Silicon Laboratories Stepper Machine Bedienungsanleitung PDF herunterladen (Seite 29)

AN155

Rev. 1.1 29

{

if (target > Position)

{

Forward = 1; // set forward flag

length = target - Position; // subtract smaller (position)

}

else

{

Forward = 0; // clear forward flag

length = Position - target; // subtract smaller (target)

}

if (length < 1024) // if short move

MaxTableIndex = length>>2; // divide length by 4

else

MaxTableIndex = 0xff; // else max is 255

SlewCount = length; // build value in SlewCount

SlewCount -= MaxTableIndex; // subtract MaxTableIndex twice

SlewCount -= MaxTableIndex;

SlewCount--; // Subtract one to account first step

TableIndex = 0; // init table index

motorState = ACCELERATE; // init motor state

TL0 = -100; // move starts in 100 ticks

TH0 = 0xFF; // extend sign

LED = ON; // turn on LED

ET0 = 1; // enable Timer0 interrupts

TR0 = 1; // start Timer0

}

else

{

doneFlag=1; // if done display message

}

//-----------------------------------------------------------------------------

// Timer_ISR()

// This is the timer interrupt service routine for the stepper motor.

// First the PatternIndex and Position are incremented or decremented

// depending on the direction of the motor. Then the new pattern is

// output to the stepper motor. Nested if..else statements are used to

// determine the if the motor is in the acceleration, slewing, or

// deceleration phase. The TableIndex and SlewCount are modified

// accordingly. When the move is complete, further output compares and

// interrupts are disabled.

void Timer_ISR (void) interrupt 1

{

unsigned char TableValue;

unsigned int offset;

udblbyte time;

if (Forward) // if forward

{

PatternIndex++; // increment step pattern

PatternIndex &= 0x07; // fix modulus 8 counter

Position++; // increment Position

}

else

{

PatternIndex--; // decrement step pattern

1 2 ... 24 25 26 27 28 29 30 31 32 33 34 35 36

Kommentare zu diesen Handbüchern

Keine Kommentare

Silicon Laboratories Stepper Machine Bedienungsanleitung Seite 29

Kommentare zu diesen Handbüchern

Verwandte Produkte und Handbücher für Stepper Silicon Laboratories Stepper Machine