the encoder configured. Hope it helps!

Ok so I've tried moving the axis by jogging it of 10 degrees in both directions. The axis start oscillating vigorously, until a following error. The settings used are:

P = 60
I = 0.01
D = 0
BIAS = 0
FF0 = 0
FF1 = 0.5
FF2 = 0.5
DEADBAND = 0.001
MAX_OUTPUT = 0

I then tried to lower the P value until the axis stopped oscillating, while setting I, FF1, FF2 to 0 (to simplify the configuration). A value of P = 10 did the trick. When I look at the axis.0.f-error in the HAL oscilloscope I get a sawtooth wave when moving (img_1.jpeg) and a train of recangular pulses when stopped (img_2.jpeg). Is it correct?
Also, if i jog of 10 degrees the final reached position is never exactly 10 but something like 10.080.
Hope this helps, thank you very much for your help!

I see you have FF1= 0.5 and FF2=0.5. At the same time you seem to run stepgen i position control mode. Then I don't think these combinations are the best.

When you run stepgen in position control mode you are better off with FF0=1 and FF1=FF2=0. There is no scaling when using stepgen so the commanded output position from motion should go directly to stepgen via the pid FF0 parameter set to 1.

Actually it is better to run stepgen in velocity mode even when using steppers. If you switch to velocity mode you should set the pid parameters to FF0=0, FF1=1, FF2=0.

When that is fixed, start with small P values until it oscillates and then back off. Well normal servo tuning methodology.

I should be running in velocity mode (?). I've set the stepgen for that specific axis to control-type = 1.
Ok I've found a value of P at which the axis doesn't oscillate. Do i have to change some other parameter?
Also a quick note: now the axis is moving really slow and it doesn't change speed even if I change the jog speed itself.
Thank you again for the quick response!

As Hakan mentioned tuning should be

FF0=0
FF1=1.000
FF2=0
P maximum stable value
D = 0
I = 0

Proper operation also depends on having commensurate stepscale and encoder scales