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|
/*
* DDA.cpp
*
* Created on: 7 Dec 2014
* Author: David
*/
#include "RepRapFirmware.h"
#ifdef DUET_NG
# define DDA_MOVE_DEBUG (1)
#else
// On the wired Duets we don't have enough RAM to support this
# define DDA_MOVE_DEBUG (0)
#endif
#if DDA_MOVE_DEBUG
// Structure to hold the essential parameters of a move, for debugging
struct MoveParameters
{
float accelDistance;
float steadyDistance;
float decelDistance;
float startSpeed;
float topSpeed;
float endSpeed;
MoveParameters()
{
accelDistance = steadyDistance = decelDistance = startSpeed = topSpeed = endSpeed = 0.0;
}
};
const size_t NumSavedMoves = 256;
static MoveParameters savedMoves[NumSavedMoves];
static size_t savedMovePointer = 0;
// Print the saved moves in CSV format for analysis
/*static*/ void DDA::PrintMoves()
{
// Print the saved moved in CSV format
for (size_t i = 0; i < NumSavedMoves; ++i)
{
const MoveParameters& m = savedMoves[savedMovePointer];
reprap.GetPlatform()->MessageF(DEBUG_MESSAGE, "%f,%f,%f,%f,%f,%f\n", m.accelDistance, m.steadyDistance, m.decelDistance, m.startSpeed, m.topSpeed, m.endSpeed);
savedMovePointer = (savedMovePointer + 1) % NumSavedMoves;
}
}
#else
/*static*/ void DDA::PrintMoves() { }
#endif
#if DDA_LOG_PROBE_CHANGES
size_t DDA::numLoggedProbePositions = 0;
int32_t DDA::loggedProbePositions[MIN_AXES * MaxLoggedProbePositions];
bool DDA::probeTriggered = false;
void DDA::LogProbePosition()
{
if (numLoggedProbePositions < MaxLoggedProbePositions)
{
int32_t *p = loggedProbePositions + (numLoggedProbePositions * MIN_AXES);
for (size_t drive = 0; drive < MIN_AXES; ++drive)
{
DriveMovement& dm = ddm[drive];
if (dm.state == DMState::moving)
{
p[drive] = endPoint[drive] - dm.GetNetStepsLeft();
}
else
{
p[drive] = endPoint[drive];
}
}
++numLoggedProbePositions;
}
}
#endif
DDA::DDA(DDA* n) : next(n), prev(nullptr), state(empty)
{
memset(ddm, 0, sizeof(ddm)); //DEBUG to clear stepError field
}
// Return the number of clocks this DDA still needs to execute.
// This could be slightly negative, if the move is overdue for completion.
int32_t DDA::GetTimeLeft() const
pre(state == executing || state == frozen || state == completed)
{
return (state == completed) ? 0
: (state == executing) ? (int32_t)(moveStartTime + clocksNeeded - Platform::GetInterruptClocks())
: (int32_t)clocksNeeded;
}
void DDA::DebugPrintVector(const char *name, const float *vec, size_t len) const
{
debugPrintf("%s=", name);
for (size_t i = 0; i < len; ++i)
{
debugPrintf("%c%f", ((i == 0) ? '[' : ' '), vec[i]);
}
debugPrintf("]");
}
void DDA::DebugPrint() const
{
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
debugPrintf("DDA:");
if (endCoordinatesValid)
{
float startCoordinates[MAX_AXES];
for (size_t i = 0; i < numAxes; ++i)
{
startCoordinates[i] = endCoordinates[i] - (totalDistance * directionVector[i]);
}
DebugPrintVector(" start", startCoordinates, numAxes);
DebugPrintVector(" end", endCoordinates, numAxes);
}
debugPrintf(" d=%f", totalDistance);
DebugPrintVector(" vec", directionVector, 5);
debugPrintf("\na=%f reqv=%f topv=%f startv=%f endv=%f\n"
"daccel=%f ddecel=%f cks=%u\n",
acceleration, requestedSpeed, topSpeed, startSpeed, endSpeed,
accelDistance, decelDistance, clocksNeeded);
for (size_t axis = 0; axis < numAxes; ++axis)
{
ddm[axis].DebugPrint(reprap.GetGCodes()->axisLetters[axis], isDeltaMovement);
}
for (size_t i = numAxes; i < DRIVES; ++i)
{
if (ddm[i].state != DMState::idle)
{
ddm[i].DebugPrint((char)('0' + (i - numAxes)), false);
}
}
}
// This is called by Move to initialize all DDAs
void DDA::Init()
{
// Set the endpoints to zero, because Move asks for them.
// They will be wrong if we are on a delta. We take care of that when we process the M665 command in config.g.
for (size_t drive = 0; drive < DRIVES; ++drive)
{
endPoint[drive] = 0;
ddm[drive].state = DMState::idle;
}
state = empty;
endCoordinatesValid = false;
}
// Set up a real move. Return true if it represents real movement, else false.
