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Current position array removed - now all handled by the look ahead ring.

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This commit is contained in:
Adrian Bowyer 2013-06-12 22:37:33 +01:00
parent 21c22a3aef
commit db890d6157
7 changed files with 336 additions and 85 deletions
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31
Move.h
View file

@ -77,7 +77,7 @@ class LookAhead
boolean checkEndStops;
float cosine;
float v;
int8_t processed;
volatile int8_t processed;
};
@ -97,6 +97,7 @@ class DDA
Move* move;
Platform* platform;
DDA* next;
LookAhead* myLookAheadEntry;
long counter[DRIVES];
long delta[DRIVES];
boolean directions[DRIVES];
@ -131,8 +132,8 @@ class Move
boolean AllMovesAreFinished();
void ResumeMoving();
void DoLookAhead();
void HitLowStop(int8_t drive);
void HitHighStop(int8_t drive);
void HitLowStop(int8_t drive, LookAhead* la);
void HitHighStop(int8_t drive, LookAhead* la);
friend class DDA;
@ -162,7 +163,7 @@ class Move
LookAhead* lookAheadRingAddPointer;
LookAhead* lookAheadRingGetPointer;
//LookAhead* larWaiting;
LookAhead* lastMove;
DDA* lookAheadDDA;
int lookAheadRingCount;
@ -171,7 +172,6 @@ class Move
boolean active;
boolean checkEndStopsOnNextMove;
float currentFeedrate;
float currentPosition[AXES]; // Note - drives above AXES are always relative moves
float nextMove[DRIVES + 1]; // Extra is for feedrate
float stepDistances[(1<<AXES)]; // Index bits: lsb -> dx, dy, dz <- msb
float extruderStepDistances[(1<<(DRIVES-AXES))]; // NB - limits us to 5 extruders
@ -213,15 +213,15 @@ inline int8_t LookAhead::Processed()
inline void LookAhead::SetProcessed(MovementState ms)
{
if(ms == 0)
processed = 0;
if(ms == unprocessed)
processed = unprocessed;
else
processed |= ms;
}
inline void LookAhead::Release()
{
processed = released;
SetProcessed(released);
}
inline boolean LookAhead::CheckEndStops()
@ -232,6 +232,7 @@ inline boolean LookAhead::CheckEndStops()
inline void LookAhead::SetDriveZeroEndSpeed(float a, int8_t drive)
{
endPoint[drive] = a;
cosine = 2.0;
v = 0.0;
}
@ -278,7 +279,9 @@ inline boolean Move::LookAheadRingEmpty()
inline boolean Move::LookAheadRingFull()
{
return lookAheadRingAddPointer->Next()->Next() == lookAheadRingGetPointer;
if(!(lookAheadRingAddPointer->Processed() & released))
return true;
return lookAheadRingAddPointer->Next()->Next() == lookAheadRingGetPointer; // probably not needed; just return the boolean in the if above
}
inline boolean Move::GetDDARingLock()
@ -311,16 +314,14 @@ inline void Move::ResumeMoving()
addNoMoreMoves = false;
}
inline void Move::HitLowStop(int8_t drive)
inline void Move::HitLowStop(int8_t drive, LookAhead* la)
{
currentPosition[drive] = 0.0;
lookAheadRingGetPointer->Previous()->SetDriveZeroEndSpeed(0.0, drive);
la->SetDriveZeroEndSpeed(0.0, drive);
}
inline void Move::HitHighStop(int8_t drive)
inline void Move::HitHighStop(int8_t drive, LookAhead* la)
{
currentPosition[drive] = platform->AxisLength(drive);
lookAheadRingGetPointer->Previous()->SetDriveZeroEndSpeed(currentPosition[drive], drive);
la->SetDriveZeroEndSpeed(platform->AxisLength(drive), drive);
}

