The code we are using at the moment is as displayed of the left.
#include "config.h"
char buffer[MAX_BUF]; // where we store the message until we get a ';'
int sofar; // how much is in the buffer
float px, py; // location
// speeds
float fr=0; // human version
long step_delay; // machine version
// settings
char mode_abs=1; // absolute mode?
/**
* delay for the appropriate number of microseconds
* @input ms how many milliseconds to wait
*/
void pause(long ms) {
delay(ms/1000);
delayMicroseconds(ms%1000); // delayMicroseconds doesn't work for values > ~16k.
}
/**
* Set the feedrate (speed motors will move)
* @input nfr the new speed in steps/second
*/
void feedrate(float nfr) {
if(fr==nfr) return; // same as last time? quit now.
if(nfr>MAX_FEEDRATE || nfr<MIN_FEEDRATE) { // don't allow crazy feed rates
Serial.print(F("New feedrate must be greater than "));
Serial.print(MIN_FEEDRATE);
Serial.print(F("steps/s and less than "));
Serial.print(MAX_FEEDRATE);
Serial.println(F("steps/s."));
return;
}
step_delay = 1000000.0/nfr;
fr=nfr;
}
/**
* Set the logical position
* @input npx new position x
* @input npy new position y
*/
void position(float npx,float npy) {
// here is a good place to add sanity tests
px=npx;
py=npy;
}
/**
* Uses bresenham's line algorithm to move both motors
* @input newx the destination x position
* @input newy the destination y position
**/
void line(float newx,float newy) {
long dx=newx-px;
long dy=newy-py;
int dirx=dx>0?1:-1;
int diry=dy>0?-1:1; // because the motors are mounted in opposite directions
dx=abs(dx);
dy=abs(dy);
long i;
long over=0;
if(dx>dy) {
for(i=0;i<dx;++i) {
m1step(dirx);
over+=dy;
if(over>=dx) {
over-=dx;
m2step(diry);
}
pause(step_delay);
}
} else {
for(i=0;i<dy;++i) {
m2step(diry);
over+=dx;
if(over>=dy) {
over-=dy;
m1step(dirx);
}
pause(step_delay);
}
}
px=newx;
py=newy;
}
// returns angle of dy/dx as a value from 0...2PI
static float atan3(float dy,float dx) {
float a=atan2(dy,dx);
if(a<0) a=(PI*2.0)+a;
return a;
}
// This method assumes the limits have already been checked.
// This method assumes the start and end radius match.
// This method assumes arcs are not >180 degrees (PI radians)
// cx/cy - center of circle
// x/y - end position
// dir - ARC_CW or ARC_CCW to control direction of arc
static void arc(float cx,float cy,float x,float y,float dir) {
// get radius
float dx = px - cx;
float dy = py - cy;
float radius=sqrt(dx*dx+dy*dy);
// find angle of arc (sweep)
float angle1=atan3(dy,dx);
float angle2=atan3(y-cy,x-cx);
float theta=angle2-angle1;
if(dir>0 && theta<0) angle2+=2*PI;
else if(dir<0 && theta>0) angle1+=2*PI;
theta=angle2-angle1;
// get length of arc
// float circ=PI*2.0*radius;
// float len=theta*circ/(PI*2.0);
// simplifies to
float len = abs(theta) * radius;
int i, segments = ceil( len * MM_PER_SEGMENT );
float nx, ny, angle3, scale;
for(i=0;i<segments;++i) {
// interpolate around the arc
scale = ((float)i)/((float)segments);
angle3 = ( theta * scale ) + angle1;
nx = cx + cos(angle3) * radius;
ny = cy + sin(angle3) * radius;
// send it to the planner
line(nx,ny);
}
line(x,y);
}
/**
* Look for character /code/ in the buffer and read the float that immediately follows it.
* @return the value found. If nothing is found, /val/ is returned.
* @input code the character to look for.
* @input val the return value if /code/ is not found.
**/
float parsenumber(char code,float val) {
char *ptr=buffer;
while(ptr && *ptr && ptr<buffer+sofar) {
if(*ptr==code) {
return atof(ptr+1);
}
ptr=strchr(ptr,' ')+1;
}
return val;
}
/**
* write a string followed by a float to the serial line. Convenient for debugging.
* @input code the string.
* @input val the float.
*/
void output(char *code,float val) {
Serial.print(code);
Serial.println(val);
}
/**
* print the current position, feedrate, and absolute mode.