bool DDA::Init(const GCodes::RawMove &nextMove, bool doMotorMapping)
{
// 1. Compute the new endpoints and the movement vector
const int32_t * const positionNow = prev->DriveCoordinates();
const Move * const move = reprap.GetMove();
if (doMotorMapping)
{
move->MotorTransform(nextMove.coords, endPoint); // transform the axis coordinates if on a delta or CoreXY printer
isDeltaMovement = move->IsDeltaMode()
&& (endPoint[X_AXIS] != positionNow[X_AXIS] || endPoint[Y_AXIS] != positionNow[Y_AXIS] || endPoint[Z_AXIS] != positionNow[Z_AXIS]);
}
else
{
isDeltaMovement = false;
}
isPrintingMove = false;
bool realMove = false, xyMoving = false;
const bool isSpecialDeltaMove = (move->IsDeltaMode() && !doMotorMapping);
float accelerations[DRIVES];
const float * const normalAccelerations = reprap.GetPlatform()->Accelerations();
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
for (size_t drive = 0; drive < DRIVES; drive++)
{
accelerations[drive] = normalAccelerations[drive];
if (drive >= numAxes || !doMotorMapping)
{
endPoint[drive] = Move::MotorEndPointToMachine(drive, nextMove.coords[drive]);
}
endCoordinates[drive] = nextMove.coords[drive];
const int32_t delta = (drive < numAxes) ? endPoint[drive] - positionNow[drive] : endPoint[drive];
DriveMovement& dm = ddm[drive];
if (drive < numAxes && !isSpecialDeltaMove)
{
directionVector[drive] = nextMove.coords[drive] - prev->GetEndCoordinate(drive, false);
dm.state = (isDeltaMovement || delta != 0)
? DMState::moving // on a delta printer, if one tower moves then we assume they all do
: DMState::idle;
}
else
{
directionVector[drive] = (float)delta/reprap.GetPlatform()->DriveStepsPerUnit(drive);
dm.state = (delta != 0) ? DMState::moving : DMState::idle;
}
if (dm.state == DMState::moving)
{
dm.totalSteps = labs(delta); // for now this is the number of net steps, but gets adjusted later if there is a reverse in direction
dm.direction = (delta >= 0); // for now this is the direction of net movement, but gets adjusted later if it is a delta movement
realMove = true;
if (drive < numAxes && drive != Z_AXIS)
{
xyMoving = true;
}
if (drive >= numAxes && xyMoving)
{
if (delta > 0)
{
isPrintingMove = true; // we have both movement and extrusion
}
const float compensationTime = reprap.GetPlatform()->GetPressureAdvance(drive);
if (compensationTime > 0.0)
{
// Compensation causes instant velocity changes equal to acceleration * k, so we may need to limit the acceleration
accelerations[drive] = min<float>(accelerations[drive], reprap.GetPlatform()->ConfiguredInstantDv(drive)/compensationTime);
}
}
}
}
// 2. Throw it away if there's no real movement.
if (!realMove)
{
return false;
}
// 3. Store some values
endStopsToCheck = nextMove.endStopsToCheck;
canPauseAfter = nextMove.canPauseAfter;
filePos = nextMove.filePos;
usePressureAdvance = nextMove.usePressureAdvance;
hadLookaheadUnderrun = false;
// The end coordinates will be valid at the end of this move if it does not involve endstop checks and is not a special move on a delta printer
endCoordinatesValid = (endStopsToCheck == 0) && (doMotorMapping || !move->IsDeltaMode());
// 4. Normalise the direction vector and compute the amount of motion.
// If there is any XYZ movement, then we normalise it so that the total XYZ movement has unit length.
// This means that the user gets the feed rate that he asked for. It also makes the delta calculations simpler.
if (xyMoving || ddm[Z_AXIS].state == DMState::moving)
{
if (isDeltaMovement)
{
// Add on the Z movement needed to compensate for bed tilt
const DeltaParameters& dparams = move->GetDeltaParams();
directionVector[Z_AXIS] += (directionVector[X_AXIS] * dparams.GetXTilt()) + (directionVector[Y_AXIS] * dparams.GetYTilt());
}
totalDistance = Normalise(directionVector, DRIVES, numAxes);
if (isDeltaMovement)
{
// The following are only needed when doing delta movements. We could defer computing them until Prepare(), which would make simulation faster.
a2plusb2 = fsquare(directionVector[X_AXIS]) + fsquare(directionVector[Y_AXIS]);
cKc = (int32_t)(directionVector[Z_AXIS] * DriveMovement::Kc);
const float initialX = prev->GetEndCoordinate(X_AXIS, false);
const float initialY = prev->GetEndCoordinate(Y_AXIS, false);
const DeltaParameters& dparams = move->GetDeltaParams();
const float diagonalSquared = fsquare(dparams.GetDiagonal());
const float a2b2D2 = a2plusb2 * diagonalSquared;
for (size_t drive = 0; drive < DELTA_AXES; ++drive)
{
const float A = initialX - dparams.GetTowerX(drive);
const float B = initialY - dparams.GetTowerY(drive);
const float stepsPerMm = reprap.GetPlatform()->DriveStepsPerUnit(drive);
DriveMovement& dm = ddm[drive];
const float aAplusbB = A * directionVector[X_AXIS] + B * directionVector[Y_AXIS];
const float dSquaredMinusAsquaredMinusBsquared = diagonalSquared - fsquare(A) - fsquare(B);
float h0MinusZ0 = sqrtf(dSquaredMinusAsquaredMinusBsquared);
dm.mp.delta.hmz0sK = (int32_t)(h0MinusZ0 * stepsPerMm * DriveMovement::K2);
dm.mp.delta.minusAaPlusBbTimesKs = -(int32_t)(aAplusbB * stepsPerMm * DriveMovement::K2);
dm.mp.delta.dSquaredMinusAsquaredMinusBsquaredTimesKsquaredSsquared =
(int64_t)(dSquaredMinusAsquaredMinusBsquared * fsquare(stepsPerMm * DriveMovement::K2));
// Calculate the distance at which we need to reverse direction.
