Hi.
I've been designing a bi polar step motor controller, based on the PIC 16F628 and the L293DNE IC. The plan is to control it with Linux CNC.
http://www.linuxcnc.org/
The output from Linux CNC's LPT is step and direction. One puls for each step. Direction is held LOW/HIGH.
I've made it on a breadboard, and need some feedback/thoughts/comments, before I start etching.
The program run through the steps according to the input. No "softstart" or PWM.
I've been designing a bi polar step motor controller, based on the PIC 16F628 and the L293DNE IC. The plan is to control it with Linux CNC.
http://www.linuxcnc.org/
The output from Linux CNC's LPT is step and direction. One puls for each step. Direction is held LOW/HIGH.
I've made it on a breadboard, and need some feedback/thoughts/comments, before I start etching.
The program run through the steps according to the input. No "softstart" or PWM.
Rich (BB code):
// Program : main_v3.c
// Description : Program to control bi polar step motor
// Compiler : Hi Tech C
// IDE : MPLAB v8.83
// Date : June 2012
// Author : nerdegutta
// WEB : www.nerdegutta.org
#include <htc.h>
#define _XTAL_FREQ 4000000
#define step1 5
#define step2 4
#define step3 6
#define step4 2
#define step5 10
#define step6 8
#define step7 9
#define step8 1
#define step RA0
#define dir RA1
#define stepDelay 7000
unsigned char stepPosition;
__CONFIG (FOSC_HS &
WDTE_ON &
PWRTE_ON &
MCLRE_OFF &
BOREN_OFF &
LVP_OFF &
CPD_OFF &
CP_OFF);
void main()
{
CMCON = 0x07;
TRISA = 0b00000011;
TRISB = 0b00000000;
PORTA = 0b00000000;
PORTB = 0b00000000;
stepPosition = 0;
while (1)
{
if (!dir) // check if dir pin is high,
{ // if it's high, go counterclockwise
if (step)
{
stepPosition++;
if (stepPosition > 8)
{
stepPosition = 1;
}
if (stepPosition == 1)
{
PORTB = step1;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 2)
{
PORTB = step2;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 3)
{
PORTB = step3;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 4)
{
PORTB = step4;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 5)
{
PORTB = step5;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 6)
{
PORTB = step6;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 7)
{
PORTB = step7;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 8)
{
PORTB = step8;
__delay_us(stepDelay);
PORTB = 0;
}
} // end if step
} // end if dir
if (dir) // check if dir pin is high
{ // if not high, go clockwise
if (step)
{
stepPosition--;
if (stepPosition < 1)
{
stepPosition = 8;
}
if (stepPosition == 8)
{
PORTB = step8;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 7)
{
PORTB = step7;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 6)
{
PORTB = step6;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 5)
{
PORTB = step5;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 4)
{
PORTB = step4;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 3)
{
PORTB = step3;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 2)
{
PORTB = step2;
__delay_us(stepDelay);
PORTB = 0;
}
if (stepPosition == 1)
{
PORTB = step1;
__delay_us(stepDelay);
PORTB = 0;
}
} // end if step
} // end if !dir
} // end while
} // end main
