Marlin 2.0 for Flying Bear 4S/5
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/**
* Marlin 3D Printer Firmware
* Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
*
* Based on Sprinter and grbl.
* Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* planner.cpp
*
* Buffer movement commands and manage the acceleration profile plan
*
* Derived from Grbl
* Copyright (c) 2009-2011 Simen Svale Skogsrud
*
* The ring buffer implementation gleaned from the wiring_serial library by David A. Mellis.
*
*
* Reasoning behind the mathematics in this module (in the key of 'Mathematica'):
*
* s == speed, a == acceleration, t == time, d == distance
*
* Basic definitions:
* Speed[s_, a_, t_] := s + (a*t)
* Travel[s_, a_, t_] := Integrate[Speed[s, a, t], t]
*
* Distance to reach a specific speed with a constant acceleration:
* Solve[{Speed[s, a, t] == m, Travel[s, a, t] == d}, d, t]
* d -> (m^2 - s^2)/(2 a) --> estimate_acceleration_distance()
*
* Speed after a given distance of travel with constant acceleration:
* Solve[{Speed[s, a, t] == m, Travel[s, a, t] == d}, m, t]
* m -> Sqrt[2 a d + s^2]
*
* DestinationSpeed[s_, a_, d_] := Sqrt[2 a d + s^2]
*
* When to start braking (di) to reach a specified destination speed (s2) after accelerating
* from initial speed s1 without ever stopping at a plateau:
* Solve[{DestinationSpeed[s1, a, di] == DestinationSpeed[s2, a, d - di]}, di]
* di -> (2 a d - s1^2 + s2^2)/(4 a) --> intersection_distance()
*
* IntersectionDistance[s1_, s2_, a_, d_] := (2 a d - s1^2 + s2^2)/(4 a)
*
* --
*
* The fast inverse function needed for Bézier interpolation for AVR
* was designed, written and tested by Eduardo José Tagle on April/2018
*/
#include "planner.h"
#include "stepper.h"
#include "motion.h"
#include "../module/temperature.h"
#include "../lcd/ultralcd.h"
#include "../core/language.h"
#include "../gcode/parser.h"
#include "../Marlin.h"
#if HAS_LEVELING
#include "../feature/bedlevel/bedlevel.h"
#endif
#if ENABLED(FILAMENT_WIDTH_SENSOR)
#include "../feature/filwidth.h"
#endif
#if ENABLED(BARICUDA)
#include "../feature/baricuda.h"
#endif
#if ENABLED(MIXING_EXTRUDER)
#include "../feature/mixing.h"
#endif
#if ENABLED(AUTO_POWER_CONTROL)
#include "../feature/power.h"
#endif
Planner planner;
// public:
/**
* A ring buffer of moves described in steps
*/
block_t Planner::block_buffer[BLOCK_BUFFER_SIZE];
volatile uint8_t Planner::block_buffer_head, // Index of the next block to be pushed
Planner::block_buffer_tail;
float Planner::max_feedrate_mm_s[XYZE_N], // Max speeds in mm per second
Planner::axis_steps_per_mm[XYZE_N],
Planner::steps_to_mm[XYZE_N];
#if ENABLED(DISTINCT_E_FACTORS)
uint8_t Planner::last_extruder = 0; // Respond to extruder change
#endif
int16_t Planner::flow_percentage[EXTRUDERS] = ARRAY_BY_EXTRUDERS1(100); // Extrusion factor for each extruder
float Planner::e_factor[EXTRUDERS] = ARRAY_BY_EXTRUDERS1(1.0); // The flow percentage and volumetric multiplier combine to scale E movement
#if DISABLED(NO_VOLUMETRICS)
float Planner::filament_size[EXTRUDERS], // diameter of filament (in millimeters), typically around 1.75 or 2.85, 0 disables the volumetric calculations for the extruder
Planner::volumetric_area_nominal = CIRCLE_AREA((DEFAULT_NOMINAL_FILAMENT_DIA) * 0.5), // Nominal cross-sectional area
Planner::volumetric_multiplier[EXTRUDERS]; // Reciprocal of cross-sectional area of filament (in mm^2). Pre-calculated to reduce computation in the planner
#endif
uint32_t Planner::max_acceleration_steps_per_s2[XYZE_N],
Planner::max_acceleration_mm_per_s2[XYZE_N]; // Use M201 to override by software
uint32_t Planner::min_segment_time_us;
// Initialized by settings.load()
float Planner::min_feedrate_mm_s,
Planner::acceleration, // Normal acceleration mm/s^2 DEFAULT ACCELERATION for all printing moves. M204 SXXXX
Planner::retract_acceleration, // Retract acceleration mm/s^2 filament pull-back and push-forward while standing still in the other axes M204 TXXXX
Planner::travel_acceleration, // Travel acceleration mm/s^2 DEFAULT ACCELERATION for all NON printing moves. M204 MXXXX
Planner::max_jerk[XYZE], // The largest speed change requiring no acceleration
Planner::min_travel_feedrate_mm_s;
#if HAS_LEVELING
bool Planner::leveling_active = false; // Flag that auto bed leveling is enabled
#if ABL_PLANAR
matrix_3x3 Planner::bed_level_matrix; // Transform to compensate for bed level
#endif
#if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
float Planner::z_fade_height, // Initialized by settings.load()
Planner::inverse_z_fade_height,
Planner::last_fade_z;
#endif
#else
constexpr bool Planner::leveling_active;
#endif
#if ENABLED(SKEW_CORRECTION)
#if ENABLED(SKEW_CORRECTION_GCODE)
float Planner::xy_skew_factor;
#else
constexpr float Planner::xy_skew_factor;
#endif
#if ENABLED(SKEW_CORRECTION_FOR_Z) && ENABLED(SKEW_CORRECTION_GCODE)
float Planner::xz_skew_factor, Planner::yz_skew_factor;
#else
constexpr float Planner::xz_skew_factor, Planner::yz_skew_factor;
#endif
#endif
#if ENABLED(AUTOTEMP)
float Planner::autotemp_max = 250,
Planner::autotemp_min = 210,
Planner::autotemp_factor = 0.1;
bool Planner::autotemp_enabled = false;
#endif
// private:
int32_t Planner::position[NUM_AXIS] = { 0 };
uint32_t Planner::cutoff_long;
float Planner::previous_speed[NUM_AXIS],
Planner::previous_nominal_speed;
#if ENABLED(DISABLE_INACTIVE_EXTRUDER)
uint8_t Planner::g_uc_extruder_last_move[EXTRUDERS] = { 0 };
#endif
#ifdef XY_FREQUENCY_LIMIT
// Old direction bits. Used for speed calculations
unsigned char Planner::old_direction_bits = 0;
// Segment times (in µs). Used for speed calculations
uint32_t Planner::axis_segment_time_us[2][3] = { { MAX_FREQ_TIME_US + 1, 0, 0 }, { MAX_FREQ_TIME_US + 1, 0, 0 } };
#endif
#if ENABLED(LIN_ADVANCE)
float Planner::extruder_advance_K; // Initialized by settings.load()
#endif
#if HAS_POSITION_FLOAT
float Planner::position_float[XYZE]; // Needed for accurate maths. Steps cannot be used!
#endif
#if ENABLED(ULTRA_LCD)
volatile uint32_t Planner::block_buffer_runtime_us = 0;
#endif
/**
* Class and Instance Methods
*/
Planner::Planner() { init(); }
void Planner::init() {
ZERO(position);
#if HAS_POSITION_FLOAT
ZERO(position_float);
#endif
ZERO(previous_speed);
previous_nominal_speed = 0.0;
#if ABL_PLANAR
bed_level_matrix.set_to_identity();
#endif
clear_block_buffer();
}
#if ENABLED(BEZIER_JERK_CONTROL)
#ifdef __AVR__
// This routine, for AVR, returns 0x1000000 / d, but trying to get the inverse as
// fast as possible. A fast converging iterative Newton-Raphson method is able to
// reach full precision in just 1 iteration, and takes 211 cycles (worst case, mean
// case is less, up to 30 cycles for small divisors), instead of the 500 cycles a
// normal division would take.
//
// Inspired by the following page,
// https://stackoverflow.com/questions/27801397/newton-raphson-division-with-big-integers
//
// Suppose we want to calculate
// floor(2 ^ k / B) where B is a positive integer
// Then
// B must be <= 2^k, otherwise, the quotient is 0.
//
// The Newton - Raphson iteration for x = B / 2 ^ k yields:
// q[n + 1] = q[n] * (2 - q[n] * B / 2 ^ k)
//
// We can rearrange it as:
// q[n + 1] = q[n] * (2 ^ (k + 1) - q[n] * B) >> k
//
// Each iteration of this kind requires only integer multiplications
// and bit shifts.
// Does it converge to floor(2 ^ k / B) ?: Not necessarily, but, in
// the worst case, it eventually alternates between floor(2 ^ k / B)
// and ceiling(2 ^ k / B)).
// So we can use some not-so-clever test to see if we are in this
// case, and extract floor(2 ^ k / B).
// Lastly, a simple but important optimization for this approach is to
// truncate multiplications (i.e.calculate only the higher bits of the
// product) in the early iterations of the Newton - Raphson method.The
// reason to do so, is that the results of the early iterations are far
// from the quotient, and it doesn't matter to perform them inaccurately.
// Finally, we should pick a good starting value for x. Knowing how many
// digits the divisor has, we can estimate it:
//
// 2^k / x = 2 ^ log2(2^k / x)
// 2^k / x = 2 ^(log2(2^k)-log2(x))
// 2^k / x = 2 ^(k*log2(2)-log2(x))
// 2^k / x = 2 ^ (k-log2(x))
// 2^k / x >= 2 ^ (k-floor(log2(x)))
// floor(log2(x)) simply is the index of the most significant bit set.
//
// If we could improve this estimation even further, then the number of
// iterations can be dropped quite a bit, thus saving valuable execution time.
// The paper "Software Integer Division" by Thomas L.Rodeheffer, Microsoft
// Research, Silicon Valley,August 26, 2008, that is available at
// https://www.microsoft.com/en-us/research/wp-content/uploads/2008/08/tr-2008-141.pdf
// suggests , for its integer division algorithm, that using a table to supply the
// first 8 bits of precision, and due to the quadratic convergence nature of the
// Newton-Raphon iteration, then just 2 iterations should be enough to get
// maximum precision of the division.
// If we precompute values of inverses for small denominator values, then
// just one Newton-Raphson iteration is enough to reach full precision
// We will use the top 9 bits of the denominator as index.
//
// The AVR assembly function is implementing the following C code, included
// here as reference:
//
// uint32_t get_period_inverse(uint32_t d) {
// static const uint8_t inv_tab[256] = {
// 255,253,252,250,248,246,244,242,240,238,236,234,233,231,229,227,
// 225,224,222,220,218,217,215,213,212,210,208,207,205,203,202,200,
// 199,197,195,194,192,191,189,188,186,185,183,182,180,179,178,176,
// 175,173,172,170,169,168,166,165,164,162,161,160,158,157,156,154,
// 153,152,151,149,148,147,146,144,143,142,141,139,138,137,136,135,
// 134,132,131,130,129,128,127,126,125,123,122,121,120,119,118,117,
// 116,115,114,113,112,111,110,109,108,107,106,105,104,103,102,101,
// 100,99,98,97,96,95,94,93,92,91,90,89,88,88,87,86,
// 85,84,83,82,81,80,80,79,78,77,76,75,74,74,73,72,
// 71,70,70,69,68,67,66,66,65,64,63,62,62,61,60,59,
// 59,58,57,56,56,55,54,53,53,52,51,50,50,49,48,48,
// 47,46,46,45,44,43,43,42,41,41,40,39,39,38,37,37,
// 36,35,35,34,33,33,32,32,31,30,30,29,28,28,27,27,
// 26,25,25,24,24,23,22,22,21,21,20,19,19,18,18,17,
// 17,16,15,15,14,14,13,13,12,12,11,10,10,9,9,8,
// 8,7,7,6,6,5,5,4,4,3,3,2,2,1,0,0
// };
//
// // For small denominators, it is cheaper to directly store the result,
// // because those denominators would require 2 Newton-Raphson iterations
// // to converge to the required result precision. For bigger ones, just
// // ONE Newton-Raphson iteration is enough to get maximum precision!
