Code to drive a CNC machine via a PC LPT port lookalike 25 pin 'D', experiment in 'PC/Mach3' replacement. Designed to compile and run on mbed LPC1768, Freescale KL25Z and Freescale KL46Z. Proved on LPC1768 and KL25Z, problem with serial port on KL46Z. Reads subset of 'G Codes' through usb/serial port and drives 3 stepper/servo drives for X, Y and Z, also similar Step/Dir outputs for spindle motor control. Emulates PC LPT, outputs 'charge pump', proved driving Seig KX3 CNC mill

Dependencies:   MODSERIAL mbed

Revision:
0:5d0f270bfc87
Child:
1:66ee619f206b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/arith.cpp	Fri Jan 31 11:16:21 2014 +0000
@@ -0,0 +1,110 @@
+#include "mbed.h"
+#include "cnc.h"
+using namespace std;
+
+extern  Serial  pc;
+extern  double  feed_rate;
+const  long ball_screw_pitch_mm =   4.0,    //  KX3 has 4mm ball screws
+            motor_step_per_rev  =   200,    //  KX3 has 200 step per rev steppers
+            micro_steps         =   32,      //  Arc Eurotrade choice 2,4,5,8,10,16,20,25,32,40,50,64,100,125,128
+            pulses_per_mm       =   (micro_steps * motor_step_per_rev) / ball_screw_pitch_mm,
+
+            interrupt_period_us =   24, //16,
+            interrupt_freq_Hz   =   1000000 / interrupt_period_us,  //  Serious limit when doing all in software, no real limit with FPGA
+            max_pulse_freq_Hz   =   interrupt_freq_Hz / 6,  //  strictly 4, but allow a good margin
+            max_mm_per_min      =   (60 * max_pulse_freq_Hz) / pulses_per_mm;
+
+const   double  n_for_onemmpermin   = (double)(pulses_per_mm * interrupt_period_us) * pow(2.0,32) / 60000000.0, //  n pir to produce 1mm/min travel
+                feed_rate_max       = 300.0,
+                feed_rate_min       = 0.0,
+                spindle_max         = 5000.0,
+                spindle_min         = 0.0;
+//The output frequency F<sub>out</sub> = 'Kernel Speed (Hz)' * n / (2 to the power of 32)
+
+struct  Gparams    last_position;
+void    grain_clr   (struct singleGparam & g)  {
+    g.dbl = 0.0;
+    g.ul = 0L;
+    g.i = g.c = 0;
+    g.changed = false;
+}
+void    pirs_clr2    (struct Gparams & p)   {
+    grain_clr   (p.x);    grain_clr   (p.y);    grain_clr   (p.z);    grain_clr   (p.i);    grain_clr   (p.j);
+    grain_clr   (p.r);    grain_clr   (p.a);    grain_clr   (p.b);    grain_clr   (p.c);    grain_clr   (p.d);
+}
+void    init_last_position  ()  {
+    pirs_clr2    (last_position);
+}
+
+double  find_distance   (struct Gparams & from, struct Gparams & to, struct Gparams & distance)    {
+    distance.x.dbl    = to.x.dbl - from.x.dbl;
+    distance.y.dbl    = to.y.dbl - from.y.dbl;
+    distance.z.dbl    = to.z.dbl - from.z.dbl;   //  Yes, Pythagoras does work in 3D
+return  sqrt ((distance.x.dbl * distance.x.dbl) + (distance.y.dbl * distance.y.dbl) + (distance.z.dbl * distance.z.dbl));
+}
+
+double  find_traverse_time  (double dist, double rate)  {   //  dist mm, rate mm/min
+    return  60.0 * dist / rate;                             //  time secs
+}
+
+long    find_traverse_ticks (double dist, double rate)  {   //  dist mm, rate mm/min
+    return (long)(find_traverse_time(dist, rate) * 1000000.0) / interrupt_period_us;
+}
+
+/*void    craptest    ()  {
+    Gparams    to, distance;
+    double  dist;
+//    long    q = NCO_n_per_Hz;
+//    feed_rate   =   46.5;   //  global
+//    from.x.d    =   0.0;
+//    from.y.d    =   0.0;
+//    from.z.d    =   0.0;
+    to.x.d      =   45.0;
+    to.y.d      =   -12.375;
+    to.z.d      =   -3.142;
+    dist    = find_distance (last_position, to, distance);
+    pc.printf   ("From X %f Y %f Z %f to X %f Y %f Z %f\r\n",last_position.x.d, last_position.y.d, last_position.z.d, to.x.d, to.y.d, to.z.d);
+    pc.printf   ("Dist X %f Y %f Z %f, total %f\r\n", distance.x.d, distance.y.d, distance.z.d, dist);
+    pc.printf   ("To move %f mm at feed rate %f mm/min takes %f seconds\r\n", dist, feed_rate, find_traverse_time(dist, feed_rate));
+    pc.printf   ("This involves %d interrupt ticks\r\n", find_traverse_ticks(dist, feed_rate));
+//    pc.printf   ("NCO freq = %f when n = %d\r\n", NCO_freq_from_n(q), q);
+//    pc.printf   ("Nfor1mmpersec is %f, pulses_per_mm is %d\r\n",onemmpersec, pulses_per_mm);
+}*/
+
+void    copy_grain  (struct singleGparam & d, struct singleGparam & s)    {
+    d.dbl = s.dbl;
+    d.ul = s.ul;
+    d.i = s.i;
+    d.c = s.c;
+    d.changed = s.changed;
+}
+
+void    copy_pirs   (struct Gparams & d, struct Gparams & s)  {
+    copy_grain  (d.x, s.x);
+    copy_grain  (d.y, s.y);
+    copy_grain  (d.z, s.z);
+    copy_grain  (d.i, s.i);
+    copy_grain  (d.j, s.j);
+    copy_grain  (d.r, s.r);
+    copy_grain  (d.a, s.a);
+    copy_grain  (d.b, s.b);
+    copy_grain  (d.c, s.c);
+    copy_grain  (d.d, s.d);
+}
+
+/*void    swap_pirs   (struct pirs * d, struct pirs * s)  {
+//void    swap_pirs   ()  {
+    struct  pirs    pira, pirb;
+    struct  pirs *  ppa, * ppb, * pptmp;
+    ppa = & pira;
+    ppb = & pirb;
+    ppa->x.d = 1.0;
+    ppa->y.d = 2.0;
+    ppb->x.d = 2.0;
+    ppb->y.d = 1.0;
+    pc.printf   ("pira x = %f, y = %f, pirb x = %f, y = %f,\r\n", ppa->x.d, ppa->y.d, ppb->x.d, ppb->y.d);
+    pptmp = ppa;
+    ppa = ppb;
+    ppb = pptmp;
+    pc.printf   ("pira x = %f, y = %f, pirb x = %f, y = %f,\r\n", ppa->x.d, ppa->y.d, ppb->x.d, ppb->y.d);
+}*/