if (a2plusb2 <= 0.0)
{
// Pure Z movement. We can't use the main calculation because it divides by a2plusb2.
dm.direction = (directionVector[Z_AXIS] >= 0.0);
dm.reverseStartStep = dm.totalSteps + 1;
}
else
{
// The distance to reversal is the solution to a quadratic equation. One root corresponds to the carriages being above the bed,
// the other root corresponds to the carriages being above the bed.
const float drev = ((directionVector[Z_AXIS] * sqrt(a2b2D2 - fsquare(A * directionVector[Y_AXIS] - B * directionVector[X_AXIS])))
- aAplusbB)/a2plusb2;
if (drev > 0.0 && drev < totalDistance) // if the reversal point is within range
{
// Calculate how many steps we need to move up before reversing
const float hrev = directionVector[Z_AXIS] * drev + sqrt(dSquaredMinusAsquaredMinusBsquared - 2 * drev * aAplusbB - a2plusb2 * fsquare(drev));
int32_t numStepsUp = (int32_t)((hrev - h0MinusZ0) * stepsPerMm);
// We may be almost at the peak height already, in which case we don't really have a reversal.
if (numStepsUp < 1 || (dm.direction && (uint32_t)numStepsUp <= dm.totalSteps))
{
dm.reverseStartStep = dm.totalSteps + 1;
}
else
{
dm.reverseStartStep = (uint32_t)numStepsUp + 1;
// Correct the initial direction and the total number of steps
if (dm.direction)
{
// Net movement is up, so we will go up a bit and then down by a lesser amount
dm.totalSteps = (2 * numStepsUp) - dm.totalSteps;
}
else
{
// Net movement is down, so we will go up first and then down by a greater amount
dm.direction = true;
dm.totalSteps = (2 * numStepsUp) + dm.totalSteps;
}
}
}
else
{
dm.reverseStartStep = dm.totalSteps + 1;
}
}
}
}
}
else
{
totalDistance = Normalise(directionVector, DRIVES, DRIVES);
}
// 5. Compute the maximum acceleration available and maximum top speed
float normalisedDirectionVector[DRIVES]; // Used to hold a unit-length vector in the direction of motion
memcpy(normalisedDirectionVector, directionVector, sizeof(normalisedDirectionVector));
Absolute(normalisedDirectionVector, DRIVES);
acceleration = VectorBoxIntersection(normalisedDirectionVector, accelerations, DRIVES);
// Set the speed to the smaller of the requested and maximum speed.
// Also enforce a minimum speed of 0.5mm/sec. We need a minimum speed to avoid overflow in the movement calculations.
float reqSpeed = nextMove.feedRate;
if (isSpecialDeltaMove)
{
// Special case of a raw or homing move on a delta printer
// We use the Cartesian motion system to implement these moves, so the feed rate will be interpreted in Cartesian coordinates.
// This is wrong, we want the feed rate to apply to the drive that is moving the farthest.
float maxDistance = 0.0;
for (size_t axis = 0; axis < DELTA_AXES; ++axis)
{
if (normalisedDirectionVector[axis] > maxDistance)
{
maxDistance = normalisedDirectionVector[axis];
}
}
if (maxDistance != 0.0) // should always be true
{
reqSpeed /= maxDistance; // because normalisedDirectionVector is unit-normalised
}
}
requestedSpeed = max<float>(0.5, min<float>(reqSpeed, VectorBoxIntersection(normalisedDirectionVector, reprap.GetPlatform()->MaxFeedrates(), DRIVES)));
// On a Cartesian or CoreXY printer, it is OK to limit the X and Y speeds and accelerations independently, and in consequence to allow greater values
// for diagonal moves. On a delta, this is not OK and any movement in the XY plane should be limited to the X/Y axis values, which we assume to be equal.
if (isDeltaMovement)
{
const float xyFactor = sqrt(fsquare(normalisedDirectionVector[X_AXIS]) + fsquare(normalisedDirectionVector[X_AXIS]));
const float maxSpeed = reprap.GetPlatform()->MaxFeedrates()[X_AXIS];
if (requestedSpeed * xyFactor > maxSpeed)
{
requestedSpeed = maxSpeed/xyFactor;
}
const float maxAcceleration = normalAccelerations[X_AXIS];
if (acceleration * xyFactor > maxAcceleration)
{
acceleration = maxAcceleration/xyFactor;
}
}
// 6. Calculate the provisional accelerate and decelerate distances and the top speed
endSpeed = 0.0; // until the next move asks us to adjust it
if (prev->state != provisional)
{
// There is no previous move that we can adjust, so this move must start at zero speed.
