atusb: updated and improved CAM script

- atusb/cam2/mkmk: updated for new board
- atusb/cam2/mkmk: further increased board to board spacing, to reduce
  board deflection
- atusb/cam2/mkmk: decreased nominal mill diameter to 20 mil to compensate
  for board/tool deflection
- atusb/cam2/mkmk: added target "dplot" to visualize the sequence in which
  holes are drilled

atusb/cam2/mkmk

@@ -6,21 +6,23 @@ cameo <<EOF
 mm
 
 gerber 35mil ../atusb-PCB_Edges.gbr
-align 1 8.1mm 11.2mm	# align relative to board corner
-translate 25mm 2mm	# move to PCB zone assigned to project
-translate 2mm 21mm	# move a bit further
-array 19mm 36mm 3 0	# skip over previous boards
-z 0 -56.1mm		# board surface
+align 1 4.6mm 9.0mm	# align relative to board corner
+translate 3mm 3mm	# move to PCB zone assigned to project
+array 20mm 37mm 3 0	# skip over previous boards
+z 0 -58.9mm		# board surface (tool fully retracted)
+z 1.5mm			# slack for extending the tool
 z -0.8mm		# board thickness
 z -0.5mm		# tool extra depth
 clear
 
 excellon ../atusb.drl
 drill 7mil 15mil	# 12.5-13.5 mil drill
+optimize
 write drill.gp
 
 remainder
-mill 32mil 0.01mm	# 35 mil endmill; pretend it is a little smaller
+mill 20mil 0.01mm	# 35 mil endmill; pretend it is a little smaller,
+			# to compensate for tool/board deflections
 write mill.gp
 
 remainder
@@ -40,7 +42,7 @@ cat <<EOF >Makefile
 SPOOL=/home/moko/svn.openmoko.org/developers/werner/cncmap/spool/spool
 CNGT=/home/qi/cae-tools/cngt/cngt
 
-.PHONY:		mill drill cng plot
+.PHONY:		mill drill cng plot dplot
 
 mill:
 		PORT=/dev/ttyUSB0 \$(SPOOL) mill.rml
@@ -49,9 +51,13 @@ drill:
 		PORT=/dev/ttyUSB0 \$(SPOOL) drill.rml
 
 cng:
-		\$(CNGT) -56.1 20 mill.gp
+		\$(CNGT) -57.4 20 mill.gp
 
 plot:
 		echo 'plot "drill.gp" with points, "mill.gp" with lines' | \
 		  gnuplot -persist
+
+dplot:
+		echo 'plot "< sed /^\$\$/d drill.gp" with linespoints' | \
+		  gnuplot -persist
 EOF