// static const uint32_t small_inv_tab[111] PROGMEM = {
// 16777216,16777216,8388608,5592405,4194304,3355443,2796202,2396745,2097152,1864135,1677721,1525201,1398101,1290555,1198372,1118481,
// 1048576,986895,932067,883011,838860,798915,762600,729444,699050,671088,645277,621378,599186,578524,559240,541200,
// 524288,508400,493447,479349,466033,453438,441505,430185,419430,409200,399457,390167,381300,372827,364722,356962,
// 349525,342392,335544,328965,322638,316551,310689,305040,299593,294337,289262,284359,279620,275036,270600,266305,
// 262144,258111,254200,250406,246723,243148,239674,236298,233016,229824,226719,223696,220752,217885,215092,212369,
// 209715,207126,204600,202135,199728,197379,195083,192841,190650,188508,186413,184365,182361,180400,178481,176602,
// 174762,172960,171196,169466,167772,166111,164482,162885,161319,159783,158275,156796,155344,153919,152520
// };
//
// // For small divisors, it is best to directly retrieve the results
// if (d <= 110)
// return pgm_read_dword(&small_inv_tab[d]);
//
// // Compute initial estimation of 0x1000000/x -
// // Get most significant bit set on divider
// uint8_t idx = 0;
// uint32_t nr = d;
// if (!(nr & 0xFF0000)) {
// nr <<= 8;
// idx += 8;
// if (!(nr & 0xFF0000)) {
// nr <<= 8;
// idx += 8;
// }
// }
// if (!(nr & 0xF00000)) {
// nr <<= 4;
// idx += 4;
// }
// if (!(nr & 0xC00000)) {
// nr <<= 2;
// idx += 2;
// }
// if (!(nr & 0x800000)) {
// nr <<= 1;
// idx += 1;
// }
//
// // Isolate top 9 bits of the denominator, to be used as index into the initial estimation table
// uint32_t tidx = nr >> 15; // top 9 bits. bit8 is always set
// uint32_t ie = inv_tab[tidx & 0xFF] + 256; // Get the table value. bit9 is always set
// uint32_t x = idx <= 8 ? (ie >> (8 - idx)) : (ie << (idx - 8)); // Position the estimation at the proper place
//
// // Now, refine estimation by newton-raphson. 1 iteration is enough
// x = uint32_t((x * uint64_t((1 << 25) - x * d)) >> 24);
//
// // Estimate remainder
// uint32_t r = (1 << 24) - x * d;
//
// // Check if we must adjust result
// if (r >= d) x++;
//
// // x holds the proper estimation
// return uint32_t(x);
// }
//
static uint32_t get_period_inverse(uint32_t d) {
static const uint8_t inv_tab[256] PROGMEM = {
255,253,252,250,248,246,244,242,240,238,236,234,233,231,229,227,
225,224,222,220,218,217,215,213,212,210,208,207,205,203,202,200,
199,197,195,194,192,191,189,188,186,185,183,182,180,179,178,176,
175,173,172,170,169,168,166,165,164,162,161,160,158,157,156,154,
153,152,151,149,148,147,146,144,143,142,141,139,138,137,136,135,
134,132,131,130,129,128,127,126,125,123,122,121,120,119,118,117,
116,115,114,113,112,111,110,109,108,107,106,105,104,103,102,101,
100,99,98,97,96,95,94,93,92,91,90,89,88,88,87,86,
85,84,83,82,81,80,80,79,78,77,76,75,74,74,73,72,
71,70,70,69,68,67,66,66,65,64,63,62,62,61,60,59,
59,58,57,56,56,55,54,53,53,52,51,50,50,49,48,48,
47,46,46,45,44,43,43,42,41,41,40,39,39,38,37,37,
36,35,35,34,33,33,32,32,31,30,30,29,28,28,27,27,
26,25,25,24,24,23,22,22,21,21,20,19,19,18,18,17,
17,16,15,15,14,14,13,13,12,12,11,10,10,9,9,8,
8,7,7,6,6,5,5,4,4,3,3,2,2,1,0,0
};
// For small denominators, it is cheaper to directly store the result.
// For bigger ones, just ONE Newton-Raphson iteration is enough to get
// maximum precision we need
static const uint32_t small_inv_tab[111] PROGMEM = {
16777216,16777216,8388608,5592405,4194304,3355443,2796202,2396745,2097152,1864135,1677721,1525201,1398101,1290555,1198372,1118481,
1048576,986895,932067,883011,838860,798915,762600,729444,699050,671088,645277,621378,599186,578524,559240,541200,
524288,508400,493447,479349,466033,453438,441505,430185,419430,409200,399457,390167,381300,372827,364722,356962,
349525,342392,335544,328965,322638,316551,310689,305040,299593,294337,289262,284359,279620,275036,270600,266305,
262144,258111,254200,250406,246723,243148,239674,236298,233016,229824,226719,223696,220752,217885,215092,212369,
209715,207126,204600,202135,199728,197379,195083,192841,190650,188508,186413,184365,182361,180400,178481,176602,
174762,172960,171196,169466,167772,166111,164482,162885,161319,159783,158275,156796,155344,153919,152520
};
// For small divisors, it is best to directly retrieve the results
if (d <= 110)
return pgm_read_dword(&small_inv_tab[d]);
register uint8_t r8 = d & 0xFF;
register uint8_t r9 = (d >> 8) & 0xFF;
register uint8_t r10 = (d >> 16) & 0xFF;
register uint8_t r2,r3,r4,r5,r6,r7,r11,r12,r13,r14,r15,r16,r17,r18;
register const uint8_t* ptab = inv_tab;
__asm__ __volatile__(
// %8:%7:%6 = interval
// r31:r30: MUST be those registers, and they must point to the inv_tab
A("clr %13") // %13 = 0
// Now we must compute
// result = 0xFFFFFF / d
// %8:%7:%6 = interval
// %16:%15:%14 = nr
// %13 = 0
// A plain division of 24x24 bits should take 388 cycles to complete. We will
// use Newton-Raphson for the calculation, and will strive to get way less cycles
// for the same result - Using C division, it takes 500cycles to complete .
A("clr %3") // idx = 0
A("mov %14,%6")
A("mov %15,%7")
A("mov %16,%8") // nr = interval
A("tst %16") // nr & 0xFF0000 == 0 ?
A("brne 2f") // No, skip this
A("mov %16,%15")
A("mov %15,%14") // nr <<= 8, %14 not needed
A("subi %3,-8") // idx += 8
A("tst %16") // nr & 0xFF0000 == 0 ?
A("brne 2f") // No, skip this
A("mov %16,%15") // nr <<= 8, %14 not needed
A("clr %15") // We clear %14
A("subi %3,-8") // idx += 8
// here %16 != 0 and %16:%15 contains at least 9 MSBits, or both %16:%15 are 0
L("2")
A("cpi %16,0x10") // (nr & 0xF00000) == 0 ?
A("brcc 3f") // No, skip this
A("swap %15") // Swap nibbles
A("swap %16") // Swap nibbles. Low nibble is 0
A("mov %14, %15")
A("andi %14,0x0F") // Isolate low nibble
A("andi %15,0xF0") // Keep proper nibble in %15
A("or %16, %14") // %16:%15 <<= 4
A("subi %3,-4") // idx += 4
L("3")
A("cpi %16,0x40") // (nr & 0xC00000) == 0 ?
A("brcc 4f") // No, skip this
A("add %15,%15")
A("adc %16,%16")
A("add %15,%15")
A("adc %16,%16") // %16:%15 <<= 2
A("subi %3,-2") // idx += 2
L("4")
A("cpi %16,0x80") // (nr & 0x800000) == 0 ?
A("brcc 5f") // No, skip this
A("add %15,%15")
A("adc %16,%16") // %16:%15 <<= 1
A("inc %3") // idx += 1
// Now %16:%15 contains its MSBit set to 1, or %16:%15 is == 0. We are now absolutely sure
// we have at least 9 MSBits available to enter the initial estimation table
L("5")
A("add %15,%15")
A("adc %16,%16") // %16:%15 = tidx = (nr <<= 1), we lose the top MSBit (always set to 1, %16 is the index into the inverse table)
A("add r30,%16") // Only use top 8 bits
A("adc r31,%13") // r31:r30 = inv_tab + (tidx)
A("lpm %14, Z") // %14 = inv_tab[tidx]
A("ldi %15, 1") // %15 = 1 %15:%14 = inv_tab[tidx] + 256
// We must scale the approximation to the proper place
A("clr %16") // %16 will always be 0 here
A("subi %3,8") // idx == 8 ?
A("breq 6f") // yes, no need to scale
A("brcs 7f") // If C=1, means idx < 8, result was negative!
// idx > 8, now %3 = idx - 8. We must perform a left shift. idx range:[1-8]
A("sbrs %3,0") // shift by 1bit position?
A("rjmp 8f") // No
A("add %14,%14")
A("adc %15,%15") // %15:16 <<= 1
L("8")
A("sbrs %3,1") // shift by 2bit position?
A("rjmp 9f") // No
A("add %14,%14")
A("adc %15,%15")
A("add %14,%14")
A("adc %15,%15") // %15:16 <<= 1
L("9")
A("sbrs %3,2") // shift by 4bits position?
A("rjmp 16f") // No
A("swap %15") // Swap nibbles. lo nibble of %15 will always be 0
A("swap %14") // Swap nibbles
A("mov %12,%14")
A("andi %12,0x0F") // isolate low nibble
A("andi %14,0xF0") // and clear it
A("or %15,%12") // %15:%16 <<= 4
L("16")
A("sbrs %3,3") // shift by 8bits position?
A("rjmp 6f") // No, we are done
A("mov %16,%15")
A("mov %15,%14")
A("clr %14")
A("jmp 6f")
// idx < 8, now %3 = idx - 8. Get the count of bits
L("7")
A("neg %3") // %3 = -idx = count of bits to move right. idx range:[1...8]
A("sbrs %3,0") // shift by 1 bit position ?
A("rjmp 10f") // No, skip it
A("asr %15") // (bit7 is always 0 here)
A("ror %14")
L("10")
A("sbrs %3,1") // shift by 2 bit position ?
A("rjmp 11f") // No, skip it
A("asr %15") // (bit7 is always 0 here)
A("ror %14")
A("asr %15") // (bit7 is always 0 here)
A("ror %14")
L("11")
A("sbrs %3,2") // shift by 4 bit position ?
A("rjmp 12f") // No, skip it
A("swap %15") // Swap nibbles
A("andi %14, 0xF0") // Lose the lowest nibble
A("swap %14") // Swap nibbles. Upper nibble is 0
A("or %14,%15") // Pass nibble from upper byte
A("andi %15, 0x0F") // And get rid of that nibble
L("12")
A("sbrs %3,3") // shift by 8 bit position ?