startSpeed = 0.0;
}
else
{
// Try to meld this move to the previous move to avoid stop/start
// Assuming that this move ends with zero speed, calculate the maximum possible starting speed: u^2 = v^2 - 2as
prev->targetNextSpeed = min<float>(sqrtf(acceleration * totalDistance * 2.0), requestedSpeed);
DoLookahead(prev);
startSpeed = prev->targetNextSpeed;
}
RecalculateMove();
state = provisional;
return true;
}
float DDA::GetMotorPosition(size_t drive) const
{
return Move::MotorEndpointToPosition(endPoint[drive], drive);
}
// Return true if this move is or might have been intended to be a deceleration-only move
// A move planned as a deceleration-only move may have a short acceleration segment at the start because of rounding error
// We declare this inline because it is only used once, in DDA::DoLookahead
inline bool DDA::IsDecelerationMove() const
{
return decelDistance == totalDistance // the simple case - is a deceleration-only move
|| (topSpeed < requestedSpeed // can't have been intended as deceleration-only if it reaches the requested speed
&& decelDistance > 0.98 * totalDistance // rounding error can only go so far
&& prev->state == DDA::provisional // if we can't adjust the previous move then we don't care (and its figures may not be reliable if it has been recycled already)
&& prev->decelDistance > 0.0); // if the previous move has no deceleration phase then no point in adjus6ting it
}
// Try to increase the ending speed of this move to allow the next move to start at targetNextSpeed
/*static*/ void DDA::DoLookahead(DDA *laDDA)
pre(state == provisional)
{
// if (reprap.Debug(moduleDda)) debugPrintf("Adjusting, %f\n", laDDA->targetNextSpeed);
unsigned int laDepth = 0;
bool goingUp = true;
for(;;) // this loop is used to nest lookahead without making recursive calls
{
bool recurse = false;
if (goingUp)
{
// We have been asked to adjust the end speed of this move to match the next move starting at targetNextSpeed
if (laDDA->topSpeed >= laDDA->requestedSpeed)
{
// This move already reaches its top speed, so just need to adjust the deceleration part
laDDA->endSpeed = laDDA->requestedSpeed; // remove the deceleration phase
laDDA->CalcNewSpeeds(); // put it back if necessary
}
else if (laDDA->IsDecelerationMove())
{
// This is a deceleration-only move, so we may have to adjust the previous move as well to get optimum behaviour
if (laDDA->prev->state == provisional)
{
laDDA->endSpeed = laDDA->requestedSpeed;
laDDA->CalcNewSpeeds();
const float maxStartSpeed = sqrtf(fsquare(laDDA->endSpeed) + (2 * laDDA->acceleration * laDDA->totalDistance));
if (maxStartSpeed < laDDA->requestedSpeed)
{
laDDA->prev->targetNextSpeed = maxStartSpeed;
// Still provisionally a decelerate-only move
}
else
{
laDDA->prev->targetNextSpeed = laDDA->requestedSpeed;
}
recurse = true;
}
else
{
// This move is a deceleration-only move but we can't adjust the previous one
laDDA->hadLookaheadUnderrun = true;
laDDA->endSpeed = min<float>(sqrtf(fsquare(laDDA->startSpeed) + (2 * laDDA->acceleration * laDDA->totalDistance)),
laDDA->requestedSpeed);
laDDA->CalcNewSpeeds();
}
}
else
{
// This move doesn't reach its requested speed, but it isn't a deceleration-only move
// Set its end speed to the minimum of the requested speed and the highest we can reach
laDDA->endSpeed = min<float>(sqrtf(fsquare(laDDA->startSpeed) + (2 * laDDA->acceleration * laDDA->totalDistance)),
laDDA->requestedSpeed);
laDDA->CalcNewSpeeds();
}
}
else
{
// Going back down the list
// We have adjusted the end speed of the previous move as much as is possible and it has adjusted its targetNextSpeed accordingly.
// Adjust this move to match it.
laDDA->startSpeed = laDDA->prev->targetNextSpeed;
const float maxEndSpeed = sqrtf(fsquare(laDDA->startSpeed) + (2 * laDDA->acceleration * laDDA->totalDistance));
if (maxEndSpeed < laDDA->endSpeed)
{
// Oh dear, we were too optimistic! Have another go.
laDDA->endSpeed = maxEndSpeed;
laDDA->CalcNewSpeeds();
}
}
if (recurse)
{
// Still going up
laDDA = laDDA->prev;
++laDepth;
if (reprap.Debug(moduleDda)) debugPrintf("Recursion start %u\n", laDepth);
}
else
{
// Either just stopped going up. or going down
laDDA->RecalculateMove();
if (laDepth == 0)
{
// if (reprap.Debug(moduleDda)) debugPrintf("Complete, %f\n", laDDA->targetNextSpeed);
return;
}
laDDA = laDDA->next;
--laDepth;
goingUp = false;
}
}
}
// Recalculate the top speed, acceleration distance and deceleration distance, and whether we can pause after this move
// This may cause a move that we intended to be a deceleration-only move to have a tiny acceleration segment at the start
void DDA::RecalculateMove()
{
accelDistance = (fsquare(requestedSpeed) - fsquare(startSpeed))/(2.0 * acceleration);
decelDistance = (fsquare(requestedSpeed) - fsquare(endSpeed))/(2.0 * acceleration);
if (accelDistance + decelDistance >= totalDistance)
{
// This move has no steady-speed phase, so it's accelerate-decelerate or accelerate-only move.
// If V is the peak speed, then (V^2 - u^2)/2a + (V^2 - v^2)/2a = distance.
// So (2V^2 - u^2 - v^2)/2a = distance
// So V^2 = a * distance + 0.5(u^2 + v^2)
float vsquared = (acceleration * totalDistance) + 0.5 * (fsquare(startSpeed) + fsquare(endSpeed));
// Calculate accelerate distance from: V^2 = u^2 + 2as
if (vsquared >= 0.0)
{
accelDistance = max<float>((vsquared - fsquare(startSpeed))/(2.0 * acceleration), 0.0);
decelDistance = totalDistance - accelDistance;
topSpeed = sqrtf(vsquared);
}
else if (startSpeed < endSpeed)
{
// This would ideally never happen, but might because of rounding errors
accelDistance = totalDistance;
decelDistance = 0.0;
topSpeed = endSpeed;
}
else
{
// This would ideally never happen, but might because of rounding errors
accelDistance = 0.0;
decelDistance = totalDistance;
topSpeed = startSpeed;
}
}
else
{
topSpeed = requestedSpeed;
}
if (canPauseAfter && endSpeed != 0.0)
{
const Platform * const p = reprap.GetPlatform();
for (size_t drive = 0; drive < DRIVES; ++drive)
{
if (ddm[drive].state == DMState::moving && endSpeed * fabsf(directionVector[drive]) > p->ActualInstantDv(drive))
{
canPauseAfter = false;
break;
}
}
}
}
// Decide what speed we would really like this move to end at.
