From 7ee1ab4fd3be0e6e054815e619344dd4ce47b1fa Mon Sep 17 00:00:00 2001 From: Scott Lahteine Date: Tue, 8 May 2018 03:42:45 -0500 Subject: [PATCH] =?UTF-8?q?Add=20B=C3=A9zier=20Jerk=20Control=20option?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .travis.yml | 2 +- Marlin/Configuration.h | 11 + Marlin/macros.h | 3 + Marlin/planner.cpp | 545 +++++++++++++++++++++++- Marlin/planner.h | 34 +- Marlin/stepper.cpp | 922 ++++++++++++++++++++++++++++++++++++++--- Marlin/stepper.h | 82 ++-- 7 files changed, 1486 insertions(+), 113 deletions(-) diff --git a/.travis.yml b/.travis.yml index 4ca3b13ab8..568f9c6cd2 100644 --- a/.travis.yml +++ b/.travis.yml @@ -118,7 +118,7 @@ script: # Add a Sled Z Probe, use UBL Cartesian moves, use Japanese language # - opt_set LANGUAGE kana_utf8 - - opt_enable Z_PROBE_SLED SKEW_CORRECTION SKEW_CORRECTION_FOR_Z SKEW_CORRECTION_GCODE + - opt_enable Z_PROBE_SLED SKEW_CORRECTION SKEW_CORRECTION_FOR_Z SKEW_CORRECTION_GCODE BEZIER_JERK_CONTROL - opt_disable SEGMENT_LEVELED_MOVES - opt_enable_adv BABYSTEP_ZPROBE_OFFSET DOUBLECLICK_FOR_Z_BABYSTEPPING - build_marlin diff --git a/Marlin/Configuration.h b/Marlin/Configuration.h index 1a416dd6f2..7d0efcc303 100644 --- a/Marlin/Configuration.h +++ b/Marlin/Configuration.h @@ -594,6 +594,17 @@ #define DEFAULT_ZJERK 0.3 #define DEFAULT_EJERK 5.0 +/** + * Realtime Jerk Control + * + * This option eliminates vibration during printing by fitting a Bézier + * curve to move acceleration, producing much smoother direction changes. + * Because this is computationally-intensive, a 32-bit MCU is required. + * + * See https://github.com/synthetos/TinyG/wiki/Jerk-Controlled-Motion-Explained + */ +//#define BEZIER_JERK_CONTROL + //=========================================================================== //============================= Z Probe Options ============================= //=========================================================================== diff --git a/Marlin/macros.h b/Marlin/macros.h index a5f92a2d9f..74dd68ec6b 100644 --- a/Marlin/macros.h +++ b/Marlin/macros.h @@ -117,6 +117,9 @@ #define STRINGIFY_(M) #M #define STRINGIFY(M) STRINGIFY_(M) +#define A(CODE) " " CODE "\n\t" +#define L(CODE) CODE ":\n\t" + // Macros for bit masks #undef _BV #define _BV(b) (1<<(b)) diff --git a/Marlin/planner.cpp b/Marlin/planner.cpp index 7a05ccc493..21f7cdd475 100644 --- a/Marlin/planner.cpp +++ b/Marlin/planner.cpp @@ -204,6 +204,514 @@ void Planner::init() { clear_block_buffer(); } +#if ENABLED(BEZIER_JERK_CONTROL) + + // 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); + } + +#endif // BEZIER_JERK_CONTROL + #define MINIMAL_STEP_RATE 120 /** @@ -218,6 +726,10 @@ void Planner::calculate_trapezoid_for_block(block_t* const block, const float &e 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 @@ -235,16 +747,43 @@ void Planner::calculate_trapezoid_for_block(block_t* const block, const float &e 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; @@ -1286,10 +1825,12 @@ void Planner::_buffer_steps(const int32_t (&target)[XYZE] } block->acceleration_steps_per_s2 = accel; block->acceleration = accel / steps_per_mm; - block->acceleration_rate = (long)(accel * 16777216.0 / ((F_CPU) * 0.125)); // * 8.388608 + #if DISABLED(BEZIER_JERK_CONTROL) + block->acceleration_rate = (long)(accel * (4096.0 * 4096.0 / (HAL_STEPPER_TIMER_RATE))); // * 8.388608 + #endif #if ENABLED(LIN_ADVANCE) if (block->use_advance_lead) { - block->advance_speed = ((F_CPU) * 0.125) / (extruder_advance_K * block->e_D_ratio * block->acceleration * axis_steps_per_mm[E_AXIS]); + block->advance_speed = (HAL_STEPPER_TIMER_RATE) / (extruder_advance_K * block->e_D_ratio * block->acceleration * axis_steps_per_mm[E_AXIS]); #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."); diff --git a/Marlin/planner.h b/Marlin/planner.h index e051c4a0dc..79e2c2ee33 100644 --- a/Marlin/planner.h +++ b/Marlin/planner.h @@ -90,9 +90,24 @@ typedef struct { uint32_t mix_event_count[MIXING_STEPPERS]; // Scaled step_event_count for the mixing steppers #endif + // Settings for the trapezoid generator int32_t accelerate_until, // The index of the step event on which to stop acceleration - decelerate_after, // The index of the step event on which to start decelerating - acceleration_rate; // The acceleration rate used for acceleration calculation + decelerate_after; // The index of the step event on which to start decelerating + + uint32_t nominal_rate, // The nominal step rate for this block in step_events/sec + initial_rate, // The jerk-adjusted step rate at start of block + final_rate, // The minimal rate at exit + acceleration_steps_per_s2; // acceleration steps/sec^2 + + #if ENABLED(BEZIER_JERK_CONTROL) + uint32_t cruise_rate; // The actual cruise rate to use, between end of the acceleration phase and start of deceleration phase + uint32_t acceleration_time, // Acceleration time and deceleration time in STEP timer counts + deceleration_time; + uint32_t acceleration_time_inverse, // Inverse of acceleration and deceleration periods, expressed as integer. Scale depends on CPU being used + deceleration_time_inverse; + #else + int32_t acceleration_rate; // The acceleration rate used for acceleration calculation + #endif uint8_t direction_bits; // The direction bit set for this block (refers to *_DIRECTION_BIT in config.h) @@ -112,12 +127,6 @@ typedef struct { millimeters, // The total travel of this block in mm acceleration; // acceleration mm/sec^2 - // Settings for the trapezoid generator - uint32_t nominal_rate, // The nominal step rate for this block in step_events/sec - initial_rate, // The jerk-adjusted step rate at start of block - final_rate, // The minimal rate at exit - acceleration_steps_per_s2; // acceleration steps/sec^2 - #if FAN_COUNT > 0 uint16_t fan_speed[FAN_COUNT]; #endif @@ -661,6 +670,15 @@ class Planner { return SQRT(sq(target_velocity) - 2 * accel * distance); } + #if ENABLED(BEZIER_JERK_CONTROL) + /** + * Calculate the speed reached given initial speed, acceleration and distance + */ + static float final_speed(const float &initial_velocity, const float &accel, const float &distance) { + return SQRT(sq(initial_velocity) + 2 * accel * distance); + } + #endif + static void calculate_trapezoid_for_block(block_t* const block, const float &entry_factor, const float &exit_factor); static void reverse_pass_kernel(block_t* const current, const block_t * const next); diff --git a/Marlin/stepper.cpp b/Marlin/stepper.cpp index 06dc29dc18..1f03e3ccb3 100644 --- a/Marlin/stepper.cpp +++ b/Marlin/stepper.cpp @@ -41,8 +41,16 @@ * along with Grbl. If not, see . */ -/* The timer calculations of this module informed by the 'RepRap cartesian firmware' by Zack Smith - and Philipp Tiefenbacher. */ +/** + * Timer calculations informed by the 'RepRap cartesian firmware' by Zack Smith + * and Philipp Tiefenbacher. + */ + +/** + * Jerk controlled movements planner added Apr 2018 by Eduardo José Tagle. + * Equations based on Synthethos TinyG2 sources, but the fixed-point + * implementation is new, as we are running the ISR with a variable period. + */ #include "Marlin.h" #include "stepper.h" @@ -98,6 +106,16 @@ int32_t Stepper::counter_X = 0, volatile uint32_t Stepper::step_events_completed = 0; // The number of step events executed in the current block +#if ENABLED(BEZIER_JERK_CONTROL) + int32_t __attribute__((used)) Stepper::bezier_A __asm__("bezier_A"); // A coefficient in Bézier speed curve with alias for assembler + int32_t __attribute__((used)) Stepper::bezier_B __asm__("bezier_B"); // B coefficient in Bézier speed curve with alias for assembler + int32_t __attribute__((used)) Stepper::bezier_C __asm__("bezier_C"); // C coefficient in Bézier speed curve with alias for assembler + uint32_t __attribute__((used)) Stepper::bezier_F __asm__("bezier_F"); // F coefficient in Bézier speed curve with alias for assembler + uint32_t __attribute__((used)) Stepper::bezier_AV __asm__("bezier_AV"); // AV coefficient in Bézier speed curve with alias for assembler + bool __attribute__((used)) Stepper::A_negative __asm__("A_negative"); // If A coefficient was negative + bool Stepper::bezier_2nd_half; // =false If Bézier curve has been initialized or not +#endif + #if ENABLED(LIN_ADVANCE) uint32_t Stepper::LA_decelerate_after; @@ -134,8 +152,10 @@ volatile signed char Stepper::count_direction[NUM_AXIS] = { 1, 1, 1, 1 }; uint8_t Stepper::step_loops, Stepper::step_loops_nominal; -uint16_t Stepper::OCR1A_nominal, - Stepper::acc_step_rate; // needed for deceleration start point +uint16_t Stepper::OCR1A_nominal; +#if DISABLED(BEZIER_JERK_CONTROL) + uint16_t Stepper::acc_step_rate; // needed for deceleration start point +#endif volatile int32_t Stepper::endstops_trigsteps[XYZ]; @@ -232,41 +252,41 @@ volatile int32_t Stepper::endstops_trigsteps[XYZ]; // #define MultiU24X32toH16(intRes, longIn1, longIn2) \ asm volatile ( \ - "clr r26 \n\t" \ - "mul %A1, %B2 \n\t" \ - "mov r27, r1 \n\t" \ - "mul %B1, %C2 \n\t" \ - "movw %A0, r0 \n\t" \ - "mul %C1, %C2 \n\t" \ - "add %B0, r0 \n\t" \ - "mul %C1, %B2 \n\t" \ - "add %A0, r0 \n\t" \ - "adc %B0, r1 \n\t" \ - "mul %A1, %C2 \n\t" \ - "add r27, r0 \n\t" \ - "adc %A0, r1 \n\t" \ - "adc %B0, r26 \n\t" \ - "mul %B1, %B2 \n\t" \ - "add r27, r0 \n\t" \ - "adc %A0, r1 \n\t" \ - "adc %B0, r26 \n\t" \ - "mul %C1, %A2 \n\t" \ - "add r27, r0 \n\t" \ - "adc %A0, r1 \n\t" \ - "adc %B0, r26 \n\t" \ - "mul %B1, %A2 \n\t" \ - "add r27, r1 \n\t" \ - "adc %A0, r26 \n\t" \ - "adc %B0, r26 \n\t" \ - "lsr r27 \n\t" \ - "adc %A0, r26 \n\t" \ - "adc %B0, r26 \n\t" \ - "mul %D2, %A1 \n\t" \ - "add %A0, r0 \n\t" \ - "adc %B0, r1 \n\t" \ - "mul %D2, %B1 \n\t" \ - "add %B0, r0 \n\t" \ - "clr r1 \n\t" \ + A("clr r26") \ + A("mul %A1, %B2") \ + A("mov r27, r1") \ + A("mul %B1, %C2") \ + A("movw %A0, r0") \ + A("mul %C1, %C2") \ + A("add %B0, r0") \ + A("mul %C1, %B2") \ + A("add %A0, r0") \ + A("adc %B0, r1") \ + A("mul %A1, %C2") \ + A("add r27, r0") \ + A("adc %A0, r1") \ + A("adc %B0, r26") \ + A("mul %B1, %B2") \ + A("add r27, r0") \ + A("adc %A0, r1") \ + A("adc %B0, r26") \ + A("mul %C1, %A2") \ + A("add r27, r0") \ + A("adc %A0, r1") \ + A("adc %B0, r26") \ + A("mul %B1, %A2") \ + A("add r27, r1") \ + A("adc %A0, r26") \ + A("adc %B0, r26") \ + A("lsr r27") \ + A("adc %A0, r26") \ + A("adc %B0, r26") \ + A("mul %D2, %A1") \ + A("add %A0, r0") \ + A("adc %B0, r1") \ + A("mul %D2, %B1") \ + A("add %B0, r0") \ + A("clr r1") \ : \ "=&r" (intRes) \ : \ @@ -345,6 +365,732 @@ void Stepper::set_directions() { extern volatile uint8_t e_hit; #endif +#if ENABLED(BEZIER_JERK_CONTROL) + /** + * We are using a quintic (fifth-degree) Bézier polynomial for the velocity curve. + * This gives us a "linear pop" velocity curve; with pop being the sixth derivative of position: + * velocity - 1st, acceleration - 2nd, jerk - 3rd, snap - 4th, crackle - 5th, pop - 6th + * + * The Bézier curve takes the form: + * + * V(t) = P_0 * B_0(t) + P_1 * B_1(t) + P_2 * B_2(t) + P_3 * B_3(t) + P_4 * B_4(t) + P_5 * B_5(t) + * + * Where 0 <= t <= 1, and V(t) is the velocity. P_0 through P_5 are the control points, and B_0(t) + * through B_5(t) are the Bernstein basis as follows: + * + * B_0(t) = (1-t)^5 = -t^5 + 5t^4 - 10t^3 + 10t^2 - 5t + 1 + * B_1(t) = 5(1-t)^4 * t = 5t^5 - 20t^4 + 30t^3 - 20t^2 + 5t + * B_2(t) = 10(1-t)^3 * t^2 = -10t^5 + 30t^4 - 30t^3 + 10t^2 + * B_3(t) = 10(1-t)^2 * t^3 = 10t^5 - 20t^4 + 10t^3 + * B_4(t) = 5(1-t) * t^4 = -5t^5 + 5t^4 + * B_5(t) = t^5 = t^5 + * ^ ^ ^ ^ ^ ^ + * | | | | | | + * A B C D E F + * + * Unfortunately, we cannot use forward-differencing to calculate each position