ManuelW/grbl-LPC-CoreXY
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fixed buffering of pace changes and general cleaning

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This commit is contained in:
Simen Svale Skogsrud
2009-02-08 20:40:24 +01:00
parent 8a0c9fd180
commit c07a322589
5 changed files with 64 additions and 44 deletions
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46
stepper.c
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@ -35,24 +35,34 @@
volatile uint8_t step_buffer[STEP_BUFFER_SIZE]; // A buffer for step instructions
volatile int step_buffer_head = 0;
volatile int step_buffer_tail = 0;
volatile uint32_t current_pace;
volatile uint32_t next_pace = 0;
uint8_t stepper_mode = STEPPER_MODE_STOPPED;
uint8_t echo_steps = true;
void config_pace_timer(uint32_t microseconds);
// This timer interrupt is executed at the pace set with set_pace. It pops one instruction from
// the step_buffer, executes it. Then it starts timer2 in order to reset the motor port after
// five microseconds.
SIGNAL(SIG_OUTPUT_COMPARE1A)
{
if (step_buffer_head != step_buffer_tail) {
// Set the direction pins a nanosecond or two before you step the steppers
STEPPING_PORT = (STEPPING_PORT & ~DIRECTION_MASK) | (step_buffer[step_buffer_tail] & DIRECTION_MASK);
// Then pulse the stepping pins
STEPPING_PORT = (STEPPING_PORT & ~STEP_MASK) | step_buffer[step_buffer_tail];
// Reset and start timer 2 which will reset the motor port after 5 microsecond
TCNT2 = 0; // reset counter
OCR2A = 5*TICKS_PER_MICROSECOND; // set the time
TIMSK2 |= (1<<OCIE2A); // enable interrupt
if(step_buffer[step_buffer_tail] == 0xff) {
// If this is not a step-instruction, but a pace-marker: change pace
config_pace_timer(next_pace);
next_pace = 0;
} else {
// Set the direction pins a nanosecond or two before you step the steppers
STEPPING_PORT = (STEPPING_PORT & ~DIRECTION_MASK) | (step_buffer[step_buffer_tail] & DIRECTION_MASK);
// Then pulse the stepping pins
STEPPING_PORT = (STEPPING_PORT & ~STEP_MASK) | step_buffer[step_buffer_tail];
// Reset and start timer 2 which will reset the motor port after 5 microsecond
TCNT2 = 0; // reset counter
OCR2A = 5*TICKS_PER_MICROSECOND; // set the time
TIMSK2 |= (1<<OCIE2A); // enable interrupt
}
// move the step buffer tail to the next instruction
step_buffer_tail = (step_buffer_tail + 1) % STEP_BUFFER_SIZE;
}
@ -92,7 +102,7 @@ void st_init()
sei();
// start off with a slow pace
st_set_pace(20000);
config_pace_timer(20000);
st_start();
}
@ -148,11 +158,20 @@ inline void st_stop()
stepper_mode = STEPPER_MODE_STOPPED;
}
void st_set_pace(uint32_t microseconds)
void st_buffer_pace(uint32_t microseconds)
{
// Do nothing if the pace in unchanged
if (current_pace == microseconds) { return; }
// If the one-element pace buffer is full, flush step buffer
if (next_pace != 0) {
st_synchronize();
}
next_pace = microseconds;
st_buffer_step(0xff);
}
void config_pace_timer(uint32_t microseconds)
{
printString("pace = ");
printInteger(microseconds);
printString("\n\r");
uint32_t ticks = microseconds*TICKS_PER_MICROSECOND;
uint16_t ceiling;
uint16_t prescaler;
@ -180,6 +199,7 @@ void st_set_pace(uint32_t microseconds)
TCCR1B = (TCCR1B & ~(0x07<<CS10)) | ((prescaler+1)<<CS10);
// Set ceiling
OCR1A = ceiling;
current_pace = microseconds;
}
int check_limit_switches()