A("rjmp 6f") // No, skip it
A("mov %14,%15")
A("clr %15")
L("6") // %16:%15:%14 = initial estimation of 0x1000000 / d
// Now, we must refine the estimation present on %16:%15:%14 using 1 iteration
// of Newton-Raphson. As it has a quadratic convergence, 1 iteration is enough
// to get more than 18bits of precision (the initial table lookup gives 9 bits of
// precision to start from). 18bits of precision is all what is needed here for result
// %8:%7:%6 = d = interval
// %16:%15:%14 = x = initial estimation of 0x1000000 / d
// %13 = 0
// %3:%2:%1:%0 = working accumulator
// Compute 1<<25 - x*d. Result should never exceed 25 bits and should always be positive
A("clr %0")
A("clr %1")
A("clr %2")
A("ldi %3,2") // %3:%2:%1:%0 = 0x2000000
A("mul %6,%14") // r1:r0 = LO(d) * LO(x)
A("sub %0,r0")
A("sbc %1,r1")
A("sbc %2,%13")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * LO(x)
A("mul %7,%14") // r1:r0 = MI(d) * LO(x)
A("sub %1,r0")
A("sbc %2,r1" )
A("sbc %3,%13") // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
A("mul %8,%14") // r1:r0 = HI(d) * LO(x)
A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
A("mul %6,%15") // r1:r0 = LO(d) * MI(x)
A("sub %1,r0")
A("sbc %2,r1")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
A("mul %7,%15") // r1:r0 = MI(d) * MI(x)
A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
A("mul %8,%15") // r1:r0 = HI(d) * MI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
A("mul %6,%16") // r1:r0 = LO(d) * HI(x)
A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
A("mul %7,%16") // r1:r0 = MI(d) * HI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MI(d) * HI(x) << 24
// %3:%2:%1:%0 = (1<<25) - x*d [169]
// We need to multiply that result by x, and we are only interested in the top 24bits of that multiply
// %16:%15:%14 = x = initial estimation of 0x1000000 / d
// %3:%2:%1:%0 = (1<<25) - x*d = acc
// %13 = 0
// result = %11:%10:%9:%5:%4
A("mul %14,%0") // r1:r0 = LO(x) * LO(acc)
A("mov %4,r1")
A("clr %5")
A("clr %9")
A("clr %10")
A("clr %11") // %11:%10:%9:%5:%4 = LO(x) * LO(acc) >> 8
A("mul %15,%0") // r1:r0 = MI(x) * LO(acc)
A("add %4,r0")
A("adc %5,r1")
A("adc %9,%13")
A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * LO(acc)
A("mul %16,%0") // r1:r0 = HI(x) * LO(acc)
A("add %5,r0")
A("adc %9,r1")
A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * LO(acc) << 8
A("mul %14,%1") // r1:r0 = LO(x) * MIL(acc)
A("add %4,r0")
A("adc %5,r1")
A("adc %9,%13")
A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * MIL(acc)
A("mul %15,%1") // r1:r0 = MI(x) * MIL(acc)
A("add %5,r0")
A("adc %9,r1")
A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 8
A("mul %16,%1") // r1:r0 = HI(x) * MIL(acc)
A("add %9,r0")
A("adc %10,r1")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 16
A("mul %14,%2") // r1:r0 = LO(x) * MIH(acc)
A("add %5,r0")
A("adc %9,r1")
A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * MIH(acc) << 8
A("mul %15,%2") // r1:r0 = MI(x) * MIH(acc)
A("add %9,r0")
A("adc %10,r1")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 16
A("mul %16,%2") // r1:r0 = HI(x) * MIH(acc)
A("add %10,r0")
A("adc %11,r1") // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 24
A("mul %14,%3") // r1:r0 = LO(x) * HI(acc)
A("add %9,r0")
A("adc %10,r1")
A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * HI(acc) << 16
A("mul %15,%3") // r1:r0 = MI(x) * HI(acc)
A("add %10,r0")
A("adc %11,r1") // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 24
A("mul %16,%3") // r1:r0 = HI(x) * HI(acc)
A("add %11,r0") // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 32
// At this point, %11:%10:%9 contains the new estimation of x.
// Finally, we must correct the result. Estimate remainder as
// (1<<24) - x*d
// %11:%10:%9 = x
// %8:%7:%6 = d = interval" "\n\t"
A("ldi %3,1")
A("clr %2")
A("clr %1")
A("clr %0") // %3:%2:%1:%0 = 0x1000000
A("mul %6,%9") // r1:r0 = LO(d) * LO(x)
A("sub %0,r0")
A("sbc %1,r1")
A("sbc %2,%13")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * LO(x)
A("mul %7,%9") // r1:r0 = MI(d) * LO(x)
A("sub %1,r0")
A("sbc %2,r1")
A("sbc %3,%13") // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
A("mul %8,%9") // r1:r0 = HI(d) * LO(x)
A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
A("mul %6,%10") // r1:r0 = LO(d) * MI(x)
A("sub %1,r0")
A("sbc %2,r1")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
A("mul %7,%10") // r1:r0 = MI(d) * MI(x)
A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
A("mul %8,%10") // r1:r0 = HI(d) * MI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
A("mul %6,%11") // r1:r0 = LO(d) * HI(x)
A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
A("mul %7,%11") // r1:r0 = MI(d) * HI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MI(d) * HI(x) << 24
// %3:%2:%1:%0 = r = (1<<24) - x*d
// %8:%7:%6 = d = interval
// Perform the final correction
A("sub %0,%6")
A("sbc %1,%7")
A("sbc %2,%8") // r -= d
A("brcs 14f") // if ( r >= d)
// %11:%10:%9 = x
A("ldi %3,1")
A("add %9,%3")
A("adc %10,%13")
A("adc %11,%13") // x++
L("14")
// Estimation is done. %11:%10:%9 = x
A("clr __zero_reg__") // Make C runtime happy
// [211 cycles total]
: "=r" (r2),
"=r" (r3),
"=r" (r4),
"=d" (r5),
"=r" (r6),
"=r" (r7),
"+r" (r8),
"+r" (r9),
"+r" (r10),
"=d" (r11),
"=r" (r12),
"=r" (r13),
"=d" (r14),
"=d" (r15),
"=d" (r16),
"=d" (r17),
"=d" (r18),
"+z" (ptab)
:
: "r0", "r1", "cc"
);
// Return the result
return r11 | (uint16_t(r12) << 8) | (uint32_t(r13) << 16);
}
#else
// All the other 32 CPUs can easily perform the inverse using hardware division,
// so we don´t need to reduce precision or to use assembly language at all.
// This routine, for all the other archs, returns 0x100000000 / d ~= 0xFFFFFFFF / d
static FORCE_INLINE uint32_t get_period_inverse(uint32_t d) {
return 0xFFFFFFFF / d;
}
#endif
#endif
#define MINIMAL_STEP_RATE 120
/**
* Calculate trapezoid parameters, multiplying the entry- and exit-speeds
* by the provided factors.
*/
void Planner::calculate_trapezoid_for_block(block_t* const block, const float &entry_factor, const float &exit_factor) {
uint32_t initial_rate = CEIL(block->nominal_rate * entry_factor),
final_rate = CEIL(block->nominal_rate * exit_factor); // (steps per second)
// Limit minimal step rate (Otherwise the timer will overflow.)
NOLESS(initial_rate, MINIMAL_STEP_RATE);
NOLESS(final_rate, MINIMAL_STEP_RATE);
#if ENABLED(BEZIER_JERK_CONTROL)
uint32_t cruise_rate = initial_rate;
#endif
const int32_t accel = block->acceleration_steps_per_s2;
// Steps required for acceleration, deceleration to/from nominal rate
int32_t accelerate_steps = CEIL(estimate_acceleration_distance(initial_rate, block->nominal_rate, accel)),
decelerate_steps = FLOOR(estimate_acceleration_distance(block->nominal_rate, final_rate, -accel)),
// Steps between acceleration and deceleration, if any
plateau_steps = block->step_event_count - accelerate_steps - decelerate_steps;
// Does accelerate_steps + decelerate_steps exceed step_event_count?
// Then we can't possibly reach the nominal rate, there will be no cruising.
// Use intersection_distance() to calculate accel / braking time in order to
// reach the final_rate exactly at the end of this block.
if (plateau_steps < 0) {
accelerate_steps = CEIL(intersection_distance(initial_rate, final_rate, accel, block->step_event_count));
NOLESS(accelerate_steps, 0); // Check limits due to numerical round-off
accelerate_steps = min((uint32_t)accelerate_steps, block->step_event_count);//(We can cast here to unsigned, because the above line ensures that we are above zero)
plateau_steps = 0;
#if ENABLED(BEZIER_JERK_CONTROL)
// We won't reach the cruising rate. Let's calculate the speed we will reach
cruise_rate = final_speed(initial_rate, accel, accelerate_steps);
#endif
}
#if ENABLED(BEZIER_JERK_CONTROL)
else // We have some plateau time, so the cruise rate will be the nominal rate
cruise_rate = block->nominal_rate;
#endif
// block->accelerate_until = accelerate_steps;
// block->decelerate_after = accelerate_steps+plateau_steps;
#if ENABLED(BEZIER_JERK_CONTROL)
// Jerk controlled speed requires to express speed versus time, NOT steps
uint32_t acceleration_time = ((float)(cruise_rate - initial_rate) / accel) * (HAL_STEPPER_TIMER_RATE),
deceleration_time = ((float)(cruise_rate - final_rate) / accel) * (HAL_STEPPER_TIMER_RATE);
// And to offload calculations from the ISR, we also calculate the inverse of those times here
uint32_t acceleration_time_inverse = get_period_inverse(acceleration_time);
uint32_t deceleration_time_inverse = get_period_inverse(deceleration_time);
#endif
CRITICAL_SECTION_START; // Fill variables used by the stepper in a critical section
if (!TEST(block->flag, BLOCK_BIT_BUSY)) { // Don't update variables if block is busy.
block->accelerate_until = accelerate_steps;
block->decelerate_after = accelerate_steps + plateau_steps;
block->initial_rate = initial_rate;
#if ENABLED(BEZIER_JERK_CONTROL)
block->acceleration_time = acceleration_time;
block->deceleration_time = deceleration_time;
block->acceleration_time_inverse = acceleration_time_inverse;
block->deceleration_time_inverse = deceleration_time_inverse;
block->cruise_rate = cruise_rate;
#endif
block->final_rate = final_rate;
}
CRITICAL_SECTION_END;
}
// "Junction jerk" in this context is the immediate change in speed at the junction of two blocks.
// This method will calculate the junction jerk as the euclidean distance between the nominal
// velocities of the respective blocks.
//inline float junction_jerk(block_t *before, block_t *after) {
// return SQRT(
// POW((before->speed_x-after->speed_x), 2)+POW((before->speed_y-after->speed_y), 2));
//}
// The kernel called by recalculate() when scanning the plan from last to first entry.
void Planner::reverse_pass_kernel(block_t* const current, const block_t* const next) {
if (current && next) {
// If entry speed is already at the maximum entry speed, no need to recheck. Block is cruising.
// If not, block in state of acceleration or deceleration. Reset entry speed to maximum and
// check for maximum allowable speed reductions to ensure maximum possible planned speed.
const float max_entry_speed = current->max_entry_speed;
if (current->entry_speed != max_entry_speed || TEST(next->flag, BLOCK_BIT_RECALCULATE)) {
// If nominal length true, max junction speed is guaranteed to be reached. Only compute
// for max allowable speed if block is decelerating and nominal length is false.
const float new_entry_speed = (TEST(current->flag, BLOCK_BIT_NOMINAL_LENGTH) || max_entry_speed <= next->entry_speed)
? max_entry_speed
: MIN(max_entry_speed, max_allowable_speed(-current->acceleration, next->entry_speed, current->millimeters));
if (new_entry_speed != current->entry_speed) {
current->entry_speed = new_entry_speed;
SBI(current->flag, BLOCK_BIT_RECALCULATE);
}
}
}
}
/**
* recalculate() needs to go over the current plan twice.
* Once in reverse and once forward. This implements the reverse pass.
*/
void Planner::reverse_pass() {
if (movesplanned() > 2) {
const uint8_t endnr = next_block_index(block_buffer_tail); // tail is running. tail+1 shouldn't be altered because it's connected to the running block.
uint8_t blocknr = prev_block_index(block_buffer_head);
block_t* current = &block_buffer[blocknr];
// Last/newest block in buffer:
const float max_entry_speed = current->max_entry_speed;
if (current->entry_speed != max_entry_speed) {
// If nominal length true, max junction speed is guaranteed to be reached. Only compute
// for max allowable speed if block is decelerating and nominal length is false.
const float new_entry_speed = TEST(current->flag, BLOCK_BIT_NOMINAL_LENGTH)
? max_entry_speed
: MIN(max_entry_speed, max_allowable_speed(-current->acceleration, MINIMUM_PLANNER_SPEED, current->millimeters));
if (current->entry_speed != new_entry_speed) {
current->entry_speed = new_entry_speed;
SBI(current->flag, BLOCK_BIT_RECALCULATE);
}
}
do {
const block_t * const next = current;
blocknr = prev_block_index(blocknr);
current = &block_buffer[blocknr];
reverse_pass_kernel(current, next);
} while (blocknr != endnr);
}
}
// The kernel called by recalculate() when scanning the plan from first to last entry.
void Planner::forward_pass_kernel(const block_t* const previous, block_t* const current) {
if (previous) {
// If the previous block is an acceleration block, too short to complete the full speed
// change, adjust the entry speed accordingly. Entry speeds have already been reset,
// maximized, and reverse-planned. If nominal length is set, max junction speed is
// guaranteed to be reached. No need to recheck.
if (!TEST(previous->flag, BLOCK_BIT_NOMINAL_LENGTH)) {
if (previous->entry_speed < current->entry_speed) {
const float new_entry_speed = MIN(current->entry_speed, max_allowable_speed(-previous->acceleration, previous->entry_speed, previous->millimeters));
// Check for junction speed change
if (current->entry_speed != new_entry_speed) {
current->entry_speed = new_entry_speed;
SBI(current->flag, BLOCK_BIT_RECALCULATE);
}
}
}
}
}
/**
* recalculate() needs to go over the current plan twice.
