Stepper Component¶
The stepper
component allows you to use stepper motors with ESPHome.
Currently only the A4988 stepper driver
(datasheet)
and ULN2003 (datasheet) are supported.
Note
This component will not show up in the Home Assistant front-end automatically because Home Assistant doesn’t have support for steppers. Please see Home Assistant Configuration.
Base Stepper Configuration¶
All stepper configuration schemas inherit these options.
Configuration variables:
max_speed (Required, float): The maximum speed in
steps/s
(steps per seconds) to drive the stepper at. Note most steppers can’t step properly with speeds higher than 250 steps/s.acceleration (Optional, float): The acceleration in
steps/s^2
(steps per seconds squared) to use when starting to move. The default isinf
which means infinite acceleration, so the stepper will try to drive with the full speed immediately. This value is helpful if that first motion of the motor is too jerky for what it’s moving. If you make this a small number, it will take the motor a moment to get up to speed.deceleration (Optional, float): The same as
acceleration
, but for when the motor is decelerating shortly before reaching the set position. Defaults toinf
(immediate deceleration).
A4988 Component¶
Put this code into the configuration file on ESPHome for this device.
stepper:
- platform: a4988
id: my_stepper
step_pin: D0
dir_pin: D1
max_speed: 250 steps/s
# Optional:
sleep_pin: D2
acceleration: inf
deceleration: inf
Configuration variables:
id (Required, ID): Specify the ID of the stepper so that you can control it.
step_pin (Required, Pin Schema): The
STEP
pin of the A4988 stepper driver.dir_pin (Required, Pin Schema): The
DIRECTION
pin of the A4988 stepper driver.sleep_pin (Optional, Pin Schema): Optionally also use the
SLEEP
pin of the A4988 stepper driver. If specified, the driver will be put into sleep mode as soon as the stepper reaches the target steps.All other from Base Stepper Configuration.
Note
If the stepper is driving in the wrong direction, you can invert the dir_pin
:
stepper:
- platform: a4988
# ...
dir_pin:
number: D1
inverted: true
ULN2003 Component¶
Put this code into the configuration file on ESPHome for this device.
# Example configuration entry
stepper:
- platform: uln2003
id: my_stepper
pin_a: D0
pin_b: D1
pin_c: D2
pin_d: D3
max_speed: 250 steps/s
# Optional:
acceleration: inf
deceleration: inf
Configuration variables:
id (Required, ID): Specify the ID of the stepper so that you can control it.
pin_a (Required, Pin Schema): The pin a of the stepper control board.
pin_b (Required, Pin Schema): The pin b of the stepper control board.
pin_c (Required, Pin Schema): The pin c of the stepper control board.
pin_d (Required, Pin Schema): The pin d of the stepper control board.
sleep_when_done (Optional, boolean): Whether to turn off all coils when the stepper has reached the target position
step_mode (Optional, string): The step mode to operate the motor with. One of:
FULL_STEP
(Default)HALF_STEP
WAVE_DRIVE
All other from Base Stepper Configuration.
stepper.set_target
Action¶
To use your stepper motor in automations or templates, you can use this action to set the target position (in steps). The stepper will always run towards the target position and stop once it has reached the target.
on_...:
then:
- stepper.set_target:
id: my_stepper
target: 250
# Templated
- stepper.set_target:
id: my_stepper
target: !lambda |-
if (id(my_binary_sensor).state) {
return 1000;
} else {
return -1000;
}
Configuration options:
id (Required, ID): The ID of the stepper.
target (Required, int, templatable): The target position in steps.
Warning
This turns the stepper to an absolute position! To have the servo move relative to the current position, first reset the current position and then set the target to the relative value.
on_...:
then:
# Move 150 steps forward
- stepper.report_position:
id: my_stepper
position: 0
- stepper.set_target:
id: my_stepper
target: 150
stepper.report_position
Action¶
All steppers start out with a target and current position of 0
on boot. However, if you for example want to home
a stepper motor, it can be useful to report the stepper where it is currently at.
