Detailed Description

Dual stepper motor actutor.

===========================================================================

The Stepper header file should be included in an application as follows:

The ULN2003 BoosterPack can have two stepper motors connected to it. Stepper module can be interfaced with HC595(shift register) to perform operations such as single step movement or rotation.

Stepper uses output from ULN2003 which is driven by a shift register. A stepper motor can work in 3 different modes which are Fullstep, Halfstep and Wavedrive which in turn affect the power usage and the desired resolution of the motor. The Stepper module also supports movement in 2 different directions i.e. Clockwise and AntiClockwise.

The APIs in this driver serve as an interface to a DPL(Driver Porting Layer) The specific implementations are responsible for creating all the RTOS specific primitives to allow for thread-safe operation.

This driver has no dynamic memory allocation.

The Stepper_config array should contain pointers to a defined Stepper_HWAttrs and allocated array for the Stepper_Object structures. Stepper_init() must be called prior to using Stepper_open().

Defining Stepper_Config, Stepper_Object and Stepper_HWAttrs

Each structure must be defined by the application. The following example is for a MSP432 in which one ULN2003 BoosterPack is setup. One ULN2003 BoosterPack can be connected to two stepper motors which can be controlled using a single Stepper module. The following declarations are placed in "MSP_EXP432P401R.h" and "MSP_EXP432P401R.c" respectively. How the gpioIndices are defined are detailed in the next example.

"MSP_EXP432P401R.h"

typedef enum MSP_EXP432P401R_StepperName {
    MSP_EXP432P401R_Stepper_0 = 0, //Stepper number 1 on LaunchPad
    MSP_EXP432P401R_StepperCOUNT   //Total number of Steppers on the board
} MSP_EXP432P401R_StepperName;

"MSP_EXP432P401R.c"

 #include <ti/sail/stepper/stepper.h>
 Stepper_Object Stepper_object[MSP_EXP432P401R_StepperCOUNT];
 const Stepper_HWAttrs Stepper_hwAttrs[MSP_EXP432P401R_StepperCOUNT] = {
     {
        .HC595Index = MSP_EXP432P401R_HC595_0,
     },
 };
const Stepper_Config Stepper_config[] = {
    {
     .hwAttrs = &Stepper_hwAttrs[0],
     .object =  &Stepper_object[0],
    },
    {NULL, NULL}
 };

Opening a Stepper with default parameters

The Stepper_open() call must be made in a task context.

#include <ti/sail/stepper/stepper.h>
Stepper_Handle StepperHandle;
Stepper_initParams(&StepperParams);
StepperHandle = Stepper_open(0,&StepperParams)

#include <stdint.h>
#include <stdbool.h>
#include <unistd.h>
#include <stddef.h>
#include <ti/drivers/GPIO.h>
#include <ti/sail/hc595/hc595.h>

Go to the source code of this file.

Data Structures
struct	Stepper_Motor
	This structure contains the properties of a motor. More...

struct	Stepper_HWAttrs
	Hardware specific settings for a Stepper module. More...

struct	Stepper_Object
	Stepper Object structure. More...

struct	Stepper_Config
	Stepper configuration. More...

struct	Stepper_Params
	Stepper Parameters. More...

Typedefs
typedef struct Stepper_Config *	Stepper_Handle
	A handle that is returned from a HC595_open() call. More...

typedef enum Stepper_workMode	Stepper_workMode
	Stepper Workmodes types based on control method. More...

typedef enum Stepper_direction	Stepper_direction
	Stepper motor direction options. More...

typedef enum Stepper_motorEnum	Stepper_motorEnum
	Enumeration for number of the motor controlled by Stepper. More...

typedef struct Stepper_Motor	Stepper_Motor
	This structure contains the properties of a motor. More...

typedef struct Stepper_HWAttrs	Stepper_HWAttrs
	Hardware specific settings for a Stepper module. More...

typedef struct Stepper_Object	Stepper_Object
	Stepper Object structure. More...

typedef struct Stepper_Config	Stepper_Config
	Stepper configuration. More...

typedef struct Stepper_Params	Stepper_Params
	Stepper Parameters. More...

Enumerations
enum	Stepper_workMode { Stepper_workMode_fullStep = 0U, Stepper_workMode_halfStep = 1U, Stepper_workMode_waveDrive = 2U }
	Stepper Workmodes types based on control method. More...

enum	Stepper_direction { Stepper_direction_CW = 0U, Stepper_direction_CCW = 1U }
	Stepper motor direction options. More...

enum	Stepper_motorEnum { Stepper_motorEnum_motor1 = 0U, Stepper_motorEnum_motor2 = 1U, Stepper_motorEnum_all = 2U }
	Enumeration for number of the motor controlled by Stepper. More...