// On entry, endSpeed is our proposed ending speed and targetNextSpeed is the proposed starting speed of the next move
// On return, targetNextSpeed is the speed we would like the next move to start at, and endSpeed is the corresponding end speed of this move.
void DDA::CalcNewSpeeds()
{
// We may have to make multiple passes, because reducing one of the speeds may solve some problems but actually make matters worse on another axis.
bool limited;
do
{
// debugPrintf(" Pass, start=%f end=%f\n", targetStartSpeed, endSpeed);
limited = false;
for (size_t drive = 0; drive < DRIVES; ++drive)
{
const float thisMoveFraction = directionVector[drive];
const float nextMoveFraction = next->directionVector[drive];
const DriveMovement& thisMoveDm = ddm[drive];
const DriveMovement& nextMoveDm = next->ddm[drive];
if (thisMoveDm.state == DMState::moving || nextMoveDm.state == DMState::moving)
{
const float thisMoveSpeed = endSpeed * thisMoveFraction;
const float nextMoveSpeed = targetNextSpeed * nextMoveFraction;
const float idealDeltaV = fabsf(thisMoveSpeed - nextMoveSpeed);
float maxDeltaV = reprap.GetPlatform()->ActualInstantDv(drive);
if (idealDeltaV > maxDeltaV)
{
// This drive can't change speed fast enough, so reduce the start and/or end speeds
// This algorithm sometimes converges very slowly, requiring many passes.
// To ensure it converges at all, and to speed up convergence, we over-adjust the speed to achieve an even lower deltaV.
maxDeltaV *= 0.8;
if ((thisMoveFraction >= 0.0) == (nextMoveFraction >= 0.0))
{
// Drive moving in the same direction for this move and the next one, so we must reduce speed of the faster one
if (fabsf(thisMoveSpeed) > fabsf(nextMoveSpeed))
{
endSpeed = (fabsf(nextMoveSpeed) + maxDeltaV)/fabsf(thisMoveFraction);
}
else
{
targetNextSpeed = (fabsf(thisMoveSpeed) + maxDeltaV)/fabsf(nextMoveFraction);
}
}
else if (fabsf(thisMoveSpeed) * 2 < maxDeltaV)
{
targetNextSpeed = (maxDeltaV - fabsf(thisMoveSpeed))/fabsf(nextMoveFraction);
}
else if (fabsf(nextMoveSpeed) * 2 < maxDeltaV)
{
endSpeed = (maxDeltaV - fabsf(nextMoveSpeed))/fabsf(thisMoveFraction);
}
else
{
targetNextSpeed = maxDeltaV/(2 * fabsf(nextMoveFraction));
endSpeed = maxDeltaV/(2 * fabsf(thisMoveFraction));
}
limited = true;
// Most conflicts are between X and Y. So if we just did Y, start another pass immediately to save time.
if (drive == 1)
{
break;
}
}
}
}
} while (limited);
}
// This is called by Move::CurrentMoveCompleted to update the live coordinates from the move that has just finished
bool DDA::FetchEndPosition(volatile int32_t ep[DRIVES], volatile float endCoords[DRIVES])
{
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
for (size_t drive = 0; drive < DRIVES; ++drive)
{
ep[drive] = endPoint[drive];
}
if (endCoordinatesValid)
{
for (size_t axis = 0; axis < numAxes; ++axis)
{
endCoords[axis] = endCoordinates[axis];
}
}
// Extrusion amounts are always valid
for (size_t eDrive = numAxes; eDrive < DRIVES; ++eDrive)
{
endCoords[eDrive] += endCoordinates[eDrive];
}
return endCoordinatesValid;
}
void DDA::SetPositions(const float move[DRIVES], size_t numDrives)
{
reprap.GetMove()->EndPointToMachine(move, endPoint, numDrives);
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
for (size_t axis = 0; axis < numAxes; ++axis)
{
endCoordinates[axis] = move[axis];
}
endCoordinatesValid = true;
}
// Get a Cartesian end coordinate from this move
float DDA::GetEndCoordinate(size_t drive, bool disableDeltaMapping)
pre(disableDeltaMapping || drive < MAX_AXES)
{
if (disableDeltaMapping)
{
return Move::MotorEndpointToPosition(endPoint[drive], drive);
}
else
{
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
if (drive < numAxes && !endCoordinatesValid)
{
reprap.GetMove()->MachineToEndPoint(endPoint, endCoordinates, numAxes);
endCoordinatesValid = true;
}
return endCoordinates[drive];
}
}
// Calculate the time needed for this move. Called instead of Prepare when we are in simulation mode.
float DDA::CalcTime() const
{
return (topSpeed - startSpeed)/acceleration // acceleration time
+ (totalDistance - accelDistance - decelDistance)/topSpeed // steady speed time
+ (topSpeed - endSpeed)/acceleration; // deceleration time
}
// Prepare this DDA for execution.
