Add a draft of a script running testcases in SimulAVR.

This script also asks SimulAVR to generate pin traces of the X
and Y axis and even processes this data into a data file with
time, position and current speed of each axis.

Missing:

- Acceleration calculation.

- LOTS of polish.

testcases/.gitignore

@@ -0,0 +1,4 @@
+*.vcd
+*.data
+*.png
+

testcases/run-in-simulavr.sh

@@ -0,0 +1,107 @@
+#!/bin/bash
+
+# This should point to a SIMINFO-enabled SimulAVR executable:
+SIMULAVR="../../simulavr/src/simulavr"
+if [ ! -x "${SIMULAVR}" ]; then
+  echo "SimulAVR executable not found, please adjust"
+  echo "variables at the top of ${0}."
+  exit 1;
+fi
+
+
+# Prepare a pin tracing file, assuming a Gen7-v1.4 configuration. See
+# http://reprap.org/wiki/SimulAVR#Putting_things_together:_an_example
+echo "# X Dir"              > /tmp/tracein.txt
+echo "+ PORTA.A3-Out"      >> /tmp/tracein.txt
+echo "# X Step"            >> /tmp/tracein.txt
+echo "+ PORTA.A2-Out"      >> /tmp/tracein.txt
+echo "# Y Dir"             >> /tmp/tracein.txt
+echo "+ PORTA.A5-Out"      >> /tmp/tracein.txt
+echo "# Y Step"            >> /tmp/tracein.txt
+echo "+ PORTA.A4-Out"      >> /tmp/tracein.txt
+
+
+for GCODE_FILE in "triangle.gcode" "straight-speeds.gcode"; do
+
+  FILE="${GCODE_FILE%.gcode}"
+  VCD_FILE="${FILE}.vcd"
+  
+
+  # We assume here queue and rx buffer are large enough to read
+  # the file in one chunk. If not, raise MOVEBUFFER_SIZE in config.h.
+  "${SIMULAVR}" -c vcd:/tmp/tracein.txt:"${VCD_FILE}" \
+                -f ../build/teacup.elf \
+                -m 60000000000  < "${GCODE_FILE}"
+
+
+  # Make plottable files from VCD files.
+  # This is very rudimentary and does a lot of assumptions.
+  # For examble, pin data is assumed to always be b0/b1, pin naming
+  # is assumed to match the order in tracein.txt and starting at "0".
+  awk '
+    BEGIN {
+      dataFile = "'"${FILE}"'.data";
+      print "0 0 0 0 0" > dataFile;
+      xDir = yDir = 0;
+      xPos = yPos = 0;
+      xVel = yVel = 0;
+      yAcc = yAcc = 0;
+      lastxTime = lastyTime = 0;
+    }
+    /^#/ {
+      time = substr($0, 2);
+      next;
+    }
+    {
+      bit = substr($1, 2);
+      if ($2 == "0") { # X Dir
+        if (bit == 0) xDir = -1;
+        else if (bit == 1) xDir = 1;
+        else xDir = 0;
+      }
+      if ($2 == "2") { # Y Dir
+        if (bit == 0) yDir = -1;
+        else if (bit == 1) yDir = 1;
+        else yDir = 0;
+      }
+      if ($2 == "1") { # X Step, count only raising flanges
+        if (bit == 1) {
+          xPos += xDir;
+          xVel = 1000000000 / (time - lastxTime);
+          print time " " xPos " " yPos " " xVel " " yVel >> dataFile;
+          lastxTime = time;
+        }
+      }
+      if ($2 == "3") { # Y Step, count only raising flanges
+        if (bit == 1) {
+          yPos += yDir;
+          yVel = 1000000000 / (time - lastyTime);
+          print time " " xPos " " yPos " " xVel " " yVel >> dataFile;
+          lastyTime = time;
+        }
+      }
+    }
+  ' < "${VCD_FILE}"
+
+
+  # Finally, create a plot.
+  gnuplot << EOF
+    set terminal png size 1024,768
+    set output "${FILE}.png"
+
+    set title "${GCODE_FILE}"
+
+    set xlabel "X steps"
+    set ylabel "Y steps"
+    set y2label "feedrate [steps/s]"
+
+    #set origin 10,10;
+    plot "${FILE}.data" using (\$2):(\$3) with dots title "position", \
+         "${FILE}.data" using (\$2):(\$4) with dots title "X feedrate", \
+         "${FILE}.data" using (\$2):(\$5) with dots title "Y feedrate"
+EOF
+
+  display "${FILE}.png" &
+
+done
+