Functions
void	Stepper_initParams (Stepper_Params *params)
	Function to initialize a Stepper_Params struct to its defaults. More...

Stepper_Handle	Stepper_open (unsigned int StepperIndex, Stepper_Params *params)
	Function to open an instance of Stepper. More...

bool	Stepper_close (Stepper_Handle StepperHandle)
	Function to close a Stepper specified by the Stepper handle. More...

void	Stepper_init ()
	Function to initialize Stepper driver. More...

bool	Stepper_step (Stepper_Handle StepperHandle, Stepper_motorEnum motorNum, Stepper_direction direction)
	Function to move the stepper motors. More...

bool	Stepper_setWorkMode (Stepper_Handle StepperHandle, Stepper_motorEnum motorNum, Stepper_workMode mode)
	Function to change the workmode of a motor. More...

Stepper_workMode	Stepper_getMotorMode (Stepper_Handle StepperHandle, Stepper_motorEnum motorNum)
	Function to get current workmode of a motor. More...

Typedef Documentation

§ Stepper_Handle

typedef struct Stepper_Config* Stepper_Handle

A handle that is returned from a HC595_open() call.

§ Stepper_workMode

typedef enum Stepper_workMode Stepper_workMode

Stepper Workmodes types based on control method.

A Stepper motor can be run in one of the 3 different modes i.e. Fullstep, Halfstep and Wavedrive.

§ Stepper_direction

typedef enum Stepper_direction Stepper_direction

Stepper motor direction options.

A Stepper motor can be moved in either of the two directions clockwise or anti-clockwise.

§ Stepper_motorEnum

typedef enum Stepper_motorEnum Stepper_motorEnum

Enumeration for number of the motor controlled by Stepper.

A single instance of Stepper can control two motors numbered 1 and 2

§ Stepper_Motor

typedef struct Stepper_Motor Stepper_Motor

This structure contains the properties of a motor.

Each motor can operate asynchronously in a different mode.

§ Stepper_HWAttrs

typedef struct Stepper_HWAttrs Stepper_HWAttrs

Hardware specific settings for a Stepper module.

This structure should be defined and provided by the application. The gpioIndex should be defined in accordance of the GPIO driver. The pin must be configured as GPIO_CFG_INPUT and GPIO_CFG_IN_INT_FALLING.

§ Stepper_Object

typedef struct Stepper_Object Stepper_Object

Stepper Object structure.

The application must not access any member variables of this structure!

§ Stepper_Config

typedef struct Stepper_Config Stepper_Config

Stepper configuration.

The Stepper_Config structure contains a set of pointers used to characterize the Stepper driver implementation.

This structure needs to be defined and provided by the application and will be NULL terminated.

§ Stepper_Params

typedef struct Stepper_Params Stepper_Params

Stepper Parameters.

Stepper parameters are used with the Stepper_open() call. Default values for these parameters are set using Stepper_initParams(). It contains the workmodes for two motors connected to ULN2003 BoosterPack.

See also: Stepper_initParams()

Enumeration Type Documentation

§ Stepper_workMode

enum Stepper_workMode

Stepper Workmodes types based on control method.

A Stepper motor can be run in one of the 3 different modes i.e. Fullstep, Halfstep and Wavedrive.

Enumerator
Stepper_workMode_fullStep
Stepper_workMode_halfStep
Stepper_workMode_waveDrive

§ Stepper_direction

enum Stepper_direction

Stepper motor direction options.

A Stepper motor can be moved in either of the two directions clockwise or anti-clockwise.

Enumerator
Stepper_direction_CW
Stepper_direction_CCW

§ Stepper_motorEnum

enum Stepper_motorEnum

Enumeration for number of the motor controlled by Stepper.

A single instance of Stepper can control two motors numbered 1 and 2

Enumerator
Stepper_motorEnum_motor1	step motor1
Stepper_motorEnum_motor2	step motor2
Stepper_motorEnum_all	step both motors together

Function Documentation

§ Stepper_initParams()

void Stepper_initParams ( Stepper_Params * params )

Function to initialize a Stepper_Params struct to its defaults.

Parameters

params A pointer to Stepper_Params structure for initialization.