through + * the curve, as Marlin uses variable timer periods. So, we require a formula of the form: + * + * V_f(t) = A*t^5 + B*t^4 + C*t^3 + D*t^2 + E*t + F + * + * Looking at the above B_0(t) through B_5(t) expanded forms, if we take the coefficients of t^5 + * through t of the Bézier form of V(t), we can determine that: + * + * A = -P_0 + 5*P_1 - 10*P_2 + 10*P_3 - 5*P_4 + P_5 + * B = 5*P_0 - 20*P_1 + 30*P_2 - 20*P_3 + 5*P_4 + * C = -10*P_0 + 30*P_1 - 30*P_2 + 10*P_3 + * D = 10*P_0 - 20*P_1 + 10*P_2 + * E = - 5*P_0 + 5*P_1 + * F = P_0 + * + * Now, since we will (currently) *always* want the initial acceleration and jerk values to be 0, + * We set P_i = P_0 = P_1 = P_2 (initial velocity), and P_t = P_3 = P_4 = P_5 (target velocity), + * which, after simplification, resolves to: + * + * A = - 6*P_i + 6*P_t = 6*(P_t - P_i) + * B = 15*P_i - 15*P_t = 15*(P_i - P_t) + * C = -10*P_i + 10*P_t = 10*(P_t - P_i) + * D = 0 + * E = 0 + * F = P_i + * + * As the t is evaluated in non uniform steps here, there is no other way rather than evaluating + * the Bézier curve at each point: + * + * V_f(t) = A*t^5 + B*t^4 + C*t^3 + F [0 <= t <= 1] + * + * Floating point arithmetic execution time cost is prohibitive, so we will transform the math to + * use fixed point values to be able to evaluate it in realtime. Assuming a maximum of 250000 steps + * per second (driver pulses should at least be 2uS hi/2uS lo), and allocating 2 bits to avoid + * overflows on the evaluation of the Bézier curve, means we can use + * + * t: unsigned Q0.32 (0 <= t < 1) |range 0 to 0xFFFFFFFF unsigned + * A: signed Q24.7 , |range = +/- 250000 * 6 * 128 = +/- 192000000 = 0x0B71B000 | 28 bits + sign + * B: signed Q24.7 , |range = +/- 250000 *15 * 128 = +/- 480000000 = 0x1C9C3800 | 29 bits + sign + * C: signed Q24.7 , |range = +/- 250000 *10 * 128 = +/- 320000000 = 0x1312D000 | 29 bits + sign + * F: signed Q24.7 , |range = +/- 250000 * 128 = 32000000 = 0x01E84800 | 25 bits + sign + * + * The trapezoid generator state contains the following information, that we will use to create and evaluate + * the Bézier curve: + * + * blk->step_event_count [TS] = The total count of steps for this movement. (=distance) + * blk->initial_rate [VI] = The initial steps per second (=velocity) + * blk->final_rate [VF] = The ending steps per second (=velocity) + * and the count of events completed (step_events_completed) [CS] (=distance until now) + * + * Note the abbreviations we use in the following formulae are between []s + * + * For Any 32bit CPU: + * + * At the start of each trapezoid, we calculate the coefficients A,B,C,F and Advance [AV], as follows: + * + * A = 6*128*(VF - VI) = 768*(VF - VI) + * B = 15*128*(VI - VF) = 1920*(VI - VF) + * C = 10*128*(VF - VI) = 1280*(VF - VI) + * F = 128*VI = 128*VI + * AV = (1<<32)/TS ~= 0xFFFFFFFF / TS (To use ARM UDIV, that is 32 bits) (this is computed at the planner, to offload expensive calculations from the ISR) + * + * And for each point, we will evaluate the curve with the following sequence: + * + * void lsrs(uint32_t& d, uint32_t s, int cnt) { + * d = s >> cnt; + * } + * void lsls(uint32_t& d, uint32_t s, int cnt) { + * d = s << cnt; + * } + * void lsrs(int32_t& d, uint32_t s, int cnt) { + * d = uint32_t(s) >> cnt; + * } + * void lsls(int32_t& d, uint32_t s, int cnt) { + * d = uint32_t(s) << cnt; + * } + * void umull(uint32_t& rlo, uint32_t& rhi, uint32_t op1, uint32_t op2) { + * uint64_t res = uint64_t(op1) * op2; + * rlo = uint32_t(res & 0xFFFFFFFF); + * rhi = uint32_t((res >> 32) & 0xFFFFFFFF); + * } + * void smlal(int32_t& rlo, int32_t& rhi, int32_t op1, int32_t op2) { + * int64_t mul = int64_t(op1) * op2; + * int64_t s = int64_t(uint32_t(rlo) | ((uint64_t(uint32_t(rhi)) << 32U))); + * mul += s; + * rlo = int32_t(mul & 0xFFFFFFFF); + * rhi = int32_t((mul >> 32) & 0xFFFFFFFF); + * } + * int32_t _eval_bezier_curve_arm(uint32_t curr_step) { + * register uint32_t flo = 0; + * register uint32_t fhi = bezier_AV * curr_step; + * register uint32_t t = fhi; + * register int32_t alo = bezier_F; + * register int32_t ahi = 0; + * register int32_t A = bezier_A; + * register int32_t B = bezier_B; + * register int32_t C = bezier_C; + * + * lsrs(ahi, alo, 1); // a = F << 31 + * lsls(alo, alo, 31); // + * umull(flo, fhi, fhi, t); // f *= t + * umull(flo, fhi, fhi, t); // f>>=32; f*=t + * lsrs(flo, fhi, 1); // + * smlal(alo, ahi, flo, C); // a+=(f>>33)*C + * umull(flo, fhi, fhi, t); // f>>=32; f*=t + * lsrs(flo, fhi, 1); // + * smlal(alo, ahi, flo, B); // a+=(f>>33)*B + * umull(flo, fhi, fhi, t); // f>>=32; f*=t + * lsrs(flo, fhi, 1); // f>>=33; + * smlal(alo, ahi, flo, A); // a+=(f>>33)*A; + * lsrs(alo, ahi, 6); // a>>=38 + * + * return alo; + * } + * + * This will be rewritten in ARM assembly to get peak performance and will take 43 cycles to execute + * + * For AVR, we scale precision of coefficients to make it possible to evaluate the Bézier curve in + * realtime: Let's reduce precision as much as possible. After some experimentation we found that: + * + * Assume t and AV with 24 bits is enough + * A = 6*(VF - VI) + * B = 15*(VI - VF) + * C = 10*(VF - VI) + * F = VI + * AV = (1<<24)/TS (this is computed at the planner, to offload expensive calculations from the ISR) + * + * Instead of storing sign for each coefficient, we will store its absolute value, + * and flag the sign of the A coefficient, so we can save to store the sign bit. + * It always holds that sign(A) = - sign(B) = sign(C) + * + * So, the resulting range of the coefficients are: + * + * t: unsigned (0 <= t < 1) |range 0 to 0xFFFFFF unsigned + * A: signed Q24 , range = 250000 * 6 = 1500000 = 0x16E360 | 21 bits + * B: signed Q24 , range = 250000 *15 = 3750000 = 0x393870 | 22 bits + * C: signed Q24 , range = 250000 *10 = 2500000 = 0x1312D0 | 21 bits + * F: signed Q24 , range = 250000 = 250000 = 0x0ED090 | 20 bits + * + * And for each curve, we estimate its coefficients with: + * + * void _calc_bezier_curve_coeffs(int32_t v0, int32_t v1, uint32_t av) { + * // Calculate the Bézier coefficients + * if (v1 < v0) { + * A_negative = true; + * bezier_A = 6 * (v0 - v1); + * bezier_B = 15 * (v0 - v1); + * bezier_C = 10 * (v0 - v1); + * } + * else { + * A_negative = false; + * bezier_A = 6 * (v1 - v0); + * bezier_B = 15 * (v1 - v0); + * bezier_C = 10 * (v1 - v0); + * } + * bezier_F = v0; + * } + * + * And for each point, we will evaluate the curve with the following sequence: + * + * // unsigned multiplication of 24 bits x 24bits, return upper 16 bits + * void umul24x24to16hi(uint16_t& r, uint24_t op1, uint24_t op2) { + * r = (uint64_t(op1) * op2) >> 8; + * } + * // unsigned multiplication of 16 bits x 16bits, return upper 16 bits + * void umul16x16to16hi(uint16_t& r, uint16_t op1, uint16_t op2) { + * r = (uint32_t(op1) * op2) >> 16; + * } + * // unsigned multiplication of 16 bits x 24bits, return upper 24 bits + * void umul16x24to24hi(uint24_t& r, uint16_t op1, uint24_t op2) { + * r = uint24_t((uint64_t(op1) * op2) >> 16); + * } + * + * int32_t _eval_bezier_curve(uint32_t curr_step) { + * // To save computing, the first step is always the initial speed + * if (!curr_step) + * return bezier_F; + * + * uint16_t t; + * umul24x24to16hi(t, bezier_AV, curr_step); // t: Range 0 - 1^16 = 16 bits + * uint16_t f = t; + * umul16x16to16hi(f, f, t); // Range 16 bits (unsigned) + * umul16x16to16hi(f, f, t); // Range 16 bits : f = t^3 (unsigned) + * uint24_t acc = bezier_F; // Range 20 bits (unsigned) + * if (A_negative) { + * uint24_t v; + * umul16x24to24hi(v, f, bezier_C); // Range 21bits + * acc -= v; + * umul16x16to16hi(f, f, t); // Range 16 bits : f = t^4 (unsigned) + * umul16x24to24hi(v, f, bezier_B); // Range 22bits + * acc += v; + * umul16x16to16hi(f, f, t); // Range 16 bits : f = t^5 (unsigned) + * umul16x24to24hi(v, f, bezier_A); // Range 21bits + 15 = 36bits (plus sign) + * acc -= v; + * } + * else { + * uint24_t v; + * umul16x24to24hi(v, f, bezier_C); // Range 21bits + * acc += v; + * umul16x16to16hi(f, f, t); // Range 16 bits : f = t^4 (unsigned) + * umul16x24to24hi(v, f, bezier_B); // Range 22bits + * acc -= v; + * umul16x16to16hi(f, f, t); // Range 16 bits : f = t^5 (unsigned) + * umul16x24to24hi(v, f, bezier_A); // Range 21bits + 15 = 36bits (plus sign) + * acc += v; + * } + * return acc; + * } + * Those functions will be translated into assembler to get peak performance. coefficient calculations takes 70 cycles, + * Bezier point evaluation takes 150 cycles + * + */ + + // For AVR we use assembly to maximize speed + void Stepper::_calc_bezier_curve_coeffs(const int32_t v0, const int32_t v1, const uint32_t av) { + + // Store advance + bezier_AV = av; + + // Calculate the rest of the coefficients + register uint8_t r2 = v0 & 0xFF; + register uint8_t r3 = (v0 >> 8) & 0xFF; + register uint8_t r12 = (v0 >> 16) & 0xFF; + register uint8_t r5 = v1 & 0xFF; + register uint8_t r6 = (v1 >> 8) & 0xFF; + register uint8_t r7 = (v1 >> 16) & 0xFF; + register uint8_t r4,r8,r9,r10,r11; + + __asm__ __volatile__( + /* Calculate the Bézier coefficients */ + /* %10:%1:%0 = v0*/ + /* %5:%4:%3 = v1*/ + /* %7:%6:%10 = temporary*/ + /* %9 = val (must be high register!)*/ + /* %10 (must be high register!)*/ + + /* Store initial velocity*/ + A("sts bezier_F, %0") + A("sts bezier_F+1, %1") + A("sts bezier_F+2, %10") /* bezier_F = %10:%1:%0 = v0 */ + + /* Get delta speed */ + A("ldi %2,-1") /* %2 = 0xFF, means A_negative = true */ + A("clr %8") /* %8 = 0 */ + A("sub %0,%3") + A("sbc %1,%4") + A("sbc %10,%5") /* v0 -= v1, C=1 if result is negative */ + A("brcc 1f") /* branch if result is positive (C=0), that means v0 >= v1 */ + + /* Result was negative, get the absolute value*/ + A("com %10") + A("com %1") + A("neg %0") + A("sbc %1,%2") + A("sbc %10,%2") /* %10:%1:%0 +1 -> %10:%1:%0 = -(v0 - v1) = (v1 - v0) */ + A("clr %2") /* %2 = 0, means A_negative = false */ + + /* Store negative flag*/ + L("1") + A("sts A_negative, %2") /* Store negative flag */ + + /* Compute coefficients A,B and C [20 cycles worst case]*/ + A("ldi %9,6") /* %9 = 6 */ + A("mul %0,%9") /* r1:r0 = 6*LO(v0-v1) */ + A("sts bezier_A, r0") + A("mov %6,r1") + A("clr %7") /* %7:%6:r0 = 6*LO(v0-v1) */ + A("mul %1,%9") /* r1:r0 = 6*MI(v0-v1) */ + A("add %6,r0") + A("adc %7,r1") /* %7:%6:?? += 6*MI(v0-v1) << 8 */ + A("mul %10,%9") /* r1:r0 = 6*HI(v0-v1) */ + A("add %7,r0") /* %7:%6:?? += 6*HI(v0-v1) << 16 */ + A("sts bezier_A+1, %6") + A("sts bezier_A+2, %7") /* bezier_A = %7:%6:?? = 6*(v0-v1) [35 cycles worst] */ + + A("ldi %9,15") /* %9 = 15 */ + A("mul %0,%9") /* r1:r0 = 5*LO(v0-v1) */ + A("sts bezier_B, r0") + A("mov %6,r1") + A("clr %7") /* %7:%6:?? = 5*LO(v0-v1) */ + A("mul %1,%9") /* r1:r0 = 5*MI(v0-v1) */ + A("add %6,r0") + A("adc %7,r1") /* %7:%6:?? += 5*MI(v0-v1) << 8 */ + A("mul %10,%9") /* r1:r0 = 5*HI(v0-v1) */ + A("add %7,r0") /* %7:%6:?? += 5*HI(v0-v1) << 16 */ + A("sts bezier_B+1, %6") + A("sts bezier_B+2, %7") /* bezier_B = %7:%6:?? = 5*(v0-v1) [50 cycles worst] */ + + A("ldi %9,10") /* %9 = 10 */ + A("mul %0,%9") /* r1:r0 = 10*LO(v0-v1) */ + A("sts bezier_C, r0") + A("mov %6,r1") + A("clr %7") /* %7:%6:?? = 10*LO(v0-v1) */ + A("mul %1,%9") /* r1:r0 = 10*MI(v0-v1) */ + A("add %6,r0") + A("adc %7,r1") /* %7:%6:?? += 10*MI(v0-v1) << 8 */ + A("mul %10,%9") /* r1:r0 = 10*HI(v0-v1) */ + A("add %7,r0") /* %7:%6:?? += 10*HI(v0-v1) << 16 */ + A("sts bezier_C+1, %6") + " sts bezier_C+2, %7" /* bezier_C = %7:%6:?? = 10*(v0-v1) [65 cycles worst] */ + : "+r" (r2), + "+d" (r3), + "=r" (r4), + "+r" (r5), + "+r" (r6), + "+r" (r7), + "=r" (r8), + "=r" (r9), + "=r" (r10), + "=d" (r11), + "+r" (r12) + : + : "r0", "r1", "cc", "memory" + ); + } + + FORCE_INLINE