* Once in reverse and once forward. This implements the forward pass.
*/
void Planner::forward_pass() {
block_t* block[3] = { NULL, NULL, NULL };
for (uint8_t b = block_buffer_tail; b != block_buffer_head; b = next_block_index(b)) {
block[0] = block[1];
block[1] = block[2];
block[2] = &block_buffer[b];
forward_pass_kernel(block[0], block[1]);
}
forward_pass_kernel(block[1], block[2]);
}
/**
* Recalculate the trapezoid speed profiles for all blocks in the plan
* according to the entry_factor for each junction. Must be called by
* recalculate() after updating the blocks.
*/
void Planner::recalculate_trapezoids() {
int8_t block_index = block_buffer_tail;
block_t *current, *next = NULL;
while (block_index != block_buffer_head) {
current = next;
next = &block_buffer[block_index];
if (current) {
// Recalculate if current block entry or exit junction speed has changed.
if (TEST(current->flag, BLOCK_BIT_RECALCULATE) || TEST(next->flag, BLOCK_BIT_RECALCULATE)) {
// NOTE: Entry and exit factors always > 0 by all previous logic operations.
const float nomr = 1.0 / current->nominal_speed;
calculate_trapezoid_for_block(current, current->entry_speed * nomr, next->entry_speed * nomr);
#if ENABLED(LIN_ADVANCE)
if (current->use_advance_lead) {
const float comp = current->e_D_ratio * extruder_advance_K * axis_steps_per_mm[E_AXIS];
current->max_adv_steps = current->nominal_speed * comp;
current->final_adv_steps = next->entry_speed * comp;
}
#endif
CBI(current->flag, BLOCK_BIT_RECALCULATE); // Reset current only to ensure next trapezoid is computed
}
}
block_index = next_block_index(block_index);
}
// Last/newest block in buffer. Exit speed is set with MINIMUM_PLANNER_SPEED. Always recalculated.
if (next) {
const float nomr = 1.0 / next->nominal_speed;
calculate_trapezoid_for_block(next, next->entry_speed * nomr, (MINIMUM_PLANNER_SPEED) * nomr);
#if ENABLED(LIN_ADVANCE)
if (next->use_advance_lead) {
const float comp = next->e_D_ratio * extruder_advance_K * axis_steps_per_mm[E_AXIS];
next->max_adv_steps = next->nominal_speed * comp;
next->final_adv_steps = (MINIMUM_PLANNER_SPEED) * comp;
}
#endif
CBI(next->flag, BLOCK_BIT_RECALCULATE);
}
}
/**
* Recalculate the motion plan according to the following algorithm:
*
* 1. Go over every block in reverse order...
*
* Calculate a junction speed reduction (block_t.entry_factor) so:
*
* a. The junction jerk is within the set limit, and
*
* b. No speed reduction within one block requires faster
* deceleration than the one, true constant acceleration.
*
* 2. Go over every block in chronological order...
*
* Dial down junction speed reduction values if:
* a. The speed increase within one block would require faster
* acceleration than the one, true constant acceleration.
*
* After that, all blocks will have an entry_factor allowing all speed changes to
* be performed using only the one, true constant acceleration, and where no junction
* jerk is jerkier than the set limit, Jerky. Finally it will:
*
* 3. Recalculate "trapezoids" for all blocks.
*/
void Planner::recalculate() {
reverse_pass();
forward_pass();
recalculate_trapezoids();
}
#if ENABLED(AUTOTEMP)
void Planner::getHighESpeed() {
static float oldt = 0;
if (!autotemp_enabled) return;
if (thermalManager.degTargetHotend(0) + 2 < autotemp_min) return; // probably temperature set to zero.
float high = 0.0;
for (uint8_t b = block_buffer_tail; b != block_buffer_head; b = next_block_index(b)) {
block_t* block = &block_buffer[b];
if (block->steps[X_AXIS] || block->steps[Y_AXIS] || block->steps[Z_AXIS]) {
float se = (float)block->steps[E_AXIS] / block->step_event_count * block->nominal_speed; // mm/sec;
NOLESS(high, se);
}
}
float t = autotemp_min + high * autotemp_factor;
t = constrain(t, autotemp_min, autotemp_max);
if (t < oldt) t = t * (1 - (AUTOTEMP_OLDWEIGHT)) + oldt * (AUTOTEMP_OLDWEIGHT);
oldt = t;
thermalManager.setTargetHotend(t, 0);
}
#endif // AUTOTEMP
/**
* Maintain fans, paste extruder pressure,
*/
void Planner::check_axes_activity() {
unsigned char axis_active[NUM_AXIS] = { 0 },
tail_fan_speed[FAN_COUNT];
#if ENABLED(BARICUDA)
#if HAS_HEATER_1
uint8_t tail_valve_pressure;
#endif
#if HAS_HEATER_2
uint8_t tail_e_to_p_pressure;
#endif
#endif
if (has_blocks_queued()) {
#if FAN_COUNT > 0
for (uint8_t i = 0; i < FAN_COUNT; i++)
tail_fan_speed[i] = block_buffer[block_buffer_tail].fan_speed[i];
#endif
block_t* block;
#if ENABLED(BARICUDA)
block = &block_buffer[block_buffer_tail];
#if HAS_HEATER_1
tail_valve_pressure = block->valve_pressure;
#endif
#if HAS_HEATER_2
tail_e_to_p_pressure = block->e_to_p_pressure;
#endif
#endif
for (uint8_t b = block_buffer_tail; b != block_buffer_head; b = next_block_index(b)) {
block = &block_buffer[b];
LOOP_XYZE(i) if (block->steps[i]) axis_active[i]++;
}
}
else {
#if FAN_COUNT > 0
for (uint8_t i = 0; i < FAN_COUNT; i++) tail_fan_speed[i] = fanSpeeds[i];
#endif
#if ENABLED(BARICUDA)
#if HAS_HEATER_1
tail_valve_pressure = baricuda_valve_pressure;
#endif
#if HAS_HEATER_2
tail_e_to_p_pressure = baricuda_e_to_p_pressure;
#endif
#endif
}
#if ENABLED(DISABLE_X)
if (!axis_active[X_AXIS]) disable_X();
#endif
#if ENABLED(DISABLE_Y)
if (!axis_active[Y_AXIS]) disable_Y();
#endif
#if ENABLED(DISABLE_Z)
if (!axis_active[Z_AXIS]) disable_Z();
#endif
#if ENABLED(DISABLE_E)
if (!axis_active[E_AXIS]) disable_e_steppers();
#endif
#if FAN_COUNT > 0
#if FAN_KICKSTART_TIME > 0
static millis_t fan_kick_end[FAN_COUNT] = { 0 };
#define KICKSTART_FAN(f) \
if (tail_fan_speed[f]) { \
millis_t ms = millis(); \
if (fan_kick_end[f] == 0) { \
fan_kick_end[f] = ms + FAN_KICKSTART_TIME; \
tail_fan_speed[f] = 255; \
} else if (PENDING(ms, fan_kick_end[f])) \
tail_fan_speed[f] = 255; \
} else fan_kick_end[f] = 0
#if HAS_FAN0
KICKSTART_FAN(0);
#endif
#if HAS_FAN1
KICKSTART_FAN(1);
#endif
#if HAS_FAN2
KICKSTART_FAN(2);
#endif
#endif // FAN_KICKSTART_TIME > 0
#if FAN_MIN_PWM != 0 || FAN_MAX_PWM != 255
#define CALC_FAN_SPEED(f) (tail_fan_speed[f] ? map(tail_fan_speed[f], 1, 255, FAN_MIN_PWM, FAN_MAX_PWM) : 0)
#else
#define CALC_FAN_SPEED(f) tail_fan_speed[f]
#endif
#if ENABLED(FAN_SOFT_PWM)
#if HAS_FAN0
thermalManager.soft_pwm_amount_fan[0] = CALC_FAN_SPEED(0);
#endif
#if HAS_FAN1
thermalManager.soft_pwm_amount_fan[1] = CALC_FAN_SPEED(1);
#endif
#if HAS_FAN2
thermalManager.soft_pwm_amount_fan[2] = CALC_FAN_SPEED(2);
#endif
#else
#if HAS_FAN0
analogWrite(FAN_PIN, CALC_FAN_SPEED(0));
#endif
#if HAS_FAN1
analogWrite(FAN1_PIN, CALC_FAN_SPEED(1));
#endif
#if HAS_FAN2
analogWrite(FAN2_PIN, CALC_FAN_SPEED(2));
#endif
#endif
#endif // FAN_COUNT > 0
#if ENABLED(AUTOTEMP)
getHighESpeed();
#endif
#if ENABLED(BARICUDA)
#if HAS_HEATER_1
analogWrite(HEATER_1_PIN, tail_valve_pressure);
#endif
#if HAS_HEATER_2
analogWrite(HEATER_2_PIN, tail_e_to_p_pressure);
#endif
#endif
}
#if DISABLED(NO_VOLUMETRICS)
/**
* Get a volumetric multiplier from a filament diameter.
* This is the reciprocal of the circular cross-section area.
* Return 1.0 with volumetric off or a diameter of 0.0.
*/
inline float calculate_volumetric_multiplier(const float &diameter) {
return (parser.volumetric_enabled && diameter) ? 1.0 / CIRCLE_AREA(diameter * 0.5) : 1.0;
}
/**
* Convert the filament sizes into volumetric multipliers.
* The multiplier converts a given E value into a length.
*/
void Planner::calculate_volumetric_multipliers() {
for (uint8_t i = 0; i < COUNT(filament_size); i++) {
volumetric_multiplier[i] = calculate_volumetric_multiplier(filament_size[i]);
refresh_e_factor(i);
}
}
#endif // !NO_VOLUMETRICS
#if ENABLED(FILAMENT_WIDTH_SENSOR)
/**
* Convert the ratio value given by the filament width sensor
* into a volumetric multiplier. Conversion differs when using
* linear extrusion vs volumetric extrusion.
