ManuelW/grbl-LPC-CoreXY
1
0
Fork 0
Code Issues Pull Requests Releases 1 Wiki Activity

cleaned up stepper.c

Browse Source
This commit is contained in:
Simen Svale Skogsrud 2011-01-25 14:27:28 +01:00
parent 3a7ae13003
commit c8f71cf033
1 changed files with 14 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
stepper.c
View File

@ -46,13 +46,14 @@ uint8_t out_bits; // The next stepping-bits to be output
int32_t counter_x,
counter_y,
counter_z; // counter variables for the bresenham line tracer
uint32_t step_events_completed; // The count of step events executed in the current block
uint32_t step_events_completed; // The number of step events executed in the current block
volatile int busy; // TRUE when SIG_OUTPUT_COMPARE1A is being serviced. Used to avoid retriggering that handler.
// Variables used by the trapezoid generation
uint32_t cycles_per_step_event; // The number of machine cycles between each step event
uint32_t trapezoid_tick_cycle_counter; // The cycles since last trapezoid_tick used to generate ticks without
// allocating a separate timer
uint32_t trapezoid_rate; // The current rate of step_events according to the trapezoid generator
uint32_t trapezoid_tick_cycle_counter; // The cycles since last trapezoid_tick. Used to generate ticks at a steady
// pace without allocating a separate timer
uint32_t trapezoid_adjusted_rate; // The current rate of step_events according to the trapezoid generator
// Two trapezoids:
// __________________________
@ -67,16 +68,16 @@ uint32_t trapezoid_rate; // The current rate of step_events accord
// time ----->
//
// The trapezoid is the shape the speed curve over time. It starts at block->initial_rate, accelerates by block->rate_delta
// during the first block->accelerate_until step_events then keeps going at constant speed until the step-evet count reaches
// block->decelerate_after until the trapezoid generator is reset for the next block.
// during the first block->accelerate_until step_events_completed, then keeps going at constant speed until
// step_events_completed reaches block->decelerate_after after which it decelerates until the trapezoid generator is reset.
// The slope of acceleration is always +/- block->rate_delta and is applied at a constant rate by trapezoid_generator_tick()
// that is called ACCELERATION_TICKS_PER_SECOND times per second.
// Initializes the trapezoid generator from the current block. Called whenever a new
// block begins.
inline void trapezoid_generator_reset() {
trapezoid_rate = current_block->initial_rate;
set_step_events_per_minute(trapezoid_rate);
trapezoid_adjusted_rate = current_block->initial_rate;
set_step_events_per_minute(trapezoid_adjusted_rate);
}
// This is called ACCELERATION_TICKS_PER_SECOND times per second by the step_event
@ -85,15 +86,15 @@ inline void trapezoid_generator_reset() {
inline void trapezoid_generator_tick() {
if (current_block) {
if (step_events_completed < current_block->accelerate_until) {
trapezoid_rate += current_block->rate_delta;
set_step_events_per_minute(trapezoid_rate);
trapezoid_adjusted_rate += current_block->rate_delta;
set_step_events_per_minute(trapezoid_adjusted_rate);
} else if (step_events_completed > current_block->decelerate_after) {
// NOTE: We will only reduce speed if the result will be > 0. This catches small
// rounding errors that might leave steps hanging after the last trapezoid tick.
if(current_block->rate_delta < trapezoid_rate) {
trapezoid_rate -= current_block->rate_delta;
if(current_block->rate_delta < trapezoid_adjusted_rate) {
trapezoid_adjusted_rate -= current_block->rate_delta;
}
set_step_events_per_minute(trapezoid_rate);
set_step_events_per_minute(trapezoid_adjusted_rate);
}
}
}