int32_t Stepper::_eval_bezier_curve(const uint32_t curr_step) { + + // If dealing with the first step, save expensive computing and return the initial speed + if (!curr_step) + return bezier_F; + + register uint8_t r0 = 0; /* Zero register */ + register uint8_t r2 = (curr_step) & 0xFF; + register uint8_t r3 = (curr_step >> 8) & 0xFF; + register uint8_t r4 = (curr_step >> 16) & 0xFF; + register uint8_t r1,r5,r6,r7,r8,r9,r10,r11; /* Temporary registers */ + + __asm__ __volatile( + /* umul24x24to16hi(t, bezier_AV, curr_step); t: Range 0 - 1^16 = 16 bits*/ + A("lds %9,bezier_AV") /* %9 = LO(AV)*/ + A("mul %9,%2") /* r1:r0 = LO(bezier_AV)*LO(curr_step)*/ + A("mov %7,r1") /* %7 = LO(bezier_AV)*LO(curr_step) >> 8*/ + A("clr %8") /* %8:%7 = LO(bezier_AV)*LO(curr_step) >> 8*/ + A("lds %10,bezier_AV+1") /* %10 = MI(AV)*/ + A("mul %10,%2") /* r1:r0 = MI(bezier_AV)*LO(curr_step)*/ + A("add %7,r0") + A("adc %8,r1") /* %8:%7 += MI(bezier_AV)*LO(curr_step)*/ + A("lds r1,bezier_AV+2") /* r11 = HI(AV)*/ + A("mul r1,%2") /* r1:r0 = HI(bezier_AV)*LO(curr_step)*/ + A("add %8,r0") /* %8:%7 += HI(bezier_AV)*LO(curr_step) << 8*/ + A("mul %9,%3") /* r1:r0 = LO(bezier_AV)*MI(curr_step)*/ + A("add %7,r0") + A("adc %8,r1") /* %8:%7 += LO(bezier_AV)*MI(curr_step)*/ + A("mul %10,%3") /* r1:r0 = MI(bezier_AV)*MI(curr_step)*/ + A("add %8,r0") /* %8:%7 += LO(bezier_AV)*MI(curr_step) << 8*/ + A("mul %9,%4") /* r1:r0 = LO(bezier_AV)*HI(curr_step)*/ + A("add %8,r0") /* %8:%7 += LO(bezier_AV)*HI(curr_step) << 8*/ + /* %8:%7 = t*/ + + /* uint16_t f = t;*/ + A("mov %5,%7") /* %6:%5 = f*/ + A("mov %6,%8") + /* %6:%5 = f*/ + + /* umul16x16to16hi(f, f, t); / Range 16 bits (unsigned) [17] */ + A("mul %5,%7") /* r1:r0 = LO(f) * LO(t)*/ + A("mov %9,r1") /* store MIL(LO(f) * LO(t)) in %9, we need it for rounding*/ + A("clr %10") /* %10 = 0*/ + A("clr %11") /* %11 = 0*/ + A("mul %5,%8") /* r1:r0 = LO(f) * HI(t)*/ + A("add %9,r0") /* %9 += LO(LO(f) * HI(t))*/ + A("adc %10,r1") /* %10 = HI(LO(f) * HI(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%7") /* r1:r0 = HI(f) * LO(t)*/ + A("add %9,r0") /* %9 += LO(HI(f) * LO(t))*/ + A("adc %10,r1") /* %10 += HI(HI(f) * LO(t)) */ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%8") /* r1:r0 = HI(f) * HI(t)*/ + A("add %10,r0") /* %10 += LO(HI(f) * HI(t))*/ + A("adc %11,r1") /* %11 += HI(HI(f) * HI(t))*/ + A("mov %5,%10") /* %6:%5 = */ + A("mov %6,%11") /* f = %10:%11*/ + + /* umul16x16to16hi(f, f, t); / Range 16 bits : f = t^3 (unsigned) [17]*/ + A("mul %5,%7") /* r1:r0 = LO(f) * LO(t)*/ + A("mov %1,r1") /* store MIL(LO(f) * LO(t)) in %1, we need it for rounding*/ + A("clr %10") /* %10 = 0*/ + A("clr %11") /* %11 = 0*/ + A("mul %5,%8") /* r1:r0 = LO(f) * HI(t)*/ + A("add %1,r0") /* %1 += LO(LO(f) * HI(t))*/ + A("adc %10,r1") /* %10 = HI(LO(f) * HI(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%7") /* r1:r0 = HI(f) * LO(t)*/ + A("add %1,r0") /* %1 += LO(HI(f) * LO(t))*/ + A("adc %10,r1") /* %10 += HI(HI(f) * LO(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%8") /* r1:r0 = HI(f) * HI(t)*/ + A("add %10,r0") /* %10 += LO(HI(f) * HI(t))*/ + A("adc %11,r1") /* %11 += HI(HI(f) * HI(t))*/ + A("mov %5,%10") /* %6:%5 =*/ + A("mov %6,%11") /* f = %10:%11*/ + /* [15 +17*2] = [49]*/ + + /* %4:%3:%2 will be acc from now on*/ + + /* uint24_t acc = bezier_F; / Range 20 bits (unsigned)*/ + A("clr %9") /* "decimal place we get for free"*/ + A("lds %2,bezier_F") + A("lds %3,bezier_F+1") + A("lds %4,bezier_F+2") /* %4:%3:%2 = acc*/ + + /* if (A_negative) {*/ + A("lds r0,A_negative") + A("or r0,%0") /* Is flag signalling negative? */ + A("brne 3f") /* If yes, Skip next instruction if A was negative*/ + A("rjmp 1f") /* Otherwise, jump */ + + /* uint24_t v; */ + /* umul16x24to24hi(v, f, bezier_C); / Range 21bits [29] */ + /* acc -= v; */ + L("3") + A("lds %10, bezier_C") /* %10 = LO(bezier_C)*/ + A("mul %10,%5") /* r1:r0 = LO(bezier_C) * LO(f)*/ + A("sub %9,r1") + A("sbc %2,%0") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= HI(LO(bezier_C) * LO(f))*/ + A("lds %11, bezier_C+1") /* %11 = MI(bezier_C)*/ + A("mul %11,%5") /* r1:r0 = MI(bezier_C) * LO(f)*/ + A("sub %9,r0") + A("sbc %2,r1") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= MI(bezier_C) * LO(f)*/ + A("lds %1, bezier_C+2") /* %1 = HI(bezier_C)*/ + A("mul %1,%5") /* r1:r0 = MI(bezier_C) * LO(f)*/ + A("sub %2,r0") + A("sbc %3,r1") + A("sbc %4,%0") /* %4:%3:%2:%9 -= HI(bezier_C) * LO(f) << 8*/ + A("mul %10,%6") /* r1:r0 = LO(bezier_C) * MI(f)*/ + A("sub %9,r0") + A("sbc %2,r1") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= LO(bezier_C) * MI(f)*/ + A("mul %11,%6") /* r1:r0 = MI(bezier_C) * MI(f)*/ + A("sub %2,r0") + A("sbc %3,r1") + A("sbc %4,%0") /* %4:%3:%2:%9 -= MI(bezier_C) * MI(f) << 8*/ + A("mul %1,%6") /* r1:r0 = HI(bezier_C) * LO(f)*/ + A("sub %3,r0") + A("sbc %4,r1") /* %4:%3:%2:%9 -= HI(bezier_C) * LO(f) << 16*/ + + /* umul16x16to16hi(f, f, t); / Range 16 bits : f = t^3 (unsigned) [17]*/ + A("mul %5,%7") /* r1:r0 = LO(f) * LO(t)*/ + A("mov %1,r1") /* store MIL(LO(f) * LO(t)) in %1, we need it for rounding*/ + A("clr %10") /* %10 = 0*/ + A("clr %11") /* %11 = 0*/ + A("mul %5,%8") /* r1:r0 = LO(f) * HI(t)*/ + A("add %1,r0") /* %1 += LO(LO(f) * HI(t))*/ + A("adc %10,r1") /* %10 = HI(LO(f) * HI(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%7") /* r1:r0 = HI(f) * LO(t)*/ + A("add %1,r0") /* %1 += LO(HI(f) * LO(t))*/ + A("adc %10,r1") /* %10 += HI(HI(f) * LO(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%8") /* r1:r0 = HI(f) * HI(t)*/ + A("add %10,r0") /* %10 += LO(HI(f) * HI(t))*/ + A("adc %11,r1") /* %11 += HI(HI(f) * HI(t))*/ + A("mov %5,%10") /* %6:%5 =*/ + A("mov %6,%11") /* f = %10:%11*/ + + /* umul16x24to24hi(v, f, bezier_B); / Range 22bits [29]*/ + /* acc += v; */ + A("lds %10, bezier_B") /* %10 = LO(bezier_B)*/ + A("mul %10,%5") /* r1:r0 = LO(bezier_B) * LO(f)*/ + A("add %9,r1") + A("adc %2,%0") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += HI(LO(bezier_B) * LO(f))*/ + A("lds %11, bezier_B+1") /* %11 = MI(bezier_B)*/ + A("mul %11,%5") /* r1:r0 = MI(bezier_B) * LO(f)*/ + A("add %9,r0") + A("adc %2,r1") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += MI(bezier_B) * LO(f)*/ + A("lds %1, bezier_B+2") /* %1 = HI(bezier_B)*/ + A("mul %1,%5") /* r1:r0 = MI(bezier_B) * LO(f)*/ + A("add %2,r0") + A("adc %3,r1") + A("adc %4,%0") /* %4:%3:%2:%9 += HI(bezier_B) * LO(f) << 8*/ + A("mul %10,%6") /* r1:r0 = LO(bezier_B) * MI(f)*/ + A("add %9,r0") + A("adc %2,r1") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += LO(bezier_B) * MI(f)*/ + A("mul %11,%6") /* r1:r0 = MI(bezier_B) * MI(f)*/ + A("add %2,r0") + A("adc %3,r1") + A("adc %4,%0") /* %4:%3:%2:%9 += MI(bezier_B) * MI(f) << 8*/ + A("mul %1,%6") /* r1:r0 = HI(bezier_B) * LO(f)*/ + A("add %3,r0") + A("adc %4,r1") /* %4:%3:%2:%9 += HI(bezier_B) * LO(f) << 16*/ + + /* umul16x16to16hi(f, f, t); / Range 16 bits : f = t^5 (unsigned) [17]*/ + A("mul %5,%7") /* r1:r0 = LO(f) * LO(t)*/ + A("mov %1,r1") /* store MIL(LO(f) * LO(t)) in %1, we need it for rounding*/ + A("clr %10") /* %10 = 0*/ + A("clr %11") /* %11 = 0*/ + A("mul %5,%8") /* r1:r0 = LO(f) * HI(t)*/ + A("add %1,r0") /* %1 += LO(LO(f) * HI(t))*/ + A("adc %10,r1") /* %10 = HI(LO(f) * HI(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%7") /* r1:r0 = HI(f) * LO(t)*/ + A("add %1,r0") /* %1 += LO(HI(f) * LO(t))*/ + A("adc %10,r1") /* %10 += HI(HI(f) * LO(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%8") /* r1:r0 = HI(f) * HI(t)*/ + A("add %10,r0") /* %10 += LO(HI(f) * HI(t))*/ + A("adc %11,r1") /* %11 += HI(HI(f) * HI(t))*/ + A("mov %5,%10") /* %6:%5 =*/ + A("mov %6,%11") /* f = %10:%11*/ + + /* umul16x24to24hi(v, f, bezier_A); / Range 21bits [29]*/ + /* acc -= v; */ + A("lds %10, bezier_A") /* %10 = LO(bezier_A)*/ + A("mul %10,%5") /* r1:r0 = LO(bezier_A) * LO(f)*/ + A("sub %9,r1") + A("sbc %2,%0") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= HI(LO(bezier_A) * LO(f))*/ + A("lds %11, bezier_A+1") /* %11 = MI(bezier_A)*/ + A("mul %11,%5") /* r1:r0 = MI(bezier_A) * LO(f)*/ + A("sub %9,r0") + A("sbc %2,r1") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= MI(bezier_A) * LO(f)*/ + A("lds %1, bezier_A+2") /* %1 = HI(bezier_A)*/ + A("mul %1,%5") /* r1:r0 = MI(bezier_A) * LO(f)*/ + A("sub %2,r0") + A("sbc %3,r1") + A("sbc %4,%0") /* %4:%3:%2:%9 -= HI(bezier_A) * LO(f) << 8*/ + A("mul %10,%6") /* r1:r0 = LO(bezier_A) * MI(f)*/ + A("sub %9,r0") + A("sbc %2,r1") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= LO(bezier_A) * MI(f)*/ + A("mul %11,%6") /* r1:r0 = MI(bezier_A) * MI(f)*/ + A("sub %2,r0") + A("sbc %3,r1") + A("sbc %4,%0") /* %4:%3:%2:%9 -= MI(bezier_A) * MI(f) << 8*/ + A("mul %1,%6") /* r1:r0 = HI(bezier_A) * LO(f)*/ + A("sub %3,r0") + A("sbc %4,r1") /* %4:%3:%2:%9 -= HI(bezier_A) * LO(f) << 16*/ + A("jmp 2f") /* Done!*/ + + L("1") + + /* uint24_t v; */ + /* umul16x24to24hi(v, f, bezier_C); / Range 21bits [29]*/ + /* acc += v; */ + A("lds %10, bezier_C") /* %10 = LO(bezier_C)*/ + A("mul %10,%5") /* r1:r0 = LO(bezier_C) * LO(f)*/ + A("add %9,r1") + A("adc %2,%0") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += HI(LO(bezier_C) * LO(f))*/ + A("lds %11, bezier_C+1") /* %11 = MI(bezier_C)*/ + A("mul %11,%5") /* r1:r0 = MI(bezier_C) * LO(f)*/ + A("add %9,r0") + A("adc %2,r1") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += MI(bezier_C) * LO(f)*/ + A("lds %1, bezier_C+2") /* %1 = HI(bezier_C)*/ + A("mul %1,%5") /* r1:r0 = MI(bezier_C) * LO(f)*/ + A("add %2,r0") + A("adc %3,r1") + A("adc %4,%0") /* %4:%3:%2:%9 += HI(bezier_C) * LO(f) << 8*/ + A("mul %10,%6") /* r1:r0 = LO(bezier_C) * MI(f)*/ + A("add %9,r0") + A("adc %2,r1") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += LO(bezier_C) * MI(f)*/ + A("mul %11,%6") /* r1:r0 = MI(bezier_C) * MI(f)*/ + A("add %2,r0") + A("adc %3,r1") + A("adc %4,%0") /* %4:%3:%2:%9 += MI(bezier_C) * MI(f) << 8*/ + A("mul %1,%6") /* r1:r0 = HI(bezier_C) * LO(f)*/ + A("add %3,r0") + A("adc %4,r1") /* %4:%3:%2:%9 += HI(bezier_C) * LO(f) << 16*/ + + /* umul16x16to16hi(f, f, t); / Range 16 bits : f = t^3 (unsigned) [17]*/ + A("mul %5,%7") /* r1:r0 = LO(f) * LO(t)*/ + A("mov %1,r1") /* store MIL(LO(f) * LO(t)) in %1, we need it for rounding*/ + A("clr %10") /* %10 = 0*/ + A("clr %11") /* %11 = 0*/ + A("mul %5,%8") /* r1:r0 = LO(f) * HI(t)*/ + A("add %1,r0") /* %1 += LO(LO(f) * HI(t))*/ + A("adc %10,r1") /* %10 = HI(LO(f) * HI(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%7") /* r1:r0 = HI(f) * LO(t)*/ + A("add %1,r0") /* %1 += LO(HI(f) * LO(t))*/ + A("adc %10,r1") /* %10 += HI(HI(f) * LO(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%8") /* r1:r0 = HI(f) * HI(t)*/ + A("add %10,r0") /* %10 += LO(HI(f) * HI(t))*/ + A("adc %11,r1") /* %11 += HI(HI(f) * HI(t))*/ + A("mov %5,%10") /* %6:%5 =*/ + A("mov %6,%11") /* f = %10:%11*/ + + /* umul16x24to24hi(v, f, bezier_B); / Range 22bits [29]*/ + /* acc -= v;*/ + A("lds %10, bezier_B") /* %10 = LO(bezier_B)*/ + A("mul %10,%5") /* r1:r0 = LO(bezier_B) * LO(f)*/ + A("sub %9,r1") + A("sbc %2,%0") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= HI(LO(bezier_B) * LO(f))*/ + A("lds %11, bezier_B+1") /* %11 = MI(bezier_B)*/ + A("mul %11,%5") /* r1:r0 = MI(bezier_B) * LO(f)*/ + A("sub %9,r0") + A("sbc %2,r1") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= MI(bezier_B) * LO(f)*/ + A("lds %1, bezier_B+2") /* %1 = HI(bezier_B)*/ + A("mul %1,%5") /* r1:r0 = MI(bezier_B) * LO(f)*/ + A("sub %2,r0") + A("sbc %3,r1") + A("sbc %4,%0") /* %4:%3:%2:%9 -= HI(bezier_B) * LO(f) << 8*/ + A("mul %10,%6") /* r1:r0 = LO(bezier_B) * MI(f)*/ + A("sub %9,r0") + A("sbc %2,r1") + A("sbc %3,%0") + A("sbc %4,%0") /* %4:%3:%2:%9 -= LO(bezier_B) * MI(f)*/ + A("mul %11,%6") /* r1:r0 = MI(bezier_B) * MI(f)*/ + A("sub %2,r0") + A("sbc %3,r1") + A("sbc %4,%0") /* %4:%3:%2:%9 -= MI(bezier_B) * MI(f) << 8*/ + A("mul %1,%6") /* r1:r0 = HI(bezier_B) * LO(f)*/ + A("sub %3,r0") + A("sbc %4,r1") /* %4:%3:%2:%9 -= HI(bezier_B) * LO(f) << 16*/ + + /* umul16x16to16hi(f, f, t); / Range 16 bits : f = t^5 (unsigned) [17]*/ + A("mul %5,%7") /* r1:r0 = LO(f) * LO(t)*/ + A("mov %1,r1") /* store MIL(LO(f) * LO(t)) in %1, we need it for rounding*/ + A("clr %10") /* %10 = 0*/ + A("clr %11") /* %11 = 0*/ + A("mul %5,%8") /* r1:r0 = LO(f) * HI(t)*/ + A("add %1,r0") /* %1 += LO(LO(f) * HI(t))*/ + A("adc %10,r1") /* %10 = HI(LO(f) * HI(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%7") /* r1:r0 = HI(f) * LO(t)*/ + A("add %1,r0") /* %1 += LO(HI(f) * LO(t))*/ + A("adc %10,r1") /* %10 += HI(HI(f) * LO(t))*/ + A("adc %11,%0") /* %11 += carry*/ + A("mul %6,%8") /* r1:r0 = HI(f) * HI(t)*/ + A("add %10,r0") /* %10 += LO(HI(f) * HI(t))*/ + A("adc %11,r1") /* %11 += HI(HI(f) * HI(t))*/ + A("mov %5,%10") /* %6:%5 =*/ + A("mov %6,%11") /* f = %10:%11*/ + + /* umul16x24to24hi(v, f, bezier_A); / Range 21bits [29]*/ + /* acc += v; */ + A("lds %10, bezier_A") /* %10 = LO(bezier_A)*/ + A("mul %10,%5") /* r1:r0 = LO(bezier_A) * LO(f)*/ + A("add %9,r1") + A("adc %2,%0") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += HI(LO(bezier_A) * LO(f))*/ + A("lds %11, bezier_A+1") /* %11 = MI(bezier_A)*/ + A("mul %11,%5") /* r1:r0 = MI(bezier_A) * LO(f)*/ + A("add %9,r0") + A("adc %2,r1") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += MI(bezier_A) * LO(f)*/ + A("lds %1, bezier_A+2") /* %1 = HI(bezier_A)*/ + A("mul %1,%5") /* r1:r0 = MI(bezier_A) * LO(f)*/ + A("add %2,r0") + A("adc %3,r1") + A("adc %4,%0") /* %4:%3:%2:%9 += HI(bezier_A) * LO(f) << 8*/ + A("mul %10,%6") /* r1:r0 = LO(bezier_A) * MI(f)*/ + A("add %9,r0") + A("adc %2,r1") + A("adc %3,%0") + A("adc %4,%0") /* %4:%3:%2:%9 += LO(bezier_A) * MI(f)*/ + A("mul %11,%6") /* r1:r0 = MI(bezier_A) * MI(f)*/ + A("add %2,r0") + A("adc %3,r1") + A("adc %4,%0") /* %4:%3:%2:%9 += MI(bezier_A) * MI(f) << 8*/ + A("mul %1,%6") /* r1:r0 = HI(bezier_A) * LO(f)*/ + A("add %3,r0") + A("adc %4,r1") /* %4:%3:%2:%9 += HI(bezier_A) * LO(f) << 16*/ + L("2") + " clr __zero_reg__" /* C runtime expects r1 = __zero_reg__ = 0 */ + : "+r"(r0), + "+r"(r1), + "+r"(r2), + "+r"(r3), + "+r"(r4), + "+r"(r5), + "+r"(r6), + "+r"(r7), + "+r"(r8), + "+r"(r9), + "+r"(r10), + "+r"(r11) + : + :"cc","r0","r1" + ); + return (r2 | (uint16_t(r3) << 8)) | (uint32_t(r4) << 16); + } + +#endif // BEZIER_JERK_CONTROL + /** * Stepper Driver Interrupt * @@ -463,7 +1209,54 @@ void Stepper::isr() { if (!(current_block = planner.get_current_block())) return; } - trapezoid_generator_reset(); + // Initialize the trapezoid generator from the current block. + static int8_t last_extruder = -1; + + #if ENABLED(LIN_ADVANCE) + #if E_STEPPERS > 1 + if (current_block->active_extruder != last_extruder) { + current_adv_steps = 0; // If the now active extruder wasn't in use during the last move, its pressure is most likely gone. + LA_active_extruder = current_block->active_extruder; + } + #endif + + if ((use_advance_lead = current_block->use_advance_lead)) { + LA_decelerate_after = current_block->decelerate_after; + final_adv_steps = current_block->final_adv_steps; + max_adv_steps = current_block->max_adv_steps; + } + #endif + + if (current_block->direction_bits != last_direction_bits || current_block->active_extruder != last_extruder) { + last_direction_bits = current_block->direction_bits; + last_extruder = current_block->active_extruder; + set_directions(); + } + + // No acceleration / deceleration time elapsed so far + acceleration_time = deceleration_time = 0; + + // No step events completed so far + step_events_completed = 0; + + // step_rate to timer interval + OCR1A_nominal = calc_timer_interval(current_block->nominal_rate); + + // make a note of the number of step loops required at nominal speed + step_loops_nominal = step_loops; + + #if DISABLED(BEZIER_JERK_CONTROL) + // Set as deceleration point the initial rate of the block + acc_step_rate = current_block->initial_rate; + #endif + + #if ENABLED(BEZIER_JERK_CONTROL) + // Initialize the Bézier speed curve + _calc_bezier_curve_coeffs(current_block->initial_rate, current_block->cruise_rate, current_block->acceleration_time_inverse); + + // We have not started the 2nd half of the trapezoid + bezier_2nd_half = false; + #endif // Initialize Bresenham counters to 1/2 the ceiling counter_X = counter_Y = counter_Z = counter_E = -(current_block->step_event_count >> 1); @@ -705,11 +1498,19 @@ void Stepper::isr() { // Calculate new timer value if (step_events_completed <= (uint32_t)current_block->accelerate_until) { - MultiU24X32toH16(acc_step_rate, acceleration_time, current_block->acceleration_rate); - acc_step_rate += current_block->initial_rate; + #if ENABLED(BEZIER_JERK_CONTROL) + // Get the next speed to use (Jerk limited!) + uint16_t acc_step_rate = + acceleration_time < current_block->acceleration_time + ? _eval_bezier_curve(acceleration_time) + : current_block->cruise_rate; + #else + MultiU24X32toH16(acc_step_rate, acceleration_time, current_block->acceleration_rate); + acc_step_rate += current_block->initial_rate; - // upper limit - NOMORE(acc_step_rate, current_block->nominal_rate); + // upper limit + NOMORE(acc_step_rate, current_block->nominal_rate); + #endif // step_rate to timer interval const uint16_t interval = calc_timer_interval(acc_step_rate); @@ -734,14 +1535,32 @@ void Stepper::isr() { } else if (step_events_completed > (uint32_t)current_block->decelerate_after) { uint16_t