*/
void Planner::calculate_volumetric_for_width_sensor(const int8_t encoded_ratio) {
// Reconstitute the nominal/measured ratio
const float nom_meas_ratio = 1.0 + 0.01 * encoded_ratio,
ratio_2 = sq(nom_meas_ratio);
volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM] = parser.volumetric_enabled
? ratio_2 / CIRCLE_AREA(filament_width_nominal * 0.5) // Volumetric uses a true volumetric multiplier
: ratio_2; // Linear squares the ratio, which scales the volume
refresh_e_factor(FILAMENT_SENSOR_EXTRUDER_NUM);
}
#endif
#if PLANNER_LEVELING || HAS_UBL_AND_CURVES
/**
* rx, ry, rz - Cartesian positions in mm
* Leveled XYZ on completion
*/
void Planner::apply_leveling(float &rx, float &ry, float &rz) {
#if ENABLED(SKEW_CORRECTION)
skew(rx, ry, rz);
#endif
if (!leveling_active) return;
#if ABL_PLANAR
float dx = rx - (X_TILT_FULCRUM),
dy = ry - (Y_TILT_FULCRUM);
apply_rotation_xyz(bed_level_matrix, dx, dy, rz);
rx = dx + X_TILT_FULCRUM;
ry = dy + Y_TILT_FULCRUM;
#elif HAS_MESH
#if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
const float fade_scaling_factor = fade_scaling_factor_for_z(rz);
#else
constexpr float fade_scaling_factor = 1.0;
#endif
#if ENABLED(AUTO_BED_LEVELING_BILINEAR)
const float raw[XYZ] = { rx, ry, 0 };
#endif
rz += (
#if ENABLED(MESH_BED_LEVELING)
mbl.get_z(rx, ry
#if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
, fade_scaling_factor
#endif
)
#elif ENABLED(AUTO_BED_LEVELING_UBL)
fade_scaling_factor ? fade_scaling_factor * ubl.get_z_correction(rx, ry) : 0.0
#elif ENABLED(AUTO_BED_LEVELING_BILINEAR)
fade_scaling_factor ? fade_scaling_factor * bilinear_z_offset(raw) : 0.0
#endif
);
#endif
}
#endif
#if PLANNER_LEVELING
void Planner::unapply_leveling(float raw[XYZ]) {
if (leveling_active) {
#if ABL_PLANAR
matrix_3x3 inverse = matrix_3x3::transpose(bed_level_matrix);
float dx = raw[X_AXIS] - (X_TILT_FULCRUM),
dy = raw[Y_AXIS] - (Y_TILT_FULCRUM);
apply_rotation_xyz(inverse, dx, dy, raw[Z_AXIS]);
raw[X_AXIS] = dx + X_TILT_FULCRUM;
raw[Y_AXIS] = dy + Y_TILT_FULCRUM;
#elif HAS_MESH
#if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
const float fade_scaling_factor = fade_scaling_factor_for_z(raw[Z_AXIS]);
#else
constexpr float fade_scaling_factor = 1.0;
#endif
raw[Z_AXIS] -= (
#if ENABLED(MESH_BED_LEVELING)
mbl.get_z(raw[X_AXIS], raw[Y_AXIS]
#if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
, fade_scaling_factor
#endif
)
#elif ENABLED(AUTO_BED_LEVELING_UBL)
fade_scaling_factor ? fade_scaling_factor * ubl.get_z_correction(raw[X_AXIS], raw[Y_AXIS]) : 0.0
#elif ENABLED(AUTO_BED_LEVELING_BILINEAR)
fade_scaling_factor ? fade_scaling_factor * bilinear_z_offset(raw) : 0.0
#endif
);
#endif
}
#if ENABLED(SKEW_CORRECTION)
unskew(raw[X_AXIS], raw[Y_AXIS], raw[Z_AXIS]);
#endif
}
#endif // PLANNER_LEVELING
/**
* Get an axis position according to stepper position(s)
* For CORE machines apply translation from ABC to XYZ.
*/
float Planner::get_axis_position_mm(const AxisEnum axis) {
float axis_steps;
#if IS_CORE
// Requesting one of the "core" axes?
if (axis == CORE_AXIS_1 || axis == CORE_AXIS_2) {
// Protect the access to the position.
const bool was_enabled = STEPPER_ISR_ENABLED();
DISABLE_STEPPER_DRIVER_INTERRUPT();
// ((a1+a2)+(a1-a2))/2 -> (a1+a2+a1-a2)/2 -> (a1+a1)/2 -> a1
// ((a1+a2)-(a1-a2))/2 -> (a1+a2-a1+a2)/2 -> (a2+a2)/2 -> a2
axis_steps = 0.5f * (
axis == CORE_AXIS_2 ? CORESIGN(stepper.position(CORE_AXIS_1) - stepper.position(CORE_AXIS_2))
: stepper.position(CORE_AXIS_1) + stepper.position(CORE_AXIS_2)
);
if (was_enabled) ENABLE_STEPPER_DRIVER_INTERRUPT();
}
else
axis_steps = stepper.position(axis);
#else
axis_steps = stepper.position(axis);
#endif
return axis_steps * steps_to_mm[axis];
}
/**
* Block until all buffered steps are executed / cleaned
*/
void Planner::synchronize() { while (has_blocks_queued() || stepper.cleaning_buffer_counter) idle(); }
/**
* Planner::_buffer_steps
*
* Add a new linear movement to the buffer (in terms of steps).
*
* target - target position in steps units
* fr_mm_s - (target) speed of the move
* extruder - target extruder
*/
void Planner::_buffer_steps(const int32_t (&target)[XYZE]
#if HAS_POSITION_FLOAT
, const float (&target_float)[XYZE]
#endif
, float fr_mm_s, const uint8_t extruder, const float &millimeters/*=0.0*/
) {
const int32_t da = target[A_AXIS] - position[A_AXIS],
db = target[B_AXIS] - position[B_AXIS],
dc = target[C_AXIS] - position[C_AXIS];
int32_t de = target[E_AXIS] - position[E_AXIS];
/* <-- add a slash to enable
SERIAL_ECHOPAIR(" _buffer_steps FR:", fr_mm_s);
SERIAL_ECHOPAIR(" A:", target[A_AXIS]);
SERIAL_ECHOPAIR(" (", da);
SERIAL_ECHOPAIR(" steps) B:", target[B_AXIS]);
SERIAL_ECHOPAIR(" (", db);
SERIAL_ECHOPAIR(" steps) C:", target[C_AXIS]);
SERIAL_ECHOPAIR(" (", dc);
SERIAL_ECHOPAIR(" steps) E:", target[E_AXIS]);
SERIAL_ECHOPAIR(" (", de);
SERIAL_ECHOLNPGM(" steps)");
//*/
#if ENABLED(PREVENT_COLD_EXTRUSION) || ENABLED(PREVENT_LENGTHY_EXTRUDE)
if (de) {
#if ENABLED(PREVENT_COLD_EXTRUSION)
if (thermalManager.tooColdToExtrude(extruder)) {
position[E_AXIS] = target[E_AXIS]; // Behave as if the move really took place, but ignore E part
#if HAS_POSITION_FLOAT
position_float[E_AXIS] = target_float[E_AXIS];
#endif
de = 0; // no difference
SERIAL_ECHO_START();
SERIAL_ECHOLNPGM(MSG_ERR_COLD_EXTRUDE_STOP);
}
#endif // PREVENT_COLD_EXTRUSION
#if ENABLED(PREVENT_LENGTHY_EXTRUDE)
if (ABS(de * e_factor[extruder]) > (int32_t)axis_steps_per_mm[E_AXIS_N] * (EXTRUDE_MAXLENGTH)) { // It's not important to get max. extrusion length in a precision < 1mm, so save some cycles and cast to int
position[E_AXIS] = target[E_AXIS]; // Behave as if the move really took place, but ignore E part
#if HAS_POSITION_FLOAT
position_float[E_AXIS] = target_float[E_AXIS];
#endif
de = 0; // no difference
SERIAL_ECHO_START();
SERIAL_ECHOLNPGM(MSG_ERR_LONG_EXTRUDE_STOP);
}
#endif // PREVENT_LENGTHY_EXTRUDE
}
#endif // PREVENT_COLD_EXTRUSION || PREVENT_LENGTHY_EXTRUDE
// Compute direction bit-mask for this block
uint8_t dm = 0;
#if CORE_IS_XY
if (da < 0) SBI(dm, X_HEAD); // Save the real Extruder (head) direction in X Axis
if (db < 0) SBI(dm, Y_HEAD); // ...and Y
if (dc < 0) SBI(dm, Z_AXIS);
if (da + db < 0) SBI(dm, A_AXIS); // Motor A direction
if (CORESIGN(da - db) < 0) SBI(dm, B_AXIS); // Motor B direction
#elif CORE_IS_XZ
if (da < 0) SBI(dm, X_HEAD); // Save the real Extruder (head) direction in X Axis
if (db < 0) SBI(dm, Y_AXIS);
if (dc < 0) SBI(dm, Z_HEAD); // ...and Z
if (da + dc < 0) SBI(dm, A_AXIS); // Motor A direction
if (CORESIGN(da - dc) < 0) SBI(dm, C_AXIS); // Motor C direction
#elif CORE_IS_YZ
if (da < 0) SBI(dm, X_AXIS);
if (db < 0) SBI(dm, Y_HEAD); // Save the real Extruder (head) direction in Y Axis
if (dc < 0) SBI(dm, Z_HEAD); // ...and Z
if (db + dc < 0) SBI(dm, B_AXIS); // Motor B direction
if (CORESIGN(db - dc) < 0) SBI(dm, C_AXIS); // Motor C direction
#else
if (da < 0) SBI(dm, X_AXIS);
if (db < 0) SBI(dm, Y_AXIS);
if (dc < 0) SBI(dm, Z_AXIS);
#endif
if (de < 0) SBI(dm, E_AXIS);
const float esteps_float = de * e_factor[extruder];
const int32_t esteps = ABS(esteps_float) + 0.5;
// Wait for the next available block
uint8_t next_buffer_head;
block_t * const block = get_next_free_block(next_buffer_head);
// Clear all flags, including the "busy" bit
block->flag = 0x00;
// Set direction bits
block->direction_bits = dm;
// Number of steps for each axis
// See http://www.corexy.com/theory.html
#if CORE_IS_XY
block->steps[A_AXIS] = ABS(da + db);
block->steps[B_AXIS] = ABS(da - db);
block->steps[Z_AXIS] = ABS(dc);
#elif CORE_IS_XZ
block->steps[A_AXIS] = ABS(da + dc);
block->steps[Y_AXIS] = ABS(db);
block->steps[C_AXIS] = ABS(da - dc);
#elif CORE_IS_YZ
block->steps[X_AXIS] = ABS(da);
block->steps[B_AXIS] = ABS(db + dc);
block->steps[C_AXIS] = ABS(db - dc);
#elif IS_SCARA
block->steps[A_AXIS] = ABS(da);
block->steps[B_AXIS] = ABS(db);
block->steps[Z_AXIS] = ABS(dc);
#else
// default non-h-bot planning
block->steps[A_AXIS] = ABS(da);
block->steps[B_AXIS] = ABS(db);
block->steps[C_AXIS] = ABS(dc);
#endif
block->steps[E_AXIS] = esteps;
block->step_event_count = MAX4(block->steps[A_AXIS], block->steps[B_AXIS], block->steps[C_AXIS], esteps);
// Bail if this is a zero-length block
if (block->step_event_count < MIN_STEPS_PER_SEGMENT) return;
// For a mixing extruder, get a magnified step_event_count for each
#if ENABLED(MIXING_EXTRUDER)
for (uint8_t i = 0; i < MIXING_STEPPERS; i++)
block->mix_event_count[i] = mixing_factor[i] * block->step_event_count;
#endif
#if FAN_COUNT > 0
for (uint8_t i = 0; i < FAN_COUNT; i++) block->fan_speed[i] = fanSpeeds[i];
#endif
#if ENABLED(BARICUDA)
block->valve_pressure = baricuda_valve_pressure;
block->e_to_p_pressure = baricuda_e_to_p_pressure;
#endif
block->active_extruder = extruder;
#if ENABLED(AUTO_POWER_CONTROL)
if (block->steps[X_AXIS] || block->steps[Y_AXIS] || block->steps[Z_AXIS])
powerManager.power_on();
#endif
// Enable active axes
#if CORE_IS_XY
if (block->steps[A_AXIS] || block->steps[B_AXIS]) {
enable_X();
enable_Y();
}
#if DISABLED(Z_LATE_ENABLE)
if (block->steps[Z_AXIS]) enable_Z();
#endif
#elif CORE_IS_XZ
if (block->steps[A_AXIS] || block->steps[C_AXIS]) {
enable_X();
enable_Z();
}
if (block->steps[Y_AXIS]) enable_Y();
#elif CORE_IS_YZ
if (block->steps[B_AXIS] || block->steps[C_AXIS]) {
enable_Y();
enable_Z();
}
if (block->steps[X_AXIS]) enable_X();
#else
if (block->steps[X_AXIS]) enable_X();
if (block->steps[Y_AXIS]) enable_Y();
#if DISABLED(Z_LATE_ENABLE)
if (block->steps[Z_AXIS]) enable_Z();
#endif
#endif
// Enable extruder(s)
if (esteps) {
#if ENABLED(AUTO_POWER_CONTROL)
powerManager.power_on();
#endif
#if ENABLED(DISABLE_INACTIVE_EXTRUDER) // Enable only the selected extruder
#define DISABLE_IDLE_E(N) if (!g_uc_extruder_last_move[N]) disable_E##N();
for (uint8_t i = 0; i < EXTRUDERS; i++)
if (g_uc_extruder_last_move[i] > 0) g_uc_extruder_last_move[i]--;
switch (extruder) {
case 0:
#if EXTRUDERS > 1
DISABLE_IDLE_E(1);
#if EXTRUDERS > 2
DISABLE_IDLE_E(2);
#if EXTRUDERS > 3
DISABLE_IDLE_E(3);
#if EXTRUDERS > 4
DISABLE_IDLE_E(4);
#endif // EXTRUDERS > 4
#endif // EXTRUDERS > 3
#endif // EXTRUDERS > 2
#endif // EXTRUDERS > 1
enable_E0();
g_uc_extruder_last_move[0] = (BLOCK_BUFFER_SIZE) * 2;
#if ENABLED(DUAL_X_CARRIAGE) || ENABLED(DUAL_NOZZLE_DUPLICATION_MODE)
if (extruder_duplication_enabled) {
enable_E1();
g_uc_extruder_last_move[1] = (BLOCK_BUFFER_SIZE) * 2;
}
#endif
break;
#if EXTRUDERS > 1
case 1:
DISABLE_IDLE_E(0);
#if EXTRUDERS > 2
DISABLE_IDLE_E(2);
#if EXTRUDERS > 3
DISABLE_IDLE_E(3);
#if EXTRUDERS > 4
DISABLE_IDLE_E(4);
#endif // EXTRUDERS > 4
#endif // EXTRUDERS > 3
#endif // EXTRUDERS > 2
enable_E1();
g_uc_extruder_last_move[1] = (BLOCK_BUFFER_SIZE) * 2;
break;
#if EXTRUDERS > 2
case 2:
DISABLE_IDLE_E(0);
DISABLE_IDLE_E(1);
#if EXTRUDERS > 3
DISABLE_IDLE_E(3);
#if EXTRUDERS > 4
DISABLE_IDLE_E(4);
#endif
#endif
enable_E2();
g_uc_extruder_last_move[2] = (BLOCK_BUFFER_SIZE) * 2;
break;
#if EXTRUDERS > 3
case 3:
DISABLE_IDLE_E(0);
DISABLE_IDLE_E(1);
DISABLE_IDLE_E(2);
#if EXTRUDERS > 4
DISABLE_IDLE_E(4);
#endif
enable_E3();
g_uc_extruder_last_move[3] = (BLOCK_BUFFER_SIZE) * 2;
break;
#if EXTRUDERS > 4
case 4:
DISABLE_IDLE_E(0);
DISABLE_IDLE_E(1);
DISABLE_IDLE_E(2);
DISABLE_IDLE_E(3);
enable_E4();
g_uc_extruder_last_move[4] = (BLOCK_BUFFER_SIZE) * 2;
break;
#endif // EXTRUDERS > 4
#endif // EXTRUDERS > 3
#endif // EXTRUDERS > 2
#endif // EXTRUDERS > 1
}
#else
enable_E0();
enable_E1();
enable_E2();
enable_E3();
enable_E4();
#endif
}
if (esteps)
NOLESS(fr_mm_s, min_feedrate_mm_s);
else
NOLESS(fr_mm_s, min_travel_feedrate_mm_s);
/**
* This part of the code calculates the total length of the movement.
