motor.h File Reference

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Macros
#define	MIN_COMMAND   1
#define	MAX_COMMAND   100

Enumerations
enum	motor_t { MOTOR_LEFT = 0U, MOTOR_RIGHT = 1U }
	Alias to select the motor to work on. More...
enum	motor_direction_t { FORWARD = 0U, BACKWARD = 1U }
	Alias for motor rotation sense. More...
enum	motor_sense_t { DIRECTION_1 = 0U, DIRECTION_2 = 1U }
	Alias for motor orientation. More...

Functions
void	motor_init (motor_sense_t motor_left_forward_sense, motor_sense_t motor_right_forward_sense)
	Initialise the motor driver. More...
int	motor_set_speed (motor_t motor, uint8_t speed)
	Set the rotation speed of the specified motor. More...
int8_t	motor_get_speed (motor_t motor)
	Get the rotation speed of the specified motor. More...
motor_direction_t	motor_get_direction (motor_t motor)
	Get the current rotation direction of the specified motor. More...
int	motor_set_direction (motor_t motor, motor_direction_t direction)
	Set the rotation direction of the specified motor. More...
void	motor_toggle_direction (motor_t motor)
	Revert the rotation direction of the specified motor. More...

Macro Definition Documentation

MAX_COMMAND

#define MAX_COMMAND   100

Maximum possible value for commands

Definition at line 11 of file motor.h.

MIN_COMMAND

#define MIN_COMMAND   1

Minimal value that makes the robot move

Definition at line 9 of file motor.h.

Enumeration Type Documentation

motor_direction_t

enum motor_direction_t

Alias for motor rotation sense.

Enumerator
FORWARD	Motor turns so that robot moves forward
BACKWARD	Motor turns so that robot moves backward

Definition at line 28 of file motor.h.

motor_sense_t

enum motor_sense_t

Alias for motor orientation.

Remarks

These values allow to hide mechanical differences in motor installation so that a FORWARD move makes the motor turn in the proper sense. Values are totally arbitrary.

Enumerator
DIRECTION_1	Value 1
DIRECTION_2	Value 2

Definition at line 40 of file motor.h.

motor_t

enum motor_t

Alias to select the motor to work on.

Remarks

The meaning of the value "LEFT" and "RIGHT" is not necessarily coherent with the actual mechanical organization of the robot, it depends on initial user choice.

Enumerator
MOTOR_LEFT	Left motor
MOTOR_RIGHT	Right motor

Definition at line 20 of file motor.h.

Function Documentation

motor_get_direction()

motor_direction_t motor_get_direction

(

motor_t

motor

)

Get the current rotation direction of the specified motor.

Parameters

[in]

motor

The motor to look at.

Returns

The current rotation direction of the specified motor.

Return values

FORWARD/BACKWARD
-1	Invalid 'motor' parameter.

Definition at line 114 of file motor.c.

motor_get_speed()

int8_t motor_get_speed

(

motor_t

motor

)

Get the rotation speed of the specified motor.

Parameters

[in]

motor

The motor to get the speed of.

Returns

The rotation speed of the specified motor or -1 in case of error.

Definition at line 103 of file motor.c.

motor_init()

void motor_init	(	motor_sense_t	motor_left_forward_sense,
		motor_sense_t	motor_right_forward_sense
	)

Initialise the motor driver.

This function is in charge of enabling all the low-level components used to control the motors. It configures the timers used to generate the PWM and starts them. It also sets the direction pins so that the motors turn forward as defined by the parameters.

Parameters

[in]	motor_left_forward_sense	The rotation direction which corresponds to a forward movement of the left motor.
[in]	motor_right_forward_sense	The rotation direction which corresponds to a forward movement of the right motor.

Note

To provide a high-level interface to control the motors, this driver uses the values FORWARD and BACKWARD to describe the rotation direction of the motors. However, these directions depend on how the motors are placed in the robot and how they are wired on the H-bridge. In order to foster reusability of this driver, the mapping between pins state and rotation direction is settable. The 2 parameters of this init function are for this purpose. DIRECTION_1 corresponds to PIN_A at '1' (+3V3) and PIN_B at '0' (GND). DIRECTION_2 corresponds to PIN_A at '0' (GND) and PIN_B at '1' (+3V3).

Warning

This function must be called first to start the motor driver.

Definition at line 48 of file motor.c.

motor_set_direction()

int motor_set_direction	(	motor_t	motor,
		motor_direction_t	direction
	)

Set the rotation direction of the specified motor.

Parameters

[in]	motor	To motor to set the direction of.
[in]	direction	The requested rotation direction.

Returns

An int indicating success, else an error code.

Return values

0	Success.
-1	Invalid 'motor' parameter.
-2	Invalid 'direction' parameter (out of range).

Definition at line 123 of file motor.c.

motor_set_speed()

int motor_set_speed	(	motor_t	motor,
		uint8_t	speed
	)

Set the rotation speed of the specified motor.

Parameters

[in]	motor	The motor to change the speed of.
[in]	speed	The requested speed. Allowed range is [0,MAX_COMMAND]. Be careful that a minimum non-zero value (MIN_COMMAND) is required for the robot to move.

Returns

An int indicating success, else an error code.

Return values

0	Success.
-1	Invalid 'motor' parameter.
-2	Invalid 'speed' parameter (out of range).

Definition at line 77 of file motor.c.

motor_toggle_direction()

void motor_toggle_direction

(

motor_t

motor

)

Revert the rotation direction of the specified motor.

Parameters

[in]

motor

To motor to change the rotation direction of.

Definition at line 145 of file motor.c.