step_rate; - MultiU24X32toH16(step_rate, deceleration_time, current_block->acceleration_rate); - if (step_rate < acc_step_rate) { // Still decelerating? - step_rate = acc_step_rate - step_rate; - NOLESS(step_rate, current_block->final_rate); - } - else - step_rate = current_block->final_rate; + #if ENABLED(BEZIER_JERK_CONTROL) + // If this is the 1st time we process the 2nd half of the trapezoid... + if (!bezier_2nd_half) { + + // Initialize the Bézier speed curve + _calc_bezier_curve_coeffs(current_block->cruise_rate, current_block->final_rate, current_block->deceleration_time_inverse); + bezier_2nd_half = true; + } + + // Calculate the next speed to use + step_rate = deceleration_time < current_block->deceleration_time + ? _eval_bezier_curve(deceleration_time) + : current_block->final_rate; + #else + + // Using the old trapezoidal control + MultiU24X32toH16(step_rate, deceleration_time, current_block->acceleration_rate); + + if (step_rate < acc_step_rate) { // Still decelerating? + step_rate = acc_step_rate - step_rate; + NOLESS(step_rate, current_block->final_rate); + } + else + step_rate = current_block->final_rate; + #endif // step_rate to timer interval const uint16_t interval = calc_timer_interval(step_rate); @@ -1104,6 +1923,7 @@ void Stepper::init() { // Init Stepper ISR to 122 Hz for quick starting OCR1A = 0x4000; TCNT1 = 0; + ENABLE_STEPPER_DRIVER_INTERRUPT(); endstops.enable(true); // Start with endstops active. After homing they can be disabled diff --git a/Marlin/stepper.h b/Marlin/stepper.h index 597600e805..087b8593e4 100644 --- a/Marlin/stepper.h +++ b/Marlin/stepper.h @@ -55,6 +55,7 @@ extern Stepper stepper; #define ENABLE_STEPPER_DRIVER_INTERRUPT() SBI(TIMSK1, OCIE1A) #define DISABLE_STEPPER_DRIVER_INTERRUPT() CBI(TIMSK1, OCIE1A) #define STEPPER_ISR_ENABLED() TEST(TIMSK1, OCIE1A) +#define HAL_STEPPER_TIMER_RATE ((F_CPU) * 0.125) // intRes = intIn1 * intIn2 >> 16 // uses: @@ -62,16 +63,16 @@ extern Stepper stepper; // r27 to store the byte 1 of the 24 bit result #define MultiU16X8toH16(intRes, charIn1, intIn2) \ asm volatile ( \ - "clr r26 \n\t" \ - "mul %A1, %B2 \n\t" \ - "movw %A0, r0 \n\t" \ - "mul %A1, %A2 \n\t" \ - "add %A0, r1 \n\t" \ - "adc %B0, r26 \n\t" \ - "lsr r0 \n\t" \ - "adc %A0, r26 \n\t" \ - "adc %B0, r26 \n\t" \ - "clr r1 \n\t" \ + A("clr r26") \ + A("mul %A1, %B2") \ + A("movw %A0, r0") \ + A("mul %A1, %A2") \ + A("add %A0, r1") \ + A("adc %B0, r26") \ + A("lsr r0") \ + A("adc %A0, r26") \ + A("adc %B0, r26") \ + A("clr r1") \ : \ "=&r" (intRes) \ : \ @@ -122,6 +123,16 @@ class Stepper { static int32_t counter_X, counter_Y, counter_Z, counter_E; static volatile uint32_t step_events_completed; // The number of step events executed in the current block + #if ENABLED(BEZIER_JERK_CONTROL) + static int32_t bezier_A, // A coefficient in Bézier speed curve + bezier_B, // B coefficient in Bézier speed curve + bezier_C; // C coefficient in Bézier speed curve + static uint32_t bezier_F, // F coefficient in Bézier speed curve + bezier_AV; // AV coefficient in Bézier speed curve + static bool A_negative, // If A coefficient was negative + bezier_2nd_half; // If Bézier curve has been initialized or not + #endif + #if ENABLED(LIN_ADVANCE) static uint32_t LA_decelerate_after; // Copy from current executed block. Needed because current_block is set to NULL "too early". @@ -145,8 +156,10 @@ class Stepper { static int32_t acceleration_time, deceleration_time; static uint8_t step_loops, step_loops_nominal; - static uint16_t OCR1A_nominal, - acc_step_rate; // needed for deceleration start point + static uint16_t OCR1A_nominal; + #if DISABLED(BEZIER_JERK_CONTROL) + static uint16_t acc_step_rate; // needed for deceleration start point + #endif static volatile int32_t endstops_trigsteps[XYZ]; static volatile int32_t endstops_stepsTotal, endstops_stepsDone; @@ -330,8 +343,8 @@ class Stepper { private: - FORCE_INLINE static unsigned short calc_timer_interval(unsigned short step_rate) { - unsigned short timer; + FORCE_INLINE static uint16_t calc_timer_interval(uint16_t step_rate) { + uint16_t timer; NOMORE(step_rate, MAX_STEP_FREQUENCY); @@ -370,43 +383,10 @@ class Stepper { return timer; } - // Initialize the trapezoid generator from the current block. - // Called whenever a new block begins. - FORCE_INLINE static void trapezoid_generator_reset() { - - static int8_t last_extruder = -1; - - #if ENABLED(LIN_ADVANCE) - #if E_STEPPERS > 1 - if (current_block->active_extruder != last_extruder) { - current_adv_steps = 0; // If the now active extruder wasn't in use during the last move, its pressure is most likely gone. - LA_active_extruder = current_block->active_extruder; - } - #endif - - if ((use_advance_lead = current_block->use_advance_lead)) { - LA_decelerate_after = current_block->decelerate_after; - final_adv_steps = current_block->final_adv_steps; - max_adv_steps = current_block->max_adv_steps; - } - #endif - - if (current_block->direction_bits != last_direction_bits || current_block->active_extruder != last_extruder) { - last_direction_bits = current_block->direction_bits; - last_extruder = current_block->active_extruder; - set_directions(); - } - - deceleration_time = 0; - // step_rate to timer interval - OCR1A_nominal = calc_timer_interval(current_block->nominal_rate); - // make a note of the number of step loops required at nominal speed - step_loops_nominal = step_loops; - acc_step_rate = current_block->initial_rate; - acceleration_time = calc_timer_interval(acc_step_rate); - _NEXT_ISR(acceleration_time); - - } + #if ENABLED(BEZIER_JERK_CONTROL) + static void _calc_bezier_curve_coeffs(const int32_t v0, const int32_t v1, const uint32_t av); + static int32_t _eval_bezier_curve(const uint32_t curr_step); + #endif #if HAS_DIGIPOTSS || HAS_MOTOR_CURRENT_PWM static void digipot_init();