* For cartesian bots, the X_AXIS is the real X movement and same for Y_AXIS.
* But for corexy bots, that is not true. The "X_AXIS" and "Y_AXIS" motors (that should be named to A_AXIS
* and B_AXIS) cannot be used for X and Y length, because A=X+Y and B=X-Y.
* So we need to create other 2 "AXIS", named X_HEAD and Y_HEAD, meaning the real displacement of the Head.
* Having the real displacement of the head, we can calculate the total movement length and apply the desired speed.
*/
#if IS_CORE
float delta_mm[Z_HEAD + 1];
#if CORE_IS_XY
delta_mm[X_HEAD] = da * steps_to_mm[A_AXIS];
delta_mm[Y_HEAD] = db * steps_to_mm[B_AXIS];
delta_mm[Z_AXIS] = dc * steps_to_mm[Z_AXIS];
delta_mm[A_AXIS] = (da + db) * steps_to_mm[A_AXIS];
delta_mm[B_AXIS] = CORESIGN(da - db) * steps_to_mm[B_AXIS];
#elif CORE_IS_XZ
delta_mm[X_HEAD] = da * steps_to_mm[A_AXIS];
delta_mm[Y_AXIS] = db * steps_to_mm[Y_AXIS];
delta_mm[Z_HEAD] = dc * steps_to_mm[C_AXIS];
delta_mm[A_AXIS] = (da + dc) * steps_to_mm[A_AXIS];
delta_mm[C_AXIS] = CORESIGN(da - dc) * steps_to_mm[C_AXIS];
#elif CORE_IS_YZ
delta_mm[X_AXIS] = da * steps_to_mm[X_AXIS];
delta_mm[Y_HEAD] = db * steps_to_mm[B_AXIS];
delta_mm[Z_HEAD] = dc * steps_to_mm[C_AXIS];
delta_mm[B_AXIS] = (db + dc) * steps_to_mm[B_AXIS];
delta_mm[C_AXIS] = CORESIGN(db - dc) * steps_to_mm[C_AXIS];
#endif
#else
float delta_mm[ABCE];
delta_mm[A_AXIS] = da * steps_to_mm[A_AXIS];
delta_mm[B_AXIS] = db * steps_to_mm[B_AXIS];
delta_mm[C_AXIS] = dc * steps_to_mm[C_AXIS];
#endif
delta_mm[E_AXIS] = esteps_float * steps_to_mm[E_AXIS_N];
if (block->steps[A_AXIS] < MIN_STEPS_PER_SEGMENT && block->steps[B_AXIS] < MIN_STEPS_PER_SEGMENT && block->steps[C_AXIS] < MIN_STEPS_PER_SEGMENT) {
block->millimeters = ABS(delta_mm[E_AXIS]);
}
else if (!millimeters) {
block->millimeters = SQRT(
#if CORE_IS_XY
sq(delta_mm[X_HEAD]) + sq(delta_mm[Y_HEAD]) + sq(delta_mm[Z_AXIS])
#elif CORE_IS_XZ
sq(delta_mm[X_HEAD]) + sq(delta_mm[Y_AXIS]) + sq(delta_mm[Z_HEAD])
#elif CORE_IS_YZ
sq(delta_mm[X_AXIS]) + sq(delta_mm[Y_HEAD]) + sq(delta_mm[Z_HEAD])
#else
sq(delta_mm[X_AXIS]) + sq(delta_mm[Y_AXIS]) + sq(delta_mm[Z_AXIS])
#endif
);
}
else
block->millimeters = millimeters;
const float inverse_millimeters = 1.0 / block->millimeters; // Inverse millimeters to remove multiple divides
// Calculate inverse time for this move. No divide by zero due to previous checks.
// Example: At 120mm/s a 60mm move takes 0.5s. So this will give 2.0.
float inverse_secs = fr_mm_s * inverse_millimeters;
const uint8_t moves_queued = movesplanned();
// Slow down when the buffer starts to empty, rather than wait at the corner for a buffer refill
#if ENABLED(SLOWDOWN) || ENABLED(ULTRA_LCD) || defined(XY_FREQUENCY_LIMIT)
// Segment time im micro seconds
uint32_t segment_time_us = LROUND(1000000.0 / inverse_secs);
#endif
#if ENABLED(SLOWDOWN)
if (WITHIN(moves_queued, 2, (BLOCK_BUFFER_SIZE) / 2 - 1)) {
if (segment_time_us < min_segment_time_us) {
// buffer is draining, add extra time. The amount of time added increases if the buffer is still emptied more.
const uint32_t nst = segment_time_us + LROUND(2 * (min_segment_time_us - segment_time_us) / moves_queued);
inverse_secs = 1000000.0 / nst;
#if defined(XY_FREQUENCY_LIMIT) || ENABLED(ULTRA_LCD)
segment_time_us = nst;
#endif
}
}
#endif
#if ENABLED(ULTRA_LCD)
CRITICAL_SECTION_START
block_buffer_runtime_us += segment_time_us;
CRITICAL_SECTION_END
#endif
block->nominal_speed = block->millimeters * inverse_secs; // (mm/sec) Always > 0
block->nominal_rate = CEIL(block->step_event_count * inverse_secs); // (step/sec) Always > 0
#if ENABLED(FILAMENT_WIDTH_SENSOR)
static float filwidth_e_count = 0, filwidth_delay_dist = 0;
//FMM update ring buffer used for delay with filament measurements
if (extruder == FILAMENT_SENSOR_EXTRUDER_NUM && filwidth_delay_index[1] >= 0) { //only for extruder with filament sensor and if ring buffer is initialized
constexpr int MMD_CM = MAX_MEASUREMENT_DELAY + 1, MMD_MM = MMD_CM * 10;
// increment counters with next move in e axis
filwidth_e_count += delta_mm[E_AXIS];
filwidth_delay_dist += delta_mm[E_AXIS];
// Only get new measurements on forward E movement
if (!UNEAR_ZERO(filwidth_e_count)) {
// Loop the delay distance counter (modulus by the mm length)
while (filwidth_delay_dist >= MMD_MM) filwidth_delay_dist -= MMD_MM;
// Convert into an index into the measurement array
filwidth_delay_index[0] = int8_t(filwidth_delay_dist * 0.1);
// If the index has changed (must have gone forward)...
if (filwidth_delay_index[0] != filwidth_delay_index[1]) {
filwidth_e_count = 0; // Reset the E movement counter
const int8_t meas_sample = thermalManager.widthFil_to_size_ratio();
do {
filwidth_delay_index[1] = (filwidth_delay_index[1] + 1) % MMD_CM; // The next unused slot
measurement_delay[filwidth_delay_index[1]] = meas_sample; // Store the measurement
} while (filwidth_delay_index[0] != filwidth_delay_index[1]); // More slots to fill?
}
}
}
#endif
// Calculate and limit speed in mm/sec for each axis
float current_speed[NUM_AXIS], speed_factor = 1.0; // factor <1 decreases speed
LOOP_XYZE(i) {
const float cs = ABS((current_speed[i] = delta_mm[i] * inverse_secs));
#if ENABLED(DISTINCT_E_FACTORS)
if (i == E_AXIS) i += extruder;
#endif
if (cs > max_feedrate_mm_s[i]) NOMORE(speed_factor, max_feedrate_mm_s[i] / cs);
}
// Max segment time in µs.