// This must not be called with interrupts disabled, because it calls Platform::EnableDrive.
void DDA::Prepare()
{
//debugPrintf("Prep\n");
PrepParams params;
params.decelStartDistance = totalDistance - decelDistance;
// Convert the accelerate/decelerate distances to times
float accelStopTime = (topSpeed - startSpeed)/acceleration;
float decelStartTime = accelStopTime + (params.decelStartDistance - accelDistance)/topSpeed;
float totalTime = decelStartTime + (topSpeed - endSpeed)/acceleration;
clocksNeeded = (uint32_t)(totalTime * stepClockRate);
params.startSpeedTimesCdivA = (uint32_t)((startSpeed * stepClockRate)/acceleration);
params.topSpeedTimesCdivA = (uint32_t)((topSpeed * stepClockRate)/acceleration);
params.decelStartClocks = (uint32_t)(decelStartTime * stepClockRate);
params.topSpeedTimesCdivAPlusDecelStartClocks = params.topSpeedTimesCdivA + params.decelStartClocks;
params.accelClocksMinusAccelDistanceTimesCdivTopSpeed = (uint32_t)((accelStopTime - (accelDistance/topSpeed)) * stepClockRate);
params.compFactor = 1.0 - startSpeed/topSpeed;
goingSlow = false;
firstDM = nullptr;
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
for (size_t drive = 0; drive < DRIVES; ++drive)
{
DriveMovement& dm = ddm[drive];
if (dm.state == DMState::moving)
{
dm.drive = drive;
reprap.GetPlatform()->EnableDrive(drive);
if (drive >= numAxes)
{
dm.PrepareExtruder(*this, params, usePressureAdvance);
// Check for sensible values, print them if they look dubious
if (reprap.Debug(moduleDda)
&& ( dm.totalSteps > 1000000
|| dm.reverseStartStep < dm.mp.cart.decelStartStep
|| (dm.reverseStartStep <= dm.totalSteps
&& dm.mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA > (int64_t)(dm.mp.cart.twoCsquaredTimesMmPerStepDivA * dm.reverseStartStep))
)
)
{
DebugPrint();
}
}
else if (isDeltaMovement)
{
dm.PrepareDeltaAxis(*this, params);
// Check for sensible values, print them if they look dubious
if (reprap.Debug(moduleDda) && dm.totalSteps > 1000000)
{
DebugPrint();
}
}
else
{
dm.PrepareCartesianAxis(*this, params);
// Check for sensible values, print them if they look dubious
if (reprap.Debug(moduleDda) && dm.totalSteps > 1000000)
{
DebugPrint();
}
}
// Prepare for the first step
dm.nextStep = 0;
dm.nextStepTime = 0;
dm.stepInterval = 999999; // initialise to a large value so that we will calculate the time for just one step
dm.stepsTillRecalc = 0; // so that we don't skip the calculation
bool stepsToDo = (isDeltaMovement && drive < numAxes)
? dm.CalcNextStepTimeDelta(*this, false)
: dm.CalcNextStepTimeCartesian(*this, false);
if (stepsToDo)
{
InsertDM(&dm);
}
else
{
dm.state = DMState::idle;
}
}
}
if (reprap.Debug(moduleDda) && reprap.Debug(moduleMove)) // temp show the prepared DDA if debug enabled for both modules
{
DebugPrint();
}
#if DDA_MOVE_DEBUG
MoveParameters& m = savedMoves[savedMovePointer];
m.accelDistance = accelDistance;
m.decelDistance = decelDistance;
m.steadyDistance = totalDistance - accelDistance - decelDistance;
m.startSpeed = startSpeed;
m.topSpeed = topSpeed;
m.endSpeed = endSpeed;
savedMovePointer = (savedMovePointer + 1) % NumSavedMoves;
#endif
state = frozen; // must do this last so that the ISR doesn't start executing it before we have finished setting it up
}
// Take a unit positive-hyperquadrant vector, and return the factor needed to obtain
// length of the vector as projected to touch box[].
float DDA::VectorBoxIntersection(const float v[], const float box[], size_t dimensions)
{
// Generate a vector length that is guaranteed to exceed the size of the box
float biggerThanBoxDiagonal = 2.0*Magnitude(box, dimensions);
float magnitude = biggerThanBoxDiagonal;
for (size_t d = 0; d < dimensions; d++)
{
if (biggerThanBoxDiagonal*v[d] > box[d])
{
float a = box[d]/v[d];
if (a < magnitude)
{
magnitude = a;
}
}
}
return magnitude;
}
// Normalise a vector with dim1 dimensions so that it is unit in the first dim2 dimensions, and also return its previous magnitude in dim2 dimensions
float DDA::Normalise(float v[], size_t dim1, size_t dim2)
{
float magnitude = Magnitude(v, dim2);
if (magnitude <= 0.0)
{
return 0.0;
}
Scale(v, 1.0/magnitude, dim1);
return magnitude;
}
// Return the magnitude of a vector
float DDA::Magnitude(const float v[], size_t dimensions)
{
float magnitude = 0.0;
for (size_t d = 0; d < dimensions; d++)
{
magnitude += v[d]*v[d];
}
magnitude = sqrtf(magnitude);
return magnitude;
}
// Multiply a vector by a scalar
void DDA::Scale(float v[], float scale, size_t dimensions)
{
for(size_t d = 0; d < dimensions; d++)
{
v[d] = scale*v[d];
}
}
// Move a vector into the positive hyperquadrant
void DDA::Absolute(float v[], size_t dimensions)
{
for(size_t d = 0; d < dimensions; d++)
{
v[d] = fabsf(v[d]);
}
}
// The remaining functions are speed-critical, so use full optimisation
#pragma GCC optimize ("O3")
// Start executing this move, returning true if Step() needs to be called immediately. Must be called with interrupts disabled, to avoid a race condition.
