Diff: main.cpp

Revision:

0:5c352dab4496

Child:

1:93d357b92fd0

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Jan 27 19:51:07 2011 +0000
@@ -0,0 +1,167 @@
+/*
+ * main.cpp
+ *
+ * Copyright (c) 2011 Peter Brier
+ *
+ *   This file is part of the LaOS project (see: http://wiki.protospace.nl/index.php/LaOS)
+ *
+ *   LaOS is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   LaOS is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with LaOS.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * This program implements Bresenham line algorithm program (2D)
+ * see: http://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm
+ * In addition: we controll a Z-axis and a laser.
+ * Note: Fixed speed lasering (no accelleration). Actually: vector speed depends on angle. Perpendicular to X or Y axis is lowest speed
+ * At 45 degrees is is sqrt(2) faster (approx 40%). Simple program, no line buffering. Considerable jitter on pulses.
+ *
+ */
+#include "mbed.h"
+
+// serial comm
+Serial pc(USBTX, USBRX); 
+
+// status leds
+DigitalOut led1(LED1);
+DigitalOut led2(LED2);
+DigitalOut led3(LED3);
+DigitalOut led4(LED4);
+
+// motors
+DigitalOut xdir(p26);
+DigitalOut xstep(p25);
+DigitalOut ydir(p24);
+DigitalOut ystep(p23);
+DigitalOut zdir(p22);
+DigitalOut zstep(p21);
+
+// laser
+DigitalOut laser(p27);
+
+// globals
+Ticker ticker;  // Timer
+
+// Besenham variables
+int state, laseron;
+int x0,y0,x1,y1,z0,z1;  // positions: 0=current, 1=new
+int dx, sx; // step
+int dy, sy;  // delta
+int err, e2; // error
+
+
+/**
+*** ticker: implement timer ticker, step if required
+**/
+void tick() 
+{
+  // Control X,Y: line tracker
+  switch ( state )
+  {
+    case 0: // idle (make sure laser is off)
+      laser = laseron =  0;
+      break;
+    case 1: // init
+      dx = abs(x1-x0);
+      sx = x0<x1 ? 1 : -1;
+      dy = abs(y1-y0);
+      sy = y0<y1 ? 1 : -1; 
+      err = (dx>dy ? dx : -dy)/2;
+      xdir = sx > 0;
+      ydir = sy > 0;
+      state++;
+      laser = laseron;
+      break;
+    case 2: // moving
+      if (x0==x1 && y0==y1) 
+        state = 0;
+      else
+      {
+        e2 = err;
+        if (e2 >-dx) { err -= dy; x0 += sx; xstep = 1;}
+        if (e2 < dy) { err += dx; y0 += sy; ystep = 1;}
+      }
+      break;
+  }
+  
+  // Controll Z: tracking controller (independent of XY motion, not queued)
+  if ( z1 != z0 ) 
+  {
+    zdir = z1 > z0;
+    wait_us(5);
+    zstep= 1;
+    if ( z1 > z0 ) z0++;
+    else z0--;
+  }
+  
+  if ( xstep == 1 || ystep == 1 || zstep == 1 )
+  {
+    wait_us(5);
+    xstep = ystep = zstep = 0;
+  }
+  
+  // diagnostic info
+  led1 = xdir;
+  led2 = ydir;
+  led3 = zdir;
+  led4 = laser;
+} // ticker
+
+
+
+/**
+*** main()
+*** Read commands, report state
+**/
+int main() 
+{
+  int v=100,c=0,z=0;
+
+  pc.baud(115200);  
+  ticker.attach_us(&tick, v); // the address of the function to be attached (flip) and the interval (microseconds)
+
+  // init
+  state = laser = xstep = xdir = ystep = ydir = zstep = zdir = 0;
+  
+  while( 1 )
+  {    
+     scanf("%d", &c); 
+     switch( c )
+     {
+          case 0: // move x,y (laser off)
+            scanf("%d %d", &x1, &y1);
+            laseron = 0;
+            state = 1; 
+            break;
+          case 1: // line x,y (laser on)
+            scanf("%d %d", &x1, &y1);
+            laseron = 1;
+            state = 1; 
+            break;
+          case 2: // move z 
+            scanf("%d", &z1); 
+            break;
+          case 3: // set t (1/v)
+            scanf("%d", &v);
+            ticker.attach_us(&tick, v);
+            break;
+         case 4: // set x,y,z absolute
+            scanf("%d %d %d", &x0, &y0, &z);
+            z1 = z0 = z;
+         case 5: // nop
+           break;
+         default: // I do not understand: stop motion
+            state = 0;
+          break;
+    }
+    printf("%d %d %d %d %d %d\r\n", state, x0, y0, z0, v, laseron);
+  }
+}