81
Move.ino
View file

@ -45,7 +45,7 @@ Move::Move(Platform* p, GCodes* g)
lookAheadRingGetPointer = new LookAhead(this, platform, lookAheadRingGetPointer);
lookAheadRingAddPointer->next = lookAheadRingGetPointer;
// Set the backwards pointers and flag them all as free
// Set the backwards pointers
lookAheadRingGetPointer = lookAheadRingAddPointer;
for(i = 0; i <= LOOK_AHEAD_RING_LENGTH; i++)
@ -66,12 +66,6 @@ void Move::Init()
for(i = 0; i < DRIVES; i++)
platform->SetDirection(i, FORWARDS);
// Set the current position to the origin
for(i = 0; i <= AXES; i++)
currentPosition[i] = 0.0;
currentFeedrate = START_FEED_RATE;
// Empty the rings
ddaRingGetPointer = ddaRingAddPointer;
@ -91,9 +85,12 @@ void Move::Init()
// Put the origin on the lookahead ring with zero velocity in the previous
// position to the first one that will be used.
lastMove = lookAheadRingAddPointer->Previous();
for(i = 0; i < DRIVES; i++)
lookAheadRingGetPointer->Previous()->SetDriveZeroEndSpeed(0.0, i);
lookAheadRingGetPointer->Previous()->SetDriveZeroEndSpeed(currentFeedrate, DRIVES);
lastMove->SetDriveZeroEndSpeed(0.0, i);
lastMove->SetDriveZeroEndSpeed(START_FEED_RATE, DRIVES);
checkEndStopsOnNextMove = false;
@ -138,8 +135,8 @@ void Move::Init()
stepDistances[0] = 1.0/platform->DriveStepsPerUnit(AXES);
extruderStepDistances[0] = stepDistances[0];
currentFeedrate = -1.0;
currentFeedrate = START_FEED_RATE;
lastTime = platform->Time();
active = true;
}
@ -171,19 +168,20 @@ void Move::Spin()
if(gCodes->ReadMove(nextMove, checkEndStopsOnNextMove))
{
if(GetMovementType(currentPosition, nextMove) == noMove)
{
currentFeedrate = nextMove[DRIVES]; // Might be G1 with just an F field
currentFeedrate = nextMove[DRIVES]; // Might be G1 with just an F field
if(GetMovementType(lastMove->EndPoint(), nextMove) == noMove) // Throw it away if there's no real movement.
return;
}
currentFeedrate = -1.0; // Real move - record its feedrate with it, not here.
if(!LookAheadRingAdd(nextMove, 0.0, checkEndStopsOnNextMove))
platform->Message(HOST_MESSAGE, "Can't add to non-full look ahead ring!\n"); // Should never happen...
for(int8_t i = 0; i < AXES; i++)
currentPosition[i] = nextMove[i];
currentFeedrate = nextMove[DRIVES];
}
}
// This returns false if it is not possible
// to use the result as the basis for the
// next move because the look ahead ring
// is full. True otherwise.
boolean Move::GetCurrentState(float m[])
{
if(LookAheadRingFull())
@ -192,11 +190,15 @@ boolean Move::GetCurrentState(float m[])
for(int8_t i = 0; i < DRIVES; i++)
{
if(i < AXES)
m[i] = currentPosition[i];
m[i] = lastMove->EndPoint()[i];
else
m[i] = 0.0;
}
m[DRIVES] = currentFeedrate;
if(currentFeedrate >= 0.0)
m[DRIVES] = currentFeedrate;
else
m[DRIVES] = lastMove->EndPoint()[DRIVES];
currentFeedrate = -1.0;
return true;
}
@ -233,9 +235,9 @@ boolean Move::DDARingAdd(LookAhead* lookAhead)
ReleaseDDARingLock();
return false;
}
if(ddaRingAddPointer->Active())
if(ddaRingAddPointer->Active()) // Should never happen...
{
platform->Message(HOST_MESSAGE, "Attempt to alter an active ring buffer entry!\n"); // Should never happen...
platform->Message(HOST_MESSAGE, "Attempt to alter an active ring buffer entry!\n");
ReleaseDDARingLock();
return false;
}
@ -283,7 +285,7 @@ void Move::DoLookAhead()
float u, v;