// Returns true if the caller needs to call the step ISR immediately.
bool DDA::Start(uint32_t tim)
pre(state == frozen)
{
moveStartTime = tim;
state = executing;
#if DDA_LOG_PROBE_CHANGES
if ((endStopsToCheck & LogProbeChanges) != 0)
{
numLoggedProbePositions = 0;
probeTriggered = false;
}
#endif
if (firstDM != nullptr)
{
unsigned int extrusions = 0, retractions = 0; // bitmaps of extruding and retracting drives
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
for (size_t i = 0; i < DRIVES; ++i)
{
DriveMovement& dm = ddm[i];
if (dm.state == DMState::moving)
{
reprap.GetPlatform()->SetDirection(i, dm.direction);
if (i >= numAxes)
{
if (dm.direction == FORWARDS)
{
extrusions |= (1 << (i - numAxes));
}
else
{
retractions |= (1 << (i - numAxes));
}
}
}
}
bool extruding = false;
if (extrusions != 0 || retractions != 0)
{
const unsigned int prohibitedMovements = reprap.GetProhibitedExtruderMovements(extrusions, retractions);
for (DriveMovement **dmpp = &firstDM; *dmpp != nullptr; )
{
bool thisDriveExtruding = (*dmpp)->drive >= numAxes;
if (thisDriveExtruding && (prohibitedMovements & (1 << ((*dmpp)->drive - numAxes))) != 0)
{
*dmpp = (*dmpp)->nextDM;
}
else
{
extruding = extruding || thisDriveExtruding;
dmpp = &((*dmpp)->nextDM);
}
}
}
Platform * const platform = reprap.GetPlatform();
if (extruding)
{
platform->ExtrudeOn();
}
else
{
platform->ExtrudeOff();
}
if (firstDM != nullptr)
{
return platform->ScheduleInterrupt(firstDM->nextStepTime + moveStartTime);
}
}
// No steps are pending. This should not happen, except perhaps for an extrude-only move when extrusion is prohibited
return true; // schedule another interrupt immediately
}
extern uint32_t maxReps;
// This is called by the interrupt service routine to execute steps.
// It returns true if it needs to be called again on the DDA of the new current move, otherwise false.
// This must be as fast as possible, because it determines the maximum movement speed.
bool DDA::Step()
{
Platform * const platform = reprap.GetPlatform();
uint32_t lastStepPulseTime = platform->GetInterruptClocks();
bool repeat;
uint32_t numReps = 0;
do
{
// Keep this loop as fast as possible, in the case that there are no endstops to check!
// 1. Check endstop switches and Z probe if asked. This is not speed critical because fast moves do not use endstops or the Z probe.
if (endStopsToCheck != 0) // if any homing switches or the Z probe is enabled in this move
{
if ((endStopsToCheck & ZProbeActive) != 0) // if the Z probe is enabled in this move
{
// Check whether the Z probe has been triggered. On a delta at least, this must be done separately from endstop checks,
// because we have both a high endstop and a Z probe, and the Z motor is not the same thing as the Z axis.
switch (platform->GetZProbeResult())
{
case EndStopHit::lowHit:
MoveAborted(); // set the state to completed and recalculate the endpoints
reprap.GetMove()->ZProbeTriggered(this);
break;
case EndStopHit::lowNear:
ReduceHomingSpeed();
break;
default:
break;
}
}
#if DDA_LOG_PROBE_CHANGES
else if ((endStopsToCheck & LogProbeChanges) != 0)
{
switch (platform->GetZProbeResult())
{
case EndStopHit::lowHit:
if (!probeTriggered)
{
probeTriggered = true;
LogProbePosition();
}
break;
case EndStopHit::lowNear:
case EndStopHit::noStop:
if (probeTriggered)
{
probeTriggered = false;
LogProbePosition();
}
break;
default:
break;
}
}
#endif
const size_t numAxes = reprap.GetGCodes()->GetNumAxes();
for (size_t drive = 0; drive < numAxes; ++drive)
{
if ((endStopsToCheck & (1 << drive)) != 0)
{
switch(platform->Stopped(drive))
{
case EndStopHit::lowHit:
endStopsToCheck &= ~(1 << drive); // clear this check so that we can check for more
if (endStopsToCheck == 0 || reprap.GetMove()->IsCoreXYAxis(drive)) // if no more endstops to check, or this axis uses shared motors
{
MoveAborted();
}
else
{
StopDrive(drive);
}
reprap.GetMove()->HitLowStop(drive, this);
break;
case EndStopHit::highHit:
endStopsToCheck &= ~(1 << drive); // clear this check so that we can check for more
if (endStopsToCheck == 0 || reprap.GetMove()->IsCoreXYAxis(drive)) // if no more endstops to check, or this axis uses shared motors
{
MoveAborted();
}
else
{
StopDrive(drive);
}
reprap.GetMove()->HitHighStop(drive, this);
break;
case EndStopHit::lowNear:
// Only reduce homing speed if there are no more axes to be homed.
