Stepper Motor (stepper)

Stepper motor.

Device Type

DEVICE_TYPE_STEPPER

Structure

struct stepper_t {
    char * name;
    int (*enable)(struct stepper_t * stepper);
    int (*disable)(struct stepper_t * stepper);
    int (*move)(struct stepper_t * stepper, int step, int speed);
    int (*busying)(struct stepper_t * stepper);
    void * priv;
};

Key API

Function	Description
search_stepper(name)	Find stepper motor by name
register_stepper(stepper, drv)	Register a stepper motor
unregister_stepper(stepper)	Unregister a stepper motor
stepper_enable/disable(stepper)	Enable/disable
stepper_move(stepper, step, speed)	Move specified number of steps
stepper_busying(stepper)	Query if busy

Driver Implementations

stepper-bipolar-gpio

Bipolar stepper motor GPIO driver. Controls a bipolar stepper motor via an H-bridge using 4 GPIOs (PA, NA, PB, NB). Supports three drive modes:

Mode	drive-mode value	Description
Wave drive	wave	Energizes one phase at a time, 4-step cycle, lower torque
Full step drive	fullstep	Energizes two phases at a time, 4-step cycle, higher torque
Half step drive	halfstep	Alternates single/dual phase excitation, 8-step cycle, doubled resolution

Device tree configuration properties:

Property	Type	Required	Description
drive-mode	string	No	Drive mode: wave, fullstep, halfstep, default wave
pa-gpio	int	Yes	Phase A positive GPIO
pa-gpio-config	int	No	Phase A positive GPIO config
na-gpio	int	Yes	Phase A negative GPIO
na-gpio-config	int	No	Phase A negative GPIO config
pb-gpio	int	Yes	Phase B positive GPIO
pb-gpio-config	int	No	Phase B positive GPIO config
nb-gpio	int	Yes	Phase B negative GPIO
nb-gpio-config	int	No	Phase B negative GPIO config
default-speed	int	No	Default speed (steps/sec), default 100

Device tree example:

{
    "bipolar-stepper": {
        "type": "stepper-bipolar-gpio",
        "drive-mode": "halfstep",
        "pa-gpio": 0,
        "na-gpio": 1,
        "pb-gpio": 2,
        "nb-gpio": 3,
        "default-speed": 200
    }
}

stepper-unipolar-gpio

Unipolar stepper motor GPIO driver. Directly drives a unipolar (5-wire or 6-wire) stepper motor using 4 GPIOs (A, B, C, D). Supports three drive modes:

Mode	drive-mode value	Description
Wave drive	wave	Energizes one phase at a time, 4-step cycle, lower torque
Full step drive	fullstep	Energizes two phases at a time, 4-step cycle, higher torque
Half step drive	halfstep	Alternates single/dual phase excitation, 8-step cycle, doubled resolution

Device tree configuration properties:

Property	Type	Required	Description
drive-mode	string	No	Drive mode: wave, fullstep, halfstep, default wave
a-gpio	int	Yes	Phase A GPIO
a-gpio-config	int	No	Phase A GPIO config
b-gpio	int	Yes	Phase B GPIO
b-gpio-config	int	No	Phase B GPIO config
c-gpio	int	Yes	Phase C GPIO
c-gpio-config	int	No	Phase C GPIO config
d-gpio	int	Yes	Phase D GPIO
d-gpio-config	int	No	Phase D GPIO config
default-speed	int	No	Default speed (steps/sec), default 100

Device tree example:

{
    "unipolar-stepper": {
        "type": "stepper-unipolar-gpio",
        "drive-mode": "fullstep",
        "a-gpio": 10,
        "b-gpio": 11,
        "c-gpio": 12,
        "d-gpio": 13,
        "default-speed": 150
    }
}

stepper-pluse-dir

Pulse/Direction stepper motor GPIO driver. Used to control stepper motors with external drivers (e.g., TB6600, DM542). Controls motor rotation via pulse and direction signals, with each pulse corresponding to one step. Supports signal polarity inversion configuration.

Device tree configuration properties:

Property	Type	Required	Description
pluse-gpio	int	Yes	Pulse signal GPIO
pluse-gpio-config	int	No	Pulse GPIO config
pluse-gpio-inverted	int	No	Pulse signal polarity inversion, default 0
dir-gpio	int	No	Direction signal GPIO (-1 for unused)
dir-gpio-config	int	No	Direction GPIO config
dir-gpio-inverted	int	No	Direction signal polarity inversion, default 0
enable-gpio	int	No	Enable signal GPIO (-1 for unused)
enable-gpio-config	int	No	Enable GPIO config
enable-gpio-inverted	int	No	Enable signal polarity inversion, default 0
default-speed	int	No	Default speed (steps/sec), default 100

Device tree example:

{
    "pluse-dir-stepper": {
        "type": "stepper-pluse-dir",
        "pluse-gpio": 20,
        "pluse-gpio-inverted": 0,
        "dir-gpio": 21,
        "dir-gpio-inverted": 0,
        "enable-gpio": 22,
        "enable-gpio-inverted": 1,
        "default-speed": 500
    }
}

Description

Stepper motor control interface. Moves by a specified number of steps at a given speed, supports busy status query. Used in 3D printers and CNC machines.

• Bipolar: 4-wire stepper motor, requires H-bridge driver, direction controlled by current polarity
• Unipolar: 5/6-wire stepper motor, uses Darlington array drivers (e.g., ULN2003), single-direction current per phase
• Pulse/Direction: Works with external stepper motor drivers, requires only pulse and direction signals, suitable for high-power applications