if(addNoMoreMoves || !gCodes->PrintingAFile() || lookAheadRingCount > LOOK_AHEAD)
/* if(addNoMoreMoves || !gCodes->PrintingAFile() || lookAheadRingCount > LOOK_AHEAD)
{
n1 = lookAheadRingGetPointer;
n0 = n1->Previous();
@ -330,7 +332,7 @@ void Move::DoLookAhead()
}while(n0 != lookAheadRingGetPointer);
n0->SetProcessed(complete);
}
*/
if(addNoMoreMoves || !gCodes->PrintingAFile() || lookAheadRingCount > 1)
{
n1 = lookAheadRingGetPointer;
@ -340,8 +342,8 @@ void Move::DoLookAhead()
{
if(n1->Processed() == unprocessed)
{
float c = n1->Cosine();
c = n1->EndPoint()[DRIVES]*c;
float c = fmin(n1->EndPoint()[DRIVES], n2->EndPoint()[DRIVES]);
c = c*n1->Cosine();
if(c <= 0)
{
int8_t mt = GetMovementType(n0->EndPoint(), n1->EndPoint());
@ -353,7 +355,8 @@ void Move::DoLookAhead()
c = platform->InstantDv(AXES); // value for first extruder - slight hack
}
n1->SetV(c);
n1->SetProcessed(vCosineSet);
//n1->SetProcessed(vCosineSet);
n1->SetProcessed(complete);
}
n0 = n1;
n1 = n2;
@ -403,7 +406,10 @@ boolean Move::LookAheadRingAdd(float ep[], float vv, boolean ce)
{
if(LookAheadRingFull())
return false;
if(!(lookAheadRingAddPointer->Processed() & released))
platform->Message(HOST_MESSAGE, "Attempt to alter a non-released lookahead ring entry!\n"); // Should never happen...
lookAheadRingAddPointer->Init(ep, vv, ce);
lastMove = lookAheadRingAddPointer;
lookAheadRingAddPointer = lookAheadRingAddPointer->Next();
lookAheadRingCount++;
return true;
@ -511,14 +517,15 @@ MovementProfile DDA::Init(LookAhead* lookAhead, float& u, float& v)
{
int8_t drive;
active = false;
myLookAheadEntry = lookAhead;
MovementProfile result = moving;
totalSteps = -1;
distance = 0.0; // X+Y+Z
float eDistance = 0.0;
float d;
float* targetPosition = lookAhead->EndPoint();
float* targetPosition = myLookAheadEntry->EndPoint();
v = lookAhead->V();
float* positionNow = lookAhead->Previous()->EndPoint();
float* positionNow = myLookAheadEntry->Previous()->EndPoint();
u = lookAhead->Previous()->V();
checkEndStops = lookAhead->CheckEndStops();
@ -554,13 +561,12 @@ MovementProfile DDA::Init(LookAhead* lookAhead, float& u, float& v)
if(totalSteps <= 0)
{
platform->Message(HOST_MESSAGE, "DDA.Init(): Null movement!\n");
myLookAheadEntry->Release();
return result;
}
// Set up the DDA
result = moving;
counter[0] = -totalSteps/2;
for(drive = 1; drive < DRIVES; drive++)
counter[drive] = counter[0];
@ -685,8 +691,6 @@ MovementProfile DDA::Init(LookAhead* lookAhead, float& u, float& v)
timeStep = timeStep/velocity;
lookAhead->Release();
return result;
}
@ -729,12 +733,12 @@ void DDA::Step(boolean noTest)
EndStopHit esh = platform->Stopped(drive);
if(esh == lowHit)
{
move->HitLowStop(drive);
move->HitLowStop(drive, myLookAheadEntry);
active = false;
}
if(esh == highHit)
{
move->HitHighStop(drive);
move->HitHighStop(drive, myLookAheadEntry);
active = false;
}
}
@ -758,15 +762,18 @@ void DDA::Step(boolean noTest)
if(stepCount >= startDStep)
velocity -= acceleration*timeStep;
if(noTest)
platform->SetInterrupt((long)(1.0e6*timeStep));
stepCount++;
active = stepCount < totalSteps;
if(noTest)
platform->SetInterrupt((long)(1.0e6*timeStep));
}
if(!active && noTest)
{
myLookAheadEntry->Release();
platform->SetInterrupt(STANDBY_INTERRUPT_RATE);
}
}
//***************************************************************************************************