// This allows us to home X and Y simultaneously.
if (endStopsToCheck == (1 << drive))
{
ReduceHomingSpeed();
}
break;
default:
break;
}
}
}
if (state == completed) // we may have completed the move due to triggering an endstop switch or Z probe
{
break;
}
}
// 2. Determine which drivers are due for stepping, overdue, or will be due very shortly
DriveMovement* dm = firstDM;
const uint32_t elapsedTime = (Platform::GetInterruptClocks() - moveStartTime) + minInterruptInterval;
uint32_t driversStepping = 0;
while (dm != nullptr && elapsedTime >= dm->nextStepTime) // if the next step is due
{
++numReps;
driversStepping |= platform->GetDriversBitmap(dm->drive);
dm = dm->nextDM;
//uint32_t t3 = Platform::GetInterruptClocks() - t2;
//if (t3 > maxCalcTime) maxCalcTime = t3;
//if (t3 < minCalcTime) minCalcTime = t3;
}
// 3. Step the drivers
if ((driversStepping & platform->GetSlowDrivers()) != 0)
{
while (Platform::GetInterruptClocks() - lastStepPulseTime < platform->GetSlowDriverClocks()) {}
Platform::StepDriversHigh(driversStepping); // generate the steps
lastStepPulseTime = Platform::GetInterruptClocks();
}
else
{
Platform::StepDriversHigh(driversStepping); // generate the steps
}
// 4. Remove those drives from the list, calculate the next step times, update the direction pins where necessary,
// and re-insert them so as to keep the list in step-time order. We assume that meeting the direction pin hold time
// is not a problem for any driver type. This is not necessarily true.
DriveMovement *dmToInsert = firstDM; // head of the chain we need to re-insert
firstDM = dm; // remove the chain from the list
while (dmToInsert != dm) // note that both of these may be nullptr
{
const bool hasMoreSteps = (isDeltaMovement && dmToInsert->drive < DELTA_AXES)
? dmToInsert->CalcNextStepTimeDelta(*this, true)
: dmToInsert->CalcNextStepTimeCartesian(*this, true);
DriveMovement * const nextToInsert = dmToInsert->nextDM;
if (hasMoreSteps)
{
InsertDM(dmToInsert);
}
dmToInsert = nextToInsert;
}
// 5. Reset all step pins low
if ((driversStepping & platform->GetSlowDrivers()) != 0)
{
while (Platform::GetInterruptClocks() - lastStepPulseTime < platform->GetSlowDriverClocks()) {}
Platform::StepDriversLow(); // set all step pins low
lastStepPulseTime = Platform::GetInterruptClocks();
}
else
{
Platform::StepDriversLow(); // set all step pins low
}
// 6. Check for move completed
if (firstDM == nullptr)
{
state = completed;
break;
}
// 7. Schedule next interrupt, or if it would be too soon, generate more steps immediately
repeat = platform->ScheduleInterrupt(firstDM->nextStepTime + moveStartTime);
} while (repeat);
if (numReps > maxReps)
{
maxReps = numReps;
}
if (state == completed)
{
uint32_t finishTime = moveStartTime + clocksNeeded; // calculate how long this move should take
Move *move = reprap.GetMove();
move->CurrentMoveCompleted(); // tell Move that the current move is complete
return move->TryStartNextMove(finishTime); // schedule the next move
}
return false;
}
// Stop a drive and re-calculate the corresponding endpoint
void DDA::StopDrive(size_t drive)
{
DriveMovement& dm = ddm[drive];
if (dm.state == DMState::moving)
{
endPoint[drive] -= dm.GetNetStepsLeft();
dm.state = DMState::idle;
if (drive < reprap.GetGCodes()->GetNumAxes())
{
endCoordinatesValid = false; // the XYZ position is no longer valid
}
RemoveDM(drive);
if (firstDM == nullptr)
{
state = completed;
}
}
}
// This is called when we abort a move because we have hit an endstop.
// It adjusts the end points of the current move to account for how far through the move we got.
void DDA::MoveAborted()
{
for (size_t drive = 0; drive < DRIVES; ++drive)
{
StopDrive(drive);
}
state = completed;
}
// Reduce the speed of this move to the indicated speed.
// This is called from the ISR, so interrupts are disabled and nothing else can mess with us.
// As this is only called for homing moves and with very low speeds, we assume that we don't need acceleration or deceleration phases.
void DDA::ReduceHomingSpeed()
{
if (!goingSlow)
{
goingSlow = true;
const float factor = 3.0; // the factor by which we are reducing the speed
topSpeed /= factor;
for (size_t drive = 0; drive < DRIVES; ++drive)
{
DriveMovement& dm = ddm[drive];
if (dm.state == DMState::moving)
{
dm.ReduceSpeed(*this, factor);
RemoveDM(dm.drive);
InsertDM(&dm);
}
}
// We also need to adjust the total clocks needed, to prevent step errors being recorded
const uint32_t clocksSoFar = Platform::GetInterruptClocks() - moveStartTime;
if (clocksSoFar < clocksNeeded)
{
const uint32_t clocksLeft = clocksNeeded - clocksSoFar;
clocksNeeded += (uint32_t)(clocksLeft * (factor - 1.0));
}
}
}
bool DDA::HasStepError() const
{
for (size_t drive = 0; drive < DRIVES; ++drive)
{
const DriveMovement& dm = ddm[drive];
if (dm.state == DMState::stepError)
{
return true;
}
}
return false;
}
// Remove this drive from the list of drives with steps due, and return its DM or nullptr if not there
// Called from the step ISR only.
DriveMovement *DDA::RemoveDM(size_t drive)
{
DriveMovement **dmp = &firstDM;
while (*dmp != nullptr)
{
DriveMovement *dm = *dmp;
if (dm->drive == drive)
{
(*dmp) = dm->nextDM;
return dm;
}
dmp = &(dm->nextDM);
}
return nullptr;
}
// End
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