With this action, you can set the stepper’s internal position counter to a specific value (in steps). Please note that reporting the position can create unexpected moves of the stepper. For example, if the stepper’s target and current position is at 1000 steps and you “report” a position of 0, the stepper will move 1000 steps forward to match the target again.
on_...:
then:
- stepper.report_position:
id: my_stepper
position: 250
# It's best to call set_target directly after report_position, so that the stepper doesn't move
- stepper.set_target:
id: my_stepper
target: 250
# Templated
- stepper.report_position:
id: my_stepper
position: !lambda |-
if (id(my_binary_sensor).state) {
return 0;
} else {
return -1000;
}
Configuration variables:
id (Required, ID): The ID of the stepper.
position (Required, int, templatable): The position to report in steps.
stepper.set_speed
Action¶
This Action allows you to set the speed of a stepper at runtime.
on_...:
- stepper.set_speed:
id: my_stepper
speed: 250 steps/s
Configuration variables:
id (Required, ID): The ID of the stepper.
speed (Required, templatable, float): The speed in
steps/s
(steps per seconds) to drive the stepper at.
stepper.set_acceleration
Action¶
This Action allows you to set the acceleration of a stepper at runtime.
on_...:
- stepper.set_acceleration:
id: my_stepper
acceleration: 250 steps/s^2
Configuration variables:
id (Required, ID): The ID of the stepper.
acceleration (Required, templatable, float): The acceleration in
steps/s^2
(steps per seconds squared) to use when starting to move.
stepper.set_deceleration
Action¶
This Action allows you to set the deceleration of a stepper at runtime.
on_...:
- stepper.set_deceleration:
id: my_stepper
deceleration: 250 steps/s^2
Configuration variables:
id (Required, ID): The ID of the stepper.
deceleration (Required, templatable, float): The same as
acceleration
, but for when the motor is decelerating shortly before reaching the set position.
Home Assistant Configuration¶
This component will not show up in the Home Assistant front-end (Overview) automatically because Home Assistant does not support steppers natively.
You can add the stepper component code below to your Home Assistant configuration (configuration.yaml
) to
be able to control the stepper from the front-end.
# Add a slider control to Home Assistant to set an integer value
input_number:
stepper_control:
name: Stepper Control
initial: 0
min: -1000
max: 1000
step: 1
mode: slider
# Do something when the slider changes
automation:
- alias: Write Stepper Value to ESP
trigger:
platform: state
entity_id: input_number.stepper_control
action:
# Replace livingroom with the name you gave the ESP
- service: esphome.livingroom_control_stepper
data_template:
target: '{{ trigger.to_state.state | int }}'
In the above code, “stepper_control” is the ID of a numeric input field. It must be unique and it is
used in the automation section as a reference name. The display name for this field is in
stepper_control’s name
key.
If you want your user interface to give you more control over your stepper controller, such as
setting the acceleration, deceleration, etc, then you can add more input fields after stepper_control
but before automation
. They can be a simple number-entry field (mode: box) or a slider like this.
Each of these extra input fields needs an associated input parameter defined on the ESPHome device’s
API service.
The automation section tells Home Assistant what to do when the slider changes. It needs a trigger
(state of the stepper_control
slider) and an action. In the trigger section, entity_id
must refer
back to the configuration ID that triggers the automation. For us, that is the stepper_control
field in the input_number
item. That’s why the value is input_number.stepper_control
.
In the action section, the service name is vital to get right: it’s the glue that connects Home Automation’s
front-end to the ESPHome device configuration. While you might expect the syntax to be esphome.<your_device>.<api_service>
,
the correct syntax is to join the device ID to the API service ID with an underscore,
as in esphome.livingroom_control_stepper
where “Livingroom” is a device in ESPHome and “control_stepper” is an
API service for that device.
The template string is used to get the “state” value from the target
field (defined in the target section) on the
input_number
component of the Home Assistant front-end. This value is then passed to the API service as defined in
the ESPHome device’s configuration. The data_template
section lists one value for each of the input parameters on
the service being called by the automation. In our case, the ESPHome device has an API service with a single parameter,
“target”. If you called this “my_target”, then the last line above should be my_target: '{{ trigger.to_state.state | int }}'
.
Getting this linkage right is very important.
The following code needs to go in the ESPHome configuration file for this device. Above, we mention “API service”
a lot. This code is where that is defined. You may have already added it (or something similar). Note
that the input variable for the control_stepper
service is called target
. That’s what matches with the
automation configuration above. Also note that the variable target
is defined as an integer. That means it
must be an integer number, not a string.
# ESPHome configuration
api:
services:
- service: control_stepper
variables:
target: int
then:
- stepper.set_target:
id: my_stepper
target: !lambda 'return target;'
stepper:
- platform: ...
# [...] stepper config
id: my_stepper
lambda calls¶
From lambdas, you can call several methods on stepper motors to do some advanced stuff (see the full API Reference for more info).
set_target
: Set the target position of the motor as an integer.// Argument is integer (signed int) // Set the (absolute) target position to 250 steps id(my_stepper).set_target(250);
report_position
: Report the current position as an integer.// Report the (absolute) current position as 250 steps id(my_stepper).report_position(250);
current_position
: Get the current position of the stepper as an integer.int pos = id(my_stepper).current_position;
target_position
: Get the set target position of the stepper as an integer.int pos = id(my_stepper).target_position;