4
Platform.h
View file

@ -77,8 +77,8 @@ Licence: GPL
#define HIGH_STOP_PINS {-1, -1, -1, -1}
#define ENDSTOP_HIT 1 // when a stop == this it is hit
#define MAX_FEEDRATES {300, 300, 3, 45} // mm/sec
//#define ACCELERATIONS {800, 800, 30, 250} // mm/sec^2??
#define ACCELERATIONS {80, 80, 3, 25}
#define ACCELERATIONS {800, 800, 30, 250} // mm/sec^2??
//#define ACCELERATIONS {80, 80, 3, 25}
#define DRIVE_STEPS_PER_UNIT {91.4286, 91.4286, 4000, 929}
#define INSTANT_DVS {15.0, 15.0, 0.4, 15.0} // (mm/sec)
#define GCODE_LETTERS { 'X', 'Y', 'Z', 'E', 'F' } // The drives and feedrate in a GCode

123
README
View file

@ -1,28 +1,125 @@
This firmware is intended to be a fully object-oriented highly modular control p
rogram for RepRap self-replicating 3D printers.
RepRapFirmware - Main Program
This firmware is intended to be a fully object-oriented highly modular control program for
RepRap self-replicating 3D printers.
It owes a lot to Marlin and to the original RepRap FiveD_GCode.
General design principles:
* Control by RepRap G Codes. These are taken to be machine independent,
though some may be unsupported.
* Control by RepRap G Codes. These are taken to be machine independent, though some may be unsupported.
* Full use of C++ OO techniques,
* Make classes hide their data,
* Make everything as stateless as possible,
* No use of conditional compilation except for #include guards - if you
need that, you should be forking the repository to make a new
branch - let the repository take the strain,
* Concentration of all machine-dependent defintions and code in Platform.h
and Platform.cpp,
* No use of conditional compilation except for #include guards - if you need that, you should be
forking the repository to make a new branch - let the repository take the strain,
* Concentration of all machine-dependent defintions and code in Platform.h and Platform.cpp,
* No specials for (X,Y) or (Z) - all movement is 3-dimensional,
* Try to be efficient in memory use, but this is not critical,
* Labour hard to be efficient in time use, and this is critical,
* Don't abhor floats - they work fast enough if you're clever,
* Don't avoid arrays and structs/classes,
* Don't avoid pointers,
* Use operator and function overloading where appropriate, particulary for
vector algebra.
* Use operator and function overloading where appropriate, particularly for vector algebra.
Naming conventions:
* #defines are all capitals with optional underscores between words
* No underscores in other names - MakeReadableWithCapitalisation
* Class names and functions start with a CapitalLetter
* Variables start with a lowerCaseLetter
* Use veryLongDescriptiveNames
Structure:
There are six main classes:
* RepRap
* GCodes
* Heat
* Move
* Platform, and
* Webserver
RepRap:
This is just a container class for the single instances of all the others, and otherwise does very little.
GCodes:
This class is fed GCodes, either from the web interface or from GCode files, interprests them, and requests
actions from the RepRap machine via the other classes.
Heat:
This class imlements all heating and temperature control in the RepRap machine.
Move:
This class controls all movement of the RepRap machine, both along its axes, and in its extruder drives.
Platform:
This is the only class that knows anything about the physical setup of the RepRap machine and its
controlling electronics. It implements the interface between all the other classes and the RepRap machine.
All the other classes are completely machine-independent (though they may declare arrays dimensioned
to values #defined in Platform.h).
Webserver:
This class talks to the network (via Platform) and implements a simple webserver to give an interactive
interface to the RepRap machine. It uses the Knockout and Jquery Javascript libraries to achieve this.
When the software is running there is one single instance of each main class, and all the memory allocation is
done on initialisation. new/malloc should not be used in the general running code, and delete is never
used. Each class has an Init() function that resets it to its boot-up state; the constructors merely handle
that memory allocation on startup. Calling RepRap.Init() calls all the other Init()s in the right sequence.
There are other ancilliary classes that are declared in the .h files for the master classes that use them. For
example, Move has a DDA class that implements a Bresenham/digital differential analyser.
Timing:
There is a single interrupt chain entered via Platform.Interrupt(). This controls movement step timing, and
this chain of code should be the only place that volatile declarations and structure/variable-locking are
required. All the rest of the code is called sequentially and repeatedly as follows:
All the main classes have a Spin() function. These are called in a loop by the RepRap.Spin() function and implement
simple timesharing. No class does, or ever should, wait inside one of its functions for anything to happen or call
any sort of delay() function. The general rule is:
Can I do a thing?
Yes - do it
No - set a flag/timer to remind me to do it next-time-I'm-called/at-a-future-time and return.
The restriction this strategy places on almost all the code in the firmware (that it must execute quickly and
never cause waits or delays) is balanced by the fact that none of that code needs to worry about synchronicity,
locking, or other areas of code accessing items upon which it is working. As mentioned, only the interrupt
chain needs to concern itself with such problems. Unlike movement, heating (including PID controllers) does
not need the fast precision of timing that interrupts alone can offer. Indeed, most heating code only needs
to execute a couple of times a second.
Most data is transferred bytewise, with classes typically containg code like this:
Is a byte available for me?
Yes
read it and add it to my buffer
Is my buffer complete?
Yes
Act on the contents of my buffer
No
Return
No
Return
Note that it is simple to raise the "priority" of any class's activities relative to the others by calling its
Spin() function more than once from RepRap.Spin().
--------------------------------------------------------------------------------
@ -49,7 +146,7 @@ The password when the web browser asks for it is "reprap" with no quotes.
The password is intended to stop fidgety friends or colleagues from playing
with your RepRap. It is not intended to stop international cyberterrorists
working in a hollowed-out volcano from controlling your RepRap from the next
hiding in a hollowed-out volcano from controlling your RepRap from the next
continent. For example, it is transmitted unencrypted...
If you open the Arduino serial monitor (115200 baud) you should see a
@ -63,7 +160,7 @@ Actually acting upon them will be added shortly :-)
Version 0.2 pre-alpha
Started: 18 November 2012
This date: 1 March 2013
This date: 12 June 2013
Adrian Bowyer
RepRap Professional Ltd