#ifdef XY_FREQUENCY_LIMIT
// Check and limit the xy direction change frequency
const unsigned char direction_change = block->direction_bits ^ old_direction_bits;
old_direction_bits = block->direction_bits;
segment_time_us = LROUND((float)segment_time_us / speed_factor);
uint32_t xs0 = axis_segment_time_us[X_AXIS][0],
xs1 = axis_segment_time_us[X_AXIS][1],
xs2 = axis_segment_time_us[X_AXIS][2],
ys0 = axis_segment_time_us[Y_AXIS][0],
ys1 = axis_segment_time_us[Y_AXIS][1],
ys2 = axis_segment_time_us[Y_AXIS][2];
if (TEST(direction_change, X_AXIS)) {
xs2 = axis_segment_time_us[X_AXIS][2] = xs1;
xs1 = axis_segment_time_us[X_AXIS][1] = xs0;
xs0 = 0;
}
xs0 = axis_segment_time_us[X_AXIS][0] = xs0 + segment_time_us;
if (TEST(direction_change, Y_AXIS)) {
ys2 = axis_segment_time_us[Y_AXIS][2] = axis_segment_time_us[Y_AXIS][1];
ys1 = axis_segment_time_us[Y_AXIS][1] = axis_segment_time_us[Y_AXIS][0];
ys0 = 0;
}
ys0 = axis_segment_time_us[Y_AXIS][0] = ys0 + segment_time_us;
const uint32_t max_x_segment_time = MAX3(xs0, xs1, xs2),
max_y_segment_time = MAX3(ys0, ys1, ys2),
min_xy_segment_time = MIN(max_x_segment_time, max_y_segment_time);
if (min_xy_segment_time < MAX_FREQ_TIME_US) {
const float low_sf = speed_factor * min_xy_segment_time / (MAX_FREQ_TIME_US);
NOMORE(speed_factor, low_sf);
}
#endif // XY_FREQUENCY_LIMIT
// Correct the speed
if (speed_factor < 1.0) {
LOOP_XYZE(i) current_speed[i] *= speed_factor;
block->nominal_speed *= speed_factor;
block->nominal_rate *= speed_factor;
}
// Compute and limit the acceleration rate for the trapezoid generator.
const float steps_per_mm = block->step_event_count * inverse_millimeters;
uint32_t accel;
if (!block->steps[A_AXIS] && !block->steps[B_AXIS] && !block->steps[C_AXIS]) {
// convert to: acceleration steps/sec^2
accel = CEIL(retract_acceleration * steps_per_mm);
#if ENABLED(LIN_ADVANCE)
block->use_advance_lead = false;
#endif
}
else {
#define LIMIT_ACCEL_LONG(AXIS,INDX) do{ \
if (block->steps[AXIS] && max_acceleration_steps_per_s2[AXIS+INDX] < accel) { \
const uint32_t comp = max_acceleration_steps_per_s2[AXIS+INDX] * block->step_event_count; \
if (accel * block->steps[AXIS] > comp) accel = comp / block->steps[AXIS]; \
} \
}while(0)
#define LIMIT_ACCEL_FLOAT(AXIS,INDX) do{ \
if (block->steps[AXIS] && max_acceleration_steps_per_s2[AXIS+INDX] < accel) { \
const float comp = (float)max_acceleration_steps_per_s2[AXIS+INDX] * (float)block->step_event_count; \
if ((float)accel * (float)block->steps[AXIS] > comp) accel = comp / (float)block->steps[AXIS]; \
} \
}while(0)
// Start with print or travel acceleration
accel = CEIL((esteps ? acceleration : travel_acceleration) * steps_per_mm);
#if ENABLED(LIN_ADVANCE)
/**
*
* Use LIN_ADVANCE for blocks if all these are true:
*
* esteps : This is a print move, because we checked for A, B, C steps before.
*
* extruder_advance_K : There is an advance factor set.
*
* de > 0 : Extruder is running forward (e.g., for "Wipe while retracting" (Slic3r) or "Combing" (Cura) moves)
*/
block->use_advance_lead = esteps
&& extruder_advance_K
&& de > 0;
if (block->use_advance_lead) {
block->e_D_ratio = (target_float[E_AXIS] - position_float[E_AXIS]) /
#if IS_KINEMATIC
block->millimeters
#else
SQRT(sq(target_float[X_AXIS] - position_float[X_AXIS])
+ sq(target_float[Y_AXIS] - position_float[Y_AXIS])
+ sq(target_float[Z_AXIS] - position_float[Z_AXIS]))
#endif
;
// Check for unusual high e_D ratio to detect if a retract move was combined with the last print move due to min. steps per segment. Never execute this with advance!
// This assumes no one will use a retract length of 0mm < retr_length < ~0.2mm and no one will print 100mm wide lines using 3mm filament or 35mm wide lines using 1.75mm filament.
if (block->e_D_ratio > 3.0)
block->use_advance_lead = false;
else {
const uint32_t max_accel_steps_per_s2 = max_jerk[E_AXIS] / (extruder_advance_K * block->e_D_ratio) * steps_per_mm;
#if ENABLED(LA_DEBUG)
if (accel > max_accel_steps_per_s2)
SERIAL_ECHOLNPGM("Acceleration limited.");
#endif
NOMORE(accel, max_accel_steps_per_s2);
}
}
#endif
#if ENABLED(DISTINCT_E_FACTORS)
#define ACCEL_IDX extruder
#else
#define ACCEL_IDX 0
#endif
// Limit acceleration per axis
if (block->step_event_count <= cutoff_long) {
LIMIT_ACCEL_LONG(A_AXIS, 0);
LIMIT_ACCEL_LONG(B_AXIS, 0);
LIMIT_ACCEL_LONG(C_AXIS, 0);
LIMIT_ACCEL_LONG(E_AXIS, ACCEL_IDX);
}
else {
LIMIT_ACCEL_FLOAT(A_AXIS, 0);
LIMIT_ACCEL_FLOAT(B_AXIS, 0);
LIMIT_ACCEL_FLOAT(C_AXIS, 0);
LIMIT_ACCEL_FLOAT(E_AXIS, ACCEL_IDX);
}
}
block->acceleration_steps_per_s2 = accel;
block->acceleration = accel / steps_per_mm;
#if DISABLED(BEZIER_JERK_CONTROL)
block->acceleration_rate = (long)(accel * (4096.0 * 4096.0 / (HAL_STEPPER_TIMER_RATE)));
#endif
#if ENABLED(LIN_ADVANCE)
if (block->use_advance_lead) {
block->advance_speed = (HAL_STEPPER_TIMER_RATE) / (extruder_advance_K * block->e_D_ratio * block->acceleration * axis_steps_per_mm[E_AXIS_N]);
#if ENABLED(LA_DEBUG)
if (extruder_advance_K * block->e_D_ratio * block->acceleration * 2 < block->nominal_speed * block->e_D_ratio)
SERIAL_ECHOLNPGM("More than 2 steps per eISR loop executed.");
if (block->advance_speed < 200)
SERIAL_ECHOLNPGM("eISR running at > 10kHz.");
#endif
}
#endif
float vmax_junction; // Initial limit on the segment entry velocity
#if ENABLED(JUNCTION_DEVIATION)
/**
* Compute maximum allowable entry speed at junction by centripetal acceleration approximation.
* Let a circle be tangent to both previous and current path line segments, where the junction
* deviation is defined as the distance from the junction to the closest edge of the circle,
* colinear with the circle center. The circular segment joining the two paths represents the
* path of centripetal acceleration. Solve for max velocity based on max acceleration about the
* radius of the circle, defined indirectly by junction deviation. This may be also viewed as
* path width or max_jerk in the previous Grbl version. This approach does not actually deviate
* from path, but used as a robust way to compute cornering speeds, as it takes into account the
* nonlinearities of both the junction angle and junction velocity.
*
* NOTE: If the junction deviation value is finite, Grbl executes the motions in an exact path
* mode (G61). If the junction deviation value is zero, Grbl will execute the motion in an exact
* stop mode (G61.1) manner. In the future, if continuous mode (G64) is desired, the math here
* is exactly the same. Instead of motioning all the way to junction point, the machine will
* just follow the arc circle defined here. The Arduino doesn't have the CPU cycles to perform
* a continuous mode path, but ARM-based microcontrollers most certainly do.
*
* NOTE: The max junction speed is a fixed value, since machine acceleration limits cannot be
* changed dynamically during operation nor can the line move geometry. This must be kept in
* memory in the event of a feedrate override changing the nominal speeds of blocks, which can
* change the overall maximum entry speed conditions of all blocks.
*/
// Unit vector of previous path line segment
static float previous_unit_vec[
#if ENABLED(JUNCTION_DEVIATION_INCLUDE_E)
XYZE
#else
XYZ
#endif
];
float unit_vec[] = {
delta_mm[A_AXIS] * inverse_millimeters,
delta_mm[B_AXIS] * inverse_millimeters,
delta_mm[C_AXIS] * inverse_millimeters
#if ENABLED(JUNCTION_DEVIATION_INCLUDE_E)
, delta_mm[E_AXIS] * inverse_millimeters
#endif
};
// Skip first block or when previous_nominal_speed is used as a flag for homing and offset cycles.
if (moves_queued && !UNEAR_ZERO(previous_nominal_speed)) {
// Compute cosine of angle between previous and current path. (prev_unit_vec is negative)
// NOTE: Max junction velocity is computed without sin() or acos() by trig half angle identity.
float junction_cos_theta = -previous_unit_vec[X_AXIS] * unit_vec[X_AXIS]
-previous_unit_vec[Y_AXIS] * unit_vec[Y_AXIS]
-previous_unit_vec[Z_AXIS] * unit_vec[Z_AXIS]
#if ENABLED(JUNCTION_DEVIATION_INCLUDE_E)
-previous_unit_vec[E_AXIS] * unit_vec[E_AXIS]
#endif
;
// NOTE: Computed without any expensive trig, sin() or acos(), by trig half angle identity of cos(theta).
if (junction_cos_theta > 0.999999) {
// For a 0 degree acute junction, just set minimum junction speed.
vmax_junction = MINIMUM_PLANNER_SPEED;
}
else {
junction_cos_theta = MAX(junction_cos_theta, -0.999999); // Check for numerical round-off to avoid divide by zero.
const float sin_theta_d2 = SQRT(0.5 * (1.0 - junction_cos_theta)); // Trig half angle identity. Always positive.
// TODO: Technically, the acceleration used in calculation needs to be limited by the minimum of the
// two junctions. However, this shouldn't be a significant problem except in extreme circumstances.
vmax_junction = SQRT((block->acceleration * JUNCTION_DEVIATION_FACTOR * sin_theta_d2) / (1.0 - sin_theta_d2));
}
vmax_junction = MIN3(vmax_junction, block->nominal_speed, previous_nominal_speed);
}
else // Init entry speed to zero. Assume it starts from rest. Planner will correct this later.
vmax_junction = 0.0;
COPY(previous_unit_vec, unit_vec);
#else // Classic Jerk Limiting
/**
* Adapted from Průša MKS firmware
* https://github.com/prusa3d/Prusa-Firmware
*
* Start with a safe speed (from which the machine may halt to stop immediately).
*/
// Exit speed limited by a jerk to full halt of a previous last segment
static float previous_safe_speed;
float safe_speed = block->nominal_speed;
uint8_t limited = 0;
LOOP_XYZE(i) {
const float jerk = ABS(current_speed[i]), maxj = max_jerk[i];
if (jerk > maxj) {
if (limited) {
const float mjerk = maxj * block->nominal_speed;
if (jerk * safe_speed > mjerk) safe_speed = mjerk / jerk;
}
else {
++limited;
safe_speed = maxj;
}
}
}
if (moves_queued && !UNEAR_ZERO(previous_nominal_speed)) {
// Estimate a maximum velocity allowed at a joint of two successive segments.
// If this maximum velocity allowed is lower than the minimum of the entry / exit safe velocities,
// then the machine is not coasting anymore and the safe entry / exit velocities shall be used.
// The junction velocity will be shared between successive segments. Limit the junction velocity to their minimum.
// Pick the smaller of the nominal speeds. Higher speed shall not be achieved at the junction during coasting.
vmax_junction = MIN(block->nominal_speed, previous_nominal_speed);
// Factor to multiply the previous / current nominal velocities to get componentwise limited velocities.
float v_factor = 1;
limited = 0;
// Now limit the jerk in all axes.
const float smaller_speed_factor = vmax_junction / previous_nominal_speed;
LOOP_XYZE(axis) {
// Limit an axis. We have to differentiate: coasting, reversal of an axis, full stop.
float v_exit = previous_speed[axis] * smaller_speed_factor,
v_entry = current_speed[axis];
if (limited) {
v_exit *= v_factor;
v_entry *= v_factor;
}
// Calculate jerk depending on whether the axis is coasting in the same direction or reversing.
const float jerk = (v_exit > v_entry)
? // coasting axis reversal
( (v_entry > 0 || v_exit < 0) ? (v_exit - v_entry) : MAX(v_exit, -v_entry) )
: // v_exit <= v_entry coasting axis reversal
( (v_entry < 0 || v_exit > 0) ? (v_entry - v_exit) : MAX(-v_exit, v_entry) );
if (jerk > max_jerk[axis]) {
v_factor *= max_jerk[axis] / jerk;
++limited;
}
}
if (limited) vmax_junction *= v_factor;
// Now the transition velocity is known, which maximizes the shared exit / entry velocity while
// respecting the jerk factors, it may be possible, that applying separate safe exit / entry velocities will achieve faster prints.
const float vmax_junction_threshold = vmax_junction * 0.99f;
if (previous_safe_speed > vmax_junction_threshold && safe_speed > vmax_junction_threshold)
vmax_junction = safe_speed;
}
else
vmax_junction = safe_speed;
previous_safe_speed = safe_speed;
#endif // Classic Jerk Limiting
// Max entry speed of this block equals the max exit speed of the previous block.
block->max_entry_speed = vmax_junction;
// Initialize block entry speed. Compute based on deceleration to user-defined MINIMUM_PLANNER_SPEED.
const float v_allowable = max_allowable_speed(-block->acceleration, MINIMUM_PLANNER_SPEED, block->millimeters);
// If stepper ISR is disabled, this indicates buffer_segment wants to add a split block.
