How to use Step Stick Steppers in MPF¶
Related Config File Sections |
---|
hardware: |
step_stick_stepper_settings: |
digital_outputs: |
switches: |
steppers: |
MPF can drive steppers on a StepStick (or DRV8825) connected via a digital output. Depending on the jitter of the output the speed might be limited to a few steps per second (like 50-200).
TODO: Add a picture of a step stick or DRV8825
Configuring your stepper¶
A step stick stepper needs two or three outputs which define the hardware
number: direction_output:step_output
or
direction_output:step_output:enable_output
.
In addition, you need a homing_switch
so MPF can find the 0
position
of your stepper at startup.
This is an example:
#config_version=5
hardware:
stepper_controllers: step_stick
digital_outputs:
c_direction:
number: 1
type: driver
c_step:
number: 2
type: driver
c_enable:
number: 3
type: driver
switches:
s_home:
number: 1
steppers:
stepper1:
number: c_direction:c_step:c_enable # enable is optional
homing_mode: switch
homing_switch: s_home
named_positions:
10: test_00
20: test_01
50: test_10
platform_settings: # optional speed settings
low_time: 20ms
high_time: 20ms
#config_version=5
hardware:
stepper_controllers: step_stick
digital_outputs:
c_direction:
number: 1
type: driver
c_step:
number: 2
type: driver
c_enable:
number: 3
type: driver
switches:
s_home:
number: 1
steppers:
stepper1:
number: c_direction:c_step:c_enable # enable is optional
homing_mode: switch
homing_switch: s_home
named_positions:
10: test_00
20: test_01
50: test_10
platform_settings: # optional speed settings
low_time: 20ms
high_time: 20ms
You might want to change the speed in the
platform_settings
section.
1000 / (low_time + high_time)
will be your number of steps per second.
Connecting your stepper driver¶
Connect the DIR
pin to your direction_output
, STP
to your
step_output
and GND
to your ground.
If use an enable_output
connect it to EN
.
Otherwise, pull it to GND
or the driver will not work.
Connect SLP
and RST
to VDD
(not all driver have all of them).
In addition, you need to pull M0
, M1
and M2
to VDD or GND
to configure the step resolution.
Your stepper will connect to 1A
, 1B
, 2A
and 2B
.
Connect power to VMOT
(do not forget to also connect ground of your stepper
power supply; see Voltages and Power).
See the datasheet for details about your driver.
What if it did not work?¶
Have a look at our hardware troubleshooting guide.