123
README~
View file

@ -1,28 +1,125 @@
This firmware is intended to be a fully object-oriented highly modular control p
rogram for RepRap self-replicating 3D printers.
RepRapFirmware - Main Program
This firmware is intended to be a fully object-oriented highly modular control program for
RepRap self-replicating 3D printers.
It owes a lot to Marlin and to the original RepRap FiveD_GCode.
General design principles:
* Control by RepRap G Codes. These are taken to be machine independent,
though some may be unsupported.
* Control by RepRap G Codes. These are taken to be machine independent, though some may be unsupported.
* Full use of C++ OO techniques,
* Make classes hide their data,
* Make everything as stateless as possible,
* No use of conditional compilation except for #include guards - if you
need that, you should be forking the repository to make a new
branch - let the repository take the strain,
* Concentration of all machine-dependent defintions and code in Platform.h
and Platform.cpp,
* No use of conditional compilation except for #include guards - if you need that, you should be
forking the repository to make a new branch - let the repository take the strain,
* Concentration of all machine-dependent defintions and code in Platform.h and Platform.cpp,
* No specials for (X,Y) or (Z) - all movement is 3-dimensional,
* Try to be efficient in memory use, but this is not critical,
* Labour hard to be efficient in time use, and this is critical,
* Don't abhor floats - they work fast enough if you're clever,
* Don't avoid arrays and structs/classes,
* Don't avoid pointers,
* Use operator and function overloading where appropriate, particulary for
vector algebra.
* Use operator and function overloading where appropriate, particularly for vector algebra.
Naming conventions:
* #defines are all capitals with optional underscores between words
* No underscores in other names - MakeReadableWithCapitalisation
* Class names and functions start with a CapitalLetter
* Variables start with a lowerCaseLetter
* Use veryLongDescriptiveNames
Structure:
There are six main classes:
* RepRap
* GCodes
* Heat
* Move
* Platform, and
* Webserver
RepRap:
This is just a container class for the single instances of all the others, and otherwise does very little.
GCodes:
This class is fed GCodes, either from the web interface or from GCode files, interprests them, and requests
actions from the RepRap machine via the other classes.
Heat:
This class imlements all heating and temperature control in the RepRap machine.
Move:
This class controls all movement of the RepRap machine, both along its axes, and in its extruder drives.
Platform:
This is the only class that knows anything about the physical setup of the RepRap machine and its
controlling electronics. It implements the interface between all the other classes and the RepRap machine.
All the other classes are completely machine-independent (though they may declare arrays dimensioned
to values #defined in Platform.h).
Webserver:
This class talks to the network (via Platform) and implements a simple webserver to give an interactive
interface to the RepRap machine. It uses the Knockout and Jquery Javascript libraries to achieve this.
When the software is running there is one single instance of each main class, and all the memory allocation is
done on initialisation. new/malloc should not be used in the general running code, and delete is never
used. Each class has an Init() function that resets it to its boot-up state; the constructors merely handle
that memory allocation on startup. Calling RepRap.Init() calls all the other Init()s in the right sequence.
There are other ancilliary classes that are declared in the .h files for the master classes that use them. For
example, Move has a DDA class that implements a Bresenham/digital differential analyser.
Timing:
There is a single interrupt chain entered via Platform.Interrupt(). This controls movement step timing, and
this chain of code should be the only place that volatile declarations and structure/variable-locking are
required. All the rest of the code is called sequentially and repeatedly as follows:
All the main classes have a Spin() function. These are called in a loop by the RepRap.Spin() function and implement
simple timesharing. No class does, or ever should, wait inside one of its functions for anything to happen or call
any sort of delay() function. The general rule is:
Can I do a thing?
Yes - do it
No - set a flag/timer to remind me to do it next-time-I'm-called/at-a-future-time and return.
The restriction this strategy places on almost all the code in the firmware (that it must execute quickly and
never cause waits or delays) is balanced by the fact that none of that code needs to worry about synchronicity,
locking, or other areas of code accessing items upon which it is working. As mentioned, only the interrupt
chain needs to concern itself with such problems. Unlike movement, heating (including PID controllers) does
not need the fast precision of timing that interrupts alone can offer. Indeed, most heating code only needs
to execute a couple of times a second.
Most data is transferred bytewise, with classes typically containg code like this:
Is a byte available for me?
Yes
read it and add it to my buffer
Is my buffer complete?
Yes
Act on the contents of my buffer
No
Return
No
Return
Note that it is simple to raise the "priority" of any class's activities relative to the others by calling its
Spin() function more than once from RepRap.Spin().
--------------------------------------------------------------------------------
@ -31,7 +128,7 @@ the RepRapPro Ltd Arduino DUE to Sanguinololu Adaptor.
(See https://github.com/reprappro/ARMadaptor)
Test compiling is with Arduino 1.5.2.
Test compiling was with Arduino 1.5.2.
Upload it to your Due, put the ether shield on it, plug in a
network cable, and copy the files in the SD-image folder onto the SD.
@ -63,7 +160,7 @@ Actually acting upon them will be added shortly :-)
Version 0.2 pre-alpha
Started: 18 November 2012
This date: 1 March 2013
This date: 12 June 2013
Adrian Bowyer
RepRap Professional Ltd