*/
void where() {
output("X",px);
output("Y",py);
output("F",fr);
Serial.println(mode_abs?"ABS":"REL");
}
/**
* display helpful information
*/
void help() {
Serial.print(F("GcodeCNCDemo2AxisV1 "));
Serial.println(VERSION);
Serial.println(F("Commands:"));
Serial.println(F("G00 [X(steps)] [Y(steps)] [F(feedrate)]; - line"));
Serial.println(F("G01 [X(steps)] [Y(steps)] [F(feedrate)]; - line"));
Serial.println(F("G02 [X(steps)] [Y(steps)] [I(steps)] [J(steps)] [F(feedrate)]; - clockwise arc"));
Serial.println(F("G03 [X(steps)] [Y(steps)] [I(steps)] [J(steps)] [F(feedrate)]; - counter-clockwise arc"));
Serial.println(F("G04 P[seconds]; - delay"));
Serial.println(F("G90; - absolute mode"));
Serial.println(F("G91; - relative mode"));
Serial.println(F("G92 [X(steps)] [Y(steps)]; - change logical position"));
Serial.println(F("M18; - disable motors"));
Serial.println(F("M100; - this help message"));
Serial.println(F("M114; - report position and feedrate"));
Serial.println(F("All commands must end with a newline."));
}
/**
* Read the input buffer and find any recognized commands. One G or M command per line.
*/
void processCommand() {
int cmd = parsenumber('G',-1);
switch(cmd) {
case 0:
case 1: { // line
feedrate(parsenumber('F',fr));
line( parsenumber('X',(mode_abs?px:0)) + (mode_abs?0:px),
parsenumber('Y',(mode_abs?py:0)) + (mode_abs?0:py) );
break;
}
case 2:
case 3: { // arc
feedrate(parsenumber('F',fr));
arc(parsenumber('I',(mode_abs?px:0)) + (mode_abs?0:px),
parsenumber('J',(mode_abs?py:0)) + (mode_abs?0:py),
parsenumber('X',(mode_abs?px:0)) + (mode_abs?0:px),
parsenumber('Y',(mode_abs?py:0)) + (mode_abs?0:py),
(cmd==2) ? -1 : 1);
break;
}
case 4: pause(parsenumber('P',0)*1000); break; // dwell
case 90: mode_abs=1; break; // absolute mode
case 91: mode_abs=0; break; // relative mode
case 92: // set logical position
position( parsenumber('X',0),
parsenumber('Y',0) );
break;
default: break;
}
cmd = parsenumber('M',-1);
switch(cmd) {
case 18: // disable motors
disable();
break;
case 100: help(); break;
case 114: where(); break;
default: break;
}
}
/**
* prepares the input buffer to receive a new message and tells the serial connected device it is ready for more.
*/
void ready() {
sofar=0; // clear input buffer
Serial.print(F(">")); // signal ready to receive input
}
/**
* First thing this machine does on startup. Runs only once.
*/
void setup() {
Serial.begin(BAUD); // open coms
setup_controller();
position(0,0); // set staring position
feedrate((MAX_FEEDRATE + MIN_FEEDRATE)/2); // set default speed
help(); // say hello
ready();
}
/**
* After setup() this machine will repeat loop() forever.
*/
void loop() {
// listen for serial commands
while(Serial.available() > 0) { // if something is available
char c=Serial.read(); // get it
Serial.print(c); // repeat it back so I know you got the message
if(sofar<MAX_BUF-1) buffer[sofar++]=c; // store it
if(c=='\n') {
// entire message received
// we got a message and it ends with a semicolon
buffer[sofar]=0; // end the buffer so string functions work right
Serial.print(F("\r\n")); // echo a return character for humans
processCommand(); // do something with the command
ready();
}
}
#if CONTROLLER == AMS1
#include <AFMotorDrawbot.h>
// Initialize Adafruit stepper controller
AF_Stepper m1((int)STEPS_PER_TURN, 1);
AF_Stepper m2((int)STEPS_PER_TURN, 2);
void m1step(int dir) {
m1.onestep(dir);
}
void m2step(int dir) {
m2.onestep(dir);
}
void disable() {
m1.release();
m2.release();
}
void setup_controller() {}
#endif // CONTROLLER == AMS1
#include "config.h"
#if CONTROLLER == AMS2
//------------------------------------------------------------------------------
// INCLUDES
//------------------------------------------------------------------------------
#include <Wire.h>
#include <Adafruit_MotorShield.h>
#include "utility/Adafruit_PWMServoDriver.h"
#define AMS2_ADDRESS (0x61)
//------------------------------------------------------------------------------
// GLOBALS
//------------------------------------------------------------------------------
// Create the motor shield object with the default I2C address
Adafruit_MotorShield AFMS = Adafruit_MotorShield(AMS2_ADDRESS);
Adafruit_StepperMotor *m1 = AFMS.getStepper(STEPS_PER_TURN, 1); // to motor port #1 (M1 and M2)
Adafruit_StepperMotor *m2 = AFMS.getStepper(STEPS_PER_TURN, 2); // to motor port #2 (M3 and M4)
//------------------------------------------------------------------------------
// METHODS
//------------------------------------------------------------------------------
void m1step(int dir) {
m1->onestep(dir>0?FORWARD:BACKWARD,SINGLE);
}
void m2step(int dir) {
m2->onestep(dir>0?FORWARD:BACKWARD,SINGLE);
}
void disable() {
m1->release();
m2->release();
}
void setup_controller() {
AFMS.begin(); // create with the default frequency 1.6KHz
}
#endif // CONTROLLER == AMS2