[Etherlab-users] Configuring EL7047 stepper driver

Fontana Nicola ntd at entidi.it
Sat Jul 24 15:01:31 CEST 2021

Hi all,

I think this issue is not related to the ethercat software per-se but
maybe someone has already met something similar or can point me into the
right direction.

I'm trying to configure the EL7047 stepper driver in position controller
mode without encoder (by default it is in velocity mode):


No matter what: it stays in PREOP state after having configured it.
Whenever I try to put it in SAFEOP/OP I get:

    Failed to set SAFEOP state, slave refused state change (PREOP + ERROR).
    AL status message 0x001E: "Invalid input configuration".

Here is the full script I'm using:


It runs successfully and I am sure the settings are changed (I checked
them many times). For a couple of parameters, with a datatype smaller
than a byte but bigger than boolean, I had to explicitely set the
datatype to `uint8`, and AFAIK this is the only thing that "stinks".

The Beckhoff manual keeps reporting TwinCAT screenshots instead of
explaining how things work but (1) I do not have access to TwinCAT
and (2) I have less than zero interest in depending on a software blob.

Not sure it is relevant, but here is the output of `ethercat sl`:

    0  0:0  PREOP  +  EK1100 EtherCAT-Koppler (2A E-Bus)
    1  0:1  PREOP  +  EL1809 16K. Dig. Eingang 24V, 3ms
    2  0:2  PREOP  +  EL1809 16K. Dig. Eingang 24V, 3ms
    3  0:3  PREOP  +  EL1809 16K. Dig. Eingang 24V, 3ms
    4  0:4  PREOP  +  EL2809 16K. Dig. Ausgang 24V, 0.5A
    5  0:5  PREOP  +  EL2808 8Ch. Dig. Output 24V, 0.5A
    6  0:6  PREOP  +  EL7047 1K. Schrittmotor-Endstufe (50V, 5A)


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