29
RepRapFirmware.ino
View file

@ -77,7 +77,7 @@ interface to the RepRap machine. It uses the Knockout and Jquery Javascript lib
When the software is running there is one single instance of each class, and all the memory allocation is
When the software is running there is one single instance of each main class, and all the memory allocation is
done on initialisation. new/malloc should not be used in the general running code, and delete is never
used. Each class has an Init() function that resets it to its boot-up state; the constructors merely handle
that memory allocation on startup. Calling RepRap.Init() calls all the other Init()s in the right sequence.
@ -85,6 +85,13 @@ that memory allocation on startup. Calling RepRap.Init() calls all the other In
There are other ancilliary classes that are declared in the .h files for the master classes that use them. For
example, Move has a DDA class that implements a Bresenham/digital differential analyser.
Timing:
There is a single interrupt chain entered via Platform.Interrupt(). This controls movement step timing, and
this chain of code should be the only place that volatile declarations and structure/variable-locking are
required. All the rest of the code is called sequentially and repeatedly as follows:
All the main classes have a Spin() function. These are called in a loop by the RepRap.Spin() function and implement
simple timesharing. No class does, or ever should, wait inside one of its functions for anything to happen or call
any sort of delay() function. The general rule is:
@ -93,6 +100,26 @@ any sort of delay() function. The general rule is:
Yes - do it
No - set a flag/timer to remind me to do it next-time-I'm-called/at-a-future-time and return.
The restriction this strategy places on almost all the code in the firmware (that it must execute quickly and
never cause waits or delays) is balanced by the fact that none of that code needs to worry about synchronicity,
locking, or other areas of code accessing items upon which it is working. As mentioned, only the interrupt
chain needs to concern itself with such problems. Unlike movement, heating (including PID controllers) does
not need the fast precision of timing that interrupts alone can offer. Indeed, most heating code only needs
to execute a couple of times a second.
Most data is transferred bytewise, with classes typically containg code like this:
Is a byte available for me?
Yes
read it and add it to my buffer
Is my buffer complete?
Yes
Act on the contents of my buffer
No
Return
No
Return
Note that it is simple to raise the "priority" of any class's activities relative to the others by calling its
Spin() function more than once from RepRap.Spin().

22
SD-image/gcodes/ktst.g Normal file
View file

@ -0,0 +1,22 @@
G1 F1800.000 E-1.00000
G1 Z0.120 F3600.000
G1 X79.749 Y80.881
G1 F1800.000 E1.00000
G1 X79.979 Y80.671 F540.000 E0.00393
G1 X80.579 Y80.211 E0.00954
G1 X81.049 Y79.911 E0.00703
G1 X81.529 Y79.661 E0.00683
G1 X96.069 Y73.641 E0.19854
G1 X96.779 Y73.381 E0.00954
G1 X97.329 Y73.231 E0.00719
G1 X97.609 Y73.181 E0.00359
G1 X98.169 Y73.111 E0.00712
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