Default values are: motor1mode = Stepper_workMode_fullStep; motor2mode = Stepper_workMode_halfStep;

References Stepper_defaultParams.

§ Stepper_open()

Stepper_Handle Stepper_open	(	unsigned int	StepperIndex,
		Stepper_Params *	params
	)

Function to open an instance of Stepper.

Function to initialize a given Stepper specified by the particular index value.

Precondition: Stepper_init() has to be called first

Parameters

StepperIndex	Logical Stepper number indexed into the Stepper_config table
*params	A pointer to Stepper_Params structure. If NULL, it will use default values.

Returns: A Stepper_Handle on success, or a NULL on failure.

See also: Stepper_init(); Stepper_initParams(); Stepper_close()

References HC595_open(), Stepper_HWAttrs::HC595Index, Stepper_Config::hwAttrs, Stepper_Motor::motorMode, Stepper_Params::motorNumMode, Stepper_Object::motors, Stepper_Config::object, Stepper_Object::shiftHandle, Stepper_count, Stepper_motorEnum_motor1, and Stepper_motorEnum_motor2.

§ Stepper_close()

bool Stepper_close ( Stepper_Handle StepperHandle )

Function to close a Stepper specified by the Stepper handle.

The Stepper close API to close the Stepper instance specified by StepperHandle.

This call will destruct associated timer if running and turn off Stepper, can be hooked up with Power Down sequence in system.

Precondition: Stepper_open() had to be called first.

Parameters

StepperHandle A Stepper_Handle returned from Stepper_open()

§ Stepper_init()

void Stepper_init ( )

Function to initialize Stepper driver.

This function will initialize the Stepper driver.

§ Stepper_step()

bool Stepper_step	(	Stepper_Handle	StepperHandle,
		Stepper_motorEnum	motorNum,
		Stepper_direction	direction
	)

Function to move the stepper motors.

Precondition: Stepper_open() had to be called first.

Parameters

StepperHandle	A Stepper_Handle returned from Stepper_open().
motorNum	A enumeration describing the motor no. i.e. motor1 or motor2.
direction	It is the direction of rotation of motor.

Returns: true if motor can step else return false

References HC595_shift(), Stepper_Motor::motorMode, Stepper_Object::motors, Stepper_Config::object, Stepper_Object::shiftHandle, Stepper_direction_CW, Stepper_motorEnum_all, Stepper_motorEnum_motor1, Stepper_motorEnum_motor2, and workMode.

§ Stepper_setWorkMode()

bool Stepper_setWorkMode	(	Stepper_Handle	StepperHandle,
		Stepper_motorEnum	motorNum,
		Stepper_workMode	mode
	)

Function to change the workmode of a motor.

Precondition: Stepper_open() had to be called first.

Parameters

StepperHandle	A Stepper_Handle returned from Stepper_open().
motorNum	A enumeration describing the motor no. i.e. motor1 or motor2.
mode	It is the Workmode that the user wants to set.

Returns: true if motor can step else return false

References HC595_clear(), Stepper_Motor::motorMode, Stepper_Object::motors, Stepper_Config::object, and Stepper_Object::shiftHandle.

§ Stepper_getMotorMode()

Stepper_workMode Stepper_getMotorMode	(	Stepper_Handle	StepperHandle,
		Stepper_motorEnum	motorNum
	)

Function to get current workmode of a motor.

Precondition: Stepper_open() had to be called first.

Parameters

StepperHandle	A Stepper_Handle returned from Stepper_open().
motorNum	A enumeration describing the motor no. i.e. motor1 or motor2.

Returns: A Stepper_workMode on success, or a NULL on failure.

References Stepper_Motor::motorMode, Stepper_Object::motors, and Stepper_Config::object.

Detailed Description

Defining Stepper_Config, Stepper_Object and Stepper_HWAttrs

Opening a Stepper with default parameters

Data Structures

Typedefs

Enumerations

Functions

Typedef Documentation

§ Stepper_Handle

§ Stepper_workMode

§ Stepper_direction

§ Stepper_motorEnum

§ Stepper_Motor

§ Stepper_HWAttrs

§ Stepper_Object

§ Stepper_Config

§ Stepper_Params

Enumeration Type Documentation

§ Stepper_workMode

§ Stepper_direction

§ Stepper_motorEnum

Function Documentation

§ Stepper_initParams()

§ Stepper_open()

§ Stepper_close()

§ Stepper_init()

§ Stepper_step()

§ Stepper_setWorkMode()

§ Stepper_getMotorMode()