// In this case start with the max. allowed speed to avoid an interrupted first move.
block->entry_speed = STEPPER_ISR_ENABLED() ? MINIMUM_PLANNER_SPEED : MIN(vmax_junction, v_allowable);
// Initialize planner efficiency flags
// Set flag if block will always reach maximum junction speed regardless of entry/exit speeds.
// If a block can de/ac-celerate from nominal speed to zero within the length of the block, then
// the current block and next block junction speeds are guaranteed to always be at their maximum
// junction speeds in deceleration and acceleration, respectively. This is due to how the current
// block nominal speed limits both the current and next maximum junction speeds. Hence, in both
// the reverse and forward planners, the corresponding block junction speed will always be at the
// the maximum junction speed and may always be ignored for any speed reduction checks.
block->flag |= block->nominal_speed <= v_allowable ? BLOCK_FLAG_RECALCULATE | BLOCK_FLAG_NOMINAL_LENGTH : BLOCK_FLAG_RECALCULATE;
// Update previous path unit_vector and nominal speed
COPY(previous_speed, current_speed);
previous_nominal_speed = block->nominal_speed;
// Move buffer head
block_buffer_head = next_buffer_head;
// Update the position (only when a move was queued)
static_assert(COUNT(target) > 1, "Parameter to _buffer_steps must be (&target)[XYZE]!");
COPY(position, target);
#if HAS_POSITION_FLOAT
COPY(position_float, target_float);
#endif
recalculate();
} // _buffer_steps()
/**
* Planner::buffer_sync_block
* Add a block to the buffer that just updates the position
*/
void Planner::buffer_sync_block() {
// Wait for the next available block
uint8_t next_buffer_head;
block_t * const block = get_next_free_block(next_buffer_head);
block->flag = BLOCK_FLAG_SYNC_POSITION;
block->steps[A_AXIS] = position[A_AXIS];
block->steps[B_AXIS] = position[B_AXIS];
block->steps[C_AXIS] = position[C_AXIS];
block->steps[E_AXIS] = position[E_AXIS];
#if ENABLED(LIN_ADVANCE)
block->use_advance_lead = false;
#endif
block->nominal_speed =
block->entry_speed =
block->max_entry_speed =
block->millimeters =
block->acceleration = 0;
block->step_event_count =
block->nominal_rate =
block->initial_rate =
block->final_rate =
block->acceleration_steps_per_s2 =
block->segment_time_us = 0;
block_buffer_head = next_buffer_head;
stepper.wake_up();
} // buffer_sync_block()
/**
* Planner::buffer_segment
*
* Add a new linear movement to the buffer in axis units.
*
* Leveling and kinematics should be applied ahead of calling this.
*
* a,b,c,e - target positions in mm and/or degrees
* fr_mm_s - (target) speed of the move
* extruder - target extruder
* millimeters - the length of the movement, if known
*/
void Planner::buffer_segment(const float &a, const float &b, const float &c, const float &e, const float &fr_mm_s, const uint8_t extruder, const float &millimeters/*=0.0*/) {
// When changing extruders recalculate steps corresponding to the E position
#if ENABLED(DISTINCT_E_FACTORS)
if (last_extruder != extruder && axis_steps_per_mm[E_AXIS_N] != axis_steps_per_mm[E_AXIS + last_extruder]) {
position[E_AXIS] = LROUND(position[E_AXIS] * axis_steps_per_mm[E_AXIS_N] * steps_to_mm[E_AXIS + last_extruder]);
last_extruder = extruder;
}
#endif
// The target position of the tool in absolute steps
// Calculate target position in absolute steps
const int32_t target[ABCE] = {
LROUND(a * axis_steps_per_mm[A_AXIS]),
LROUND(b * axis_steps_per_mm[B_AXIS]),
LROUND(c * axis_steps_per_mm[C_AXIS]),
LROUND(e * axis_steps_per_mm[E_AXIS_N])
};
#if HAS_POSITION_FLOAT
const float target_float[XYZE] = { a, b, c, e };
#endif
// DRYRUN prevents E moves from taking place
if (DEBUGGING(DRYRUN)) {
position[E_AXIS] = target[E_AXIS];
#if HAS_POSITION_FLOAT
position_float[E_AXIS] = e;
#endif
}
/* <-- add a slash to enable
SERIAL_ECHOPAIR(" buffer_segment FR:", fr_mm_s);
#if IS_KINEMATIC
SERIAL_ECHOPAIR(" A:", a);
SERIAL_ECHOPAIR(" (", position[A_AXIS]);
SERIAL_ECHOPAIR("->", target[A_AXIS]);
SERIAL_ECHOPAIR(") B:", b);
#else
SERIAL_ECHOPAIR(" X:", a);
SERIAL_ECHOPAIR(" (", position[X_AXIS]);
SERIAL_ECHOPAIR("->", target[X_AXIS]);
SERIAL_ECHOPAIR(") Y:", b);
#endif
SERIAL_ECHOPAIR(" (", position[Y_AXIS]);
SERIAL_ECHOPAIR("->", target[Y_AXIS]);
#if ENABLED(DELTA)
SERIAL_ECHOPAIR(") C:", c);
#else
SERIAL_ECHOPAIR(") Z:", c);
#endif
SERIAL_ECHOPAIR(" (", position[Z_AXIS]);
SERIAL_ECHOPAIR("->", target[Z_AXIS]);
SERIAL_ECHOPAIR(") E:", e);
SERIAL_ECHOPAIR(" (", position[E_AXIS]);
SERIAL_ECHOPAIR("->", target[E_AXIS]);
SERIAL_ECHOLNPGM(")");
//*/
// Always split the first move into two (if not homing or probing)
if (!has_blocks_queued()) {
#define _BETWEEN(A) (position[_AXIS(A)] + target[_AXIS(A)]) >> 1
const int32_t between[ABCE] = { _BETWEEN(A), _BETWEEN(B), _BETWEEN(C), _BETWEEN(E) };
#if HAS_POSITION_FLOAT
#define _BETWEEN_F(A) (position_float[_AXIS(A)] + target_float[_AXIS(A)]) * 0.5
const float between_float[ABCE] = { _BETWEEN_F(A), _BETWEEN_F(B), _BETWEEN_F(C), _BETWEEN_F(E) };
#endif
DISABLE_STEPPER_DRIVER_INTERRUPT();
_buffer_steps(between
#if HAS_POSITION_FLOAT
, between_float
#endif
, fr_mm_s, extruder, millimeters * 0.5
);
const uint8_t next = block_buffer_head;
_buffer_steps(target
#if HAS_POSITION_FLOAT
, target_float
#endif
, fr_mm_s, extruder, millimeters * 0.5
);
SBI(block_buffer[next].flag, BLOCK_BIT_CONTINUED);
ENABLE_STEPPER_DRIVER_INTERRUPT();
}
else
_buffer_steps(target
#if HAS_POSITION_FLOAT
, target_float
#endif
, fr_mm_s, extruder, millimeters
);
stepper.wake_up();
} // buffer_segment()
/**
* Directly set the planner XYZ position (and stepper positions)
* converting mm (or angles for SCARA) into steps.
*
* On CORE machines stepper ABC will be translated from the given XYZ.
*/
void Planner::_set_position_mm(const float &a, const float &b, const float &c, const float &e) {
#if ENABLED(DISTINCT_E_FACTORS)
#define _EINDEX (E_AXIS + active_extruder)
last_extruder = active_extruder;
#else
#define _EINDEX E_AXIS
#endif
position[A_AXIS] = LROUND(a * axis_steps_per_mm[A_AXIS]),
position[B_AXIS] = LROUND(b * axis_steps_per_mm[B_AXIS]),
position[C_AXIS] = LROUND(c * axis_steps_per_mm[C_AXIS]),
position[E_AXIS] = LROUND(e * axis_steps_per_mm[_EINDEX]);
#if HAS_POSITION_FLOAT
position_float[A_AXIS] = a;
position_float[B_AXIS] = b;
position_float[C_AXIS] = c;
position_float[E_AXIS] = e;
#endif
previous_nominal_speed = 0.0; // Resets planner junction speeds. Assumes start from rest.
ZERO(previous_speed);
buffer_sync_block();
}
void Planner::set_position_mm_kinematic(const float (&cart)[XYZE]) {
#if PLANNER_LEVELING
float raw[XYZ] = { cart[X_AXIS], cart[Y_AXIS], cart[Z_AXIS] };
apply_leveling(raw);
#else
const float (&raw)[XYZE] = cart;
#endif
#if IS_KINEMATIC
inverse_kinematics(raw);
_set_position_mm(delta[A_AXIS], delta[B_AXIS], delta[C_AXIS], cart[E_AXIS]);
#else
_set_position_mm(raw[X_AXIS], raw[Y_AXIS], raw[Z_AXIS], cart[E_AXIS]);
#endif
}
/**
* Sync from the stepper positions. (e.g., after an interrupted move)
*/
void Planner::sync_from_steppers() {
LOOP_XYZE(i) {
position[i] = stepper.position((AxisEnum)i);
#if HAS_POSITION_FLOAT
position_float[i] = position[i] * steps_to_mm[i
#if ENABLED(DISTINCT_E_FACTORS)
+ (i == E_AXIS ? active_extruder : 0)
#endif
];
#endif
}
}
/**
* Setters for planner position (also setting stepper position).
*/
void Planner::set_position_mm(const AxisEnum axis, const float &v) {
#if ENABLED(DISTINCT_E_FACTORS)
const uint8_t axis_index = axis + (axis == E_AXIS ? active_extruder : 0);
last_extruder = active_extruder;
#else
const uint8_t axis_index = axis;
#endif
position[axis] = LROUND(v * axis_steps_per_mm[axis_index]);
#if HAS_POSITION_FLOAT
position_float[axis] = v;
#endif
previous_speed[axis] = 0.0;
buffer_sync_block();
}
// Recalculate the steps/s^2 acceleration rates, based on the mm/s^2
void Planner::reset_acceleration_rates() {
#if ENABLED(DISTINCT_E_FACTORS)
#define AXIS_CONDITION (i < E_AXIS || i == E_AXIS + active_extruder)
#else
#define AXIS_CONDITION true
#endif
uint32_t highest_rate = 1;
LOOP_XYZE_N(i) {
max_acceleration_steps_per_s2[i] = max_acceleration_mm_per_s2[i] * axis_steps_per_mm[i];
if (AXIS_CONDITION) NOLESS(highest_rate, max_acceleration_steps_per_s2[i]);
}
cutoff_long = 4294967295UL / highest_rate; // 0xFFFFFFFFUL
}
// Recalculate position, steps_to_mm if axis_steps_per_mm changes!
void Planner::refresh_positioning() {
LOOP_XYZE_N(i) steps_to_mm[i] = 1.0 / axis_steps_per_mm[i];
set_position_mm_kinematic(current_position);
reset_acceleration_rates();
}
#if ENABLED(AUTOTEMP)
void Planner::autotemp_M104_M109() {
if ((autotemp_enabled = parser.seen('F'))) autotemp_factor = parser.value_float();
if (parser.seen('S')) autotemp_min = parser.value_celsius();
if (parser.seen('B')) autotemp_max = parser.value_celsius();
}
#endif