Position reporting, refactored system variables, serial print fixes, updated streaming scripts.

- Added machine position reporting to status queries. This will be
further developed with part positioning/offsets and maintaining
location upon reset.

- System variables refactored into a global struct for better
readability.

- Removed old obsolete Ruby streaming scripts. These were no longer
compatible. Updated Python streaming scripts.

- Fixed printFloat() and other printing functions.

- Decreased planner buffer back to 18 blocks and increased TX serial
buffer to 64 bytes. Need the memory space for future developments.

- Begun adding run-time modes to grbl, where block delete toggle, mm/in
reporting modes, jog modes, etc can be set during runtime. Will be
fleshed out and placed into EEPROM when everything is added.

script/Obsolete/console

@@ -0,0 +1,5 @@
+socat -d -d READLINE /dev/tty.usbmodem26221,nonblock=1,clocal=1
+socat -d -d READLINE /dev/tty.usbmodem621,nonblock=1,clocal=1
+socat -d -d READLINE /dev/tty.usbserial-A700e0GO,clocal=1,nonblock=1,cread=1,cs8,ixon=1,ixoff=1
+socat -d -d READLINE /dev/tty.usbserial-A9007QcR,clocal=1,nonblock=1,cread=1,cs8,ixon=1,ixoff=1
+#socat -d -d READLINE /dev/tty.FireFly-A964-SPP-1,clocal=1,nonblock=1,cread=1,cs8,ixon=1,ixoff=1

script/Obsolete/proxy

@@ -0,0 +1,2 @@
+socat -d -d tcp4-listen:5001,fork /dev/tty.usbserial-A4001o6L,clocal=1,nonblock=1,cread=1,cs8,ixon=1,ixoff=1
+

script/Obsolete/stream

@@ -0,0 +1,2 @@
+#!/usr/bin/ruby
+require 'script/stream'

script/Obsolete/stream.rb

@@ -0,0 +1,50 @@
+require 'rubygems'
+require 'optparse'
+require 'serialport'
+
+
+options_parser = OptionParser.new do |opts|
+  opts.banner = "Usage: stream [options] gcode-file"
+  opts.on('-v', '--verbose', 'Output more information') do
+    $verbose = true
+  end   
+
+  opts.on('-p', '--prebuffer', 'Prebuffer commands') do
+    $prebuffer = true
+  end   
+  
+  opts.on('-h', '--help', 'Display this screen') do
+    puts opts
+    exit
+  end
+end
+options_parser.parse!
+if ARGV.empty?
+  puts options_parser
+  exit
+end
+
+# SerialPort.open('/dev/tty.FireFly-A964-SPP-1', 115200) do |sp|
+SerialPort.open('/dev/tty.usbserial-A700e0GO', 9600) do |sp|
+  sp.write("\r\n\r\n");
+  sleep 1
+  ARGV.each do |file|
+    puts "Processing file #{file}"
+    prebuffer = $prebuffer ? 20 : 0
+    File.readlines(file).each do |line|
+      next if line.strip == ''
+      puts line.strip
+      sp.write("#{line.strip}\r\n");
+      if prebuffer == 0
+        begin
+          result = sp.gets.strip
+          puts "Grbl >> #{result}" #unless result == 'ok'
+        end while !(result =~ /^ok|^error/)
+      else
+        prebuffer -= 1
+      end
+    end
+  end
+  puts "Done."
+  sleep 500
+end

script/Obsolete/trapezoid_simulator.rb

@@ -0,0 +1,78 @@
+require 'pp'
+
+def estimate_acceleration_distance(initial_rate, target_rate, acceleration) 
+    (target_rate*target_rate-initial_rate*initial_rate)/(2*acceleration)
+end
+
+def intersection_distance(initial_rate, final_rate, acceleration, distance) 
+    (2*acceleration*distance-initial_rate*initial_rate+final_rate*final_rate)/(4*acceleration)
+end
+
+ACCELERATION_TICKS_PER_SECOND = 20
+
+def trapezoid_params(step_event_count, nominal_rate, rate_delta, entry_factor, exit_factor)
+  initial_rate = (nominal_rate * entry_factor).round
+  final_rate = (nominal_rate * exit_factor).round
+  acceleration_per_minute = rate_delta*ACCELERATION_TICKS_PER_SECOND*60
+
+  accelerate_steps = 
+    estimate_acceleration_distance(initial_rate, nominal_rate, acceleration_per_minute).round;
+  decelerate_steps = 
+    estimate_acceleration_distance(nominal_rate, final_rate, -acceleration_per_minute).round;
+  
+  # Calculate the size of Plateau of Nominal Rate. 
+  plateau_steps = step_event_count-accelerate_steps-decelerate_steps;
+  
+  # Is the Plateau of Nominal Rate smaller than nothing? That means no cruising, and we will
+  # have to use intersection_distance() to calculate when to abort acceleration and start braking 
+  # in order to reach the final_rate exactly at the end of this block.
+  if (plateau_steps < 0)
+    accelerate_steps = 
+      intersection_distance(initial_rate, final_rate, acceleration_per_minute, step_event_count).round
+    plateau_steps = 0;
+  end
+  
+  accelerate_until = accelerate_steps;
+  decelerate_after = accelerate_steps+plateau_steps;
+  {:step_event_count => step_event_count,
+   :initial_rate => initial_rate,
+   :final_rate => final_rate,
+   :nominal_rate => nominal_rate,
+   :rate_delta => rate_delta,
+   :accelerate_until => accelerate_until,
+   :decelerate_after => decelerate_after}
+end
+
+def simulate_trapezoid(params)
+  result = {}
+  rate = params[:initial_rate]
+  step_event = 0.0
+  max_rate = 0
+  while(step_event < params[:step_event_count]) do
+    step_events_in_frame = rate/60.0/ACCELERATION_TICKS_PER_SECOND
+    step_event += step_events_in_frame
+    max_rate = rate if rate > max_rate
+    if (step_event < params[:accelerate_until]) 
+      rate += params[:rate_delta]
+    elsif (step_event > params[:decelerate_after])
+      if rate > params[:final_rate]
+        rate -= params[:rate_delta]
+      else
+        return :underflow_at => step_event, :final_rate => rate, :max_rate => max_rate
+      end
+    end
+#    puts "#{step_event} #{rate}"
+  end 
+  {:final_rate => rate, :max_rate => max_rate}
+end
+
+(10..100).each do |rate|
+  (1..5).each do |steps|
+    params = trapezoid_params(steps*1000, rate*100, 10, 0.1, 0.1)
+    result = simulate_trapezoid(params)
+  #  puts params.inspect
+    line = "#{steps*10} final: #{result[:final_rate]} == #{params[:final_rate]} peak: #{result[:max_rate]} == #{params[:nominal_rate]} d#{params[:nominal_rate]-result[:max_rate]} "
+    line << " (underflow at #{result[:underflow_at]})" if result[:underflow_at]
+    puts line
+  end
+end