motor.c

#include <bcm2835.h>
#include <stdio.h>


#define MOTOR_CS	RPI_V2_GPIO_P1_22
#define MOTOR_DIR	RPI_V2_GPIO_P1_24
#define MOTOR_STEP	RPI_V2_GPIO_P1_26

int help(char *command)
{
	printf("Steper motor driver based on Raspberry Pi + PIC (Version 1)\n");
	printf("Developed by Jesus Vasquez.\n");
	printf("Usage: %s <SPEED> <ACCE> <ACCE_F>\n Where:\n  <SPEED> 0 = 250 rpm; 1 = 125 rpm; ... ; 7 = 1,95 rpm.\n  <ACCE> 0 = without acceleration curve; 1 = with acceleration curve. and\n  <ACCE_F> = acceleration factor (1..5)\n", command);
	return 1;
}

int main(int argc, char **argv)
{

	uint8_t microstep_index, step_index;
	uint8_t direction = 0;
	uint8_t speed;
	uint16_t microstep_time;
	int microstep_count, microstep_togo, microstep_input;
	uint8_t speed_var = 8;
	uint16_t delay_var, delay_var_final;
	uint16_t speedchange_count = 0;
	uint8_t use_acceleration, acceleration_factor;

	char *speed_str[] = {"250 rpm", "125 rpm", "62,5 rpm", "31,25 rpm", "15,64 rpm", "7,81 rpm", "3,91 rpm", "1,95 rpm"};

	if (argc != 4)
		return help(argv[0]);

	speed = atoi(argv[1]); 
	if (speed > 7)
		return help(argv[0]);

	use_acceleration = atoi(argv[2]);
	if (use_acceleration > 1)
		return help(argv[0]);

	acceleration_factor = atoi(argv[3]); 
	if ((acceleration_factor  < 1) | (acceleration_factor  > 5))
		return help(argv[0]);

    if (!bcm2835_init())
    {
    	printf("Error during BCM2835_INIT() function\n");
		return 1;
	}

	if (use_acceleration)
	{
		delay_var = 128;
		delay_var_final = (1 << speed);
	}
	else
		delay_var = (1 << speed);

	microstep_time = 150 * delay_var;

	printf("Steper motor driver based on Raspberry Pi + PIC (Version 1)\n");
	printf("Developed by Jesus Vasquez.\n");
	printf("Speed selected = %s\n", speed_str[speed]);
	printf("Use acceleration curve = %d\n", use_acceleration);
	printf("Acceleration factor = %d\n", acceleration_factor);

    // Set the pin to be an output
    bcm2835_gpio_fsel(MOTOR_CS, BCM2835_GPIO_FSEL_OUTP);
    bcm2835_gpio_fsel(MOTOR_DIR, BCM2835_GPIO_FSEL_OUTP);
    bcm2835_gpio_fsel(MOTOR_STEP, BCM2835_GPIO_FSEL_OUTP);

    microstep_count = 0;
    microstep_togo = 0;

    bcm2835_gpio_write(MOTOR_CS, HIGH);

    while (1)
    {


		if (microstep_count != microstep_togo)
		{
			bcm2835_gpio_write(MOTOR_CS, LOW);

			direction = (microstep_count < microstep_togo);
			bcm2835_gpio_write(MOTOR_DIR, direction);

			bcm2835_gpio_write(MOTOR_STEP, HIGH);
			bcm2835_delayMicroseconds(microstep_time);
			bcm2835_gpio_write(MOTOR_STEP, LOW);
			bcm2835_delayMicroseconds(microstep_time);

			if(direction)
				microstep_count++;
			else
				microstep_count--;

			if (use_acceleration)
			{
				if (delay_var > delay_var_final)
				{
					speedchange_count += 10;
					if (speedchange_count >= acceleration_factor)
					{
						speedchange_count = 0;
						delay_var--;
						microstep_time = 150 * delay_var;
					}
				}
			}

		}
		else
		{
			bcm2835_gpio_write(MOTOR_CS, HIGH);
			printf("Current position: %d\n", microstep_count);
			printf("Number of microstep to go?: ");
			scanf("%d",&microstep_input);
			microstep_togo += microstep_input;
			printf("Going to position %d ...\n\n", microstep_togo);

			if (use_acceleration)
			{
				if (speed < 8)
					delay_var = 256;
				else
					delay_var = (1 << speed);

				delay_var_final = (1 << speed);
				
				microstep_time = 150 * delay_var;
			}
				
		}
		
    }
    bcm2835_close();
    return 0;
}