diff --git a/cnc/gmachine.py b/cnc/gmachine.py
index 0cab36b..9a6d95c 100644
--- a/cnc/gmachine.py
+++ b/cnc/gmachine.py
@@ -313,7 +313,8 @@ class GMachine(object):
             c = 'G1'
         # read parameters
         if self._absoluteCoordinates:
-            coord = gcode.coordinates(self._position, self._convertCoordinates)
+            coord = gcode.coordinates(self._position - self._local,
+                                      self._convertCoordinates)
             coord = coord + self._local
             delta = coord - self._position
         else:
@@ -336,19 +337,19 @@ class GMachine(object):
             if l > 0:
                 proportion = abs(delta) / l
                 if proportion.x > 0:
-                    v = MAX_VELOCITY_MM_PER_MIN_X / proportion.x
+                    v = int(MAX_VELOCITY_MM_PER_MIN_X / proportion.x)
                     if v < vl:
                         vl = v
                 if proportion.y > 0:
-                    v = MAX_VELOCITY_MM_PER_MIN_Y / proportion.y
+                    v = int(MAX_VELOCITY_MM_PER_MIN_Y / proportion.y)
                     if v < vl:
                         vl = v
                 if proportion.z > 0:
-                    v = MAX_VELOCITY_MM_PER_MIN_Z / proportion.z
+                    v = int(MAX_VELOCITY_MM_PER_MIN_Z / proportion.z)
                     if v < vl:
                         vl = v
                 if proportion.e > 0:
-                    v = MAX_VELOCITY_MM_PER_MIN_E / proportion.e
+                    v = int(MAX_VELOCITY_MM_PER_MIN_E / proportion.e)
                     if v < vl:
                         vl = v
             self._move_linear(delta, vl)
@@ -391,9 +392,15 @@ class GMachine(object):
         elif c == 'G91':  # switch to relative coords
             self._absoluteCoordinates = False
         elif c == 'G92':  # switch to local coords
-            self._local = self._position - \
-                          gcode.coordinates(Coordinates(0.0, 0.0, 0.0, 0.0),
-                                            self._convertCoordinates)
+            if gcode.has_coordinates():
+                self._local = self._position - gcode.coordinates(
+                    Coordinates(self._position.x - self._local.x,
+                                self._position.y - self._local.y,
+                                self._position.z - self._local.z,
+                                self._position.e - self._local.e),
+                    self._convertCoordinates)
+            else:
+                self._local = self._position
         elif c == 'M3':  # spindle on
             spindle_rpm = gcode.get('S', self._spindle_rpm)
             if spindle_rpm < 0 or spindle_rpm > SPINDLE_MAX_RPM:
diff --git a/cnc/hal_virtual.py b/cnc/hal_virtual.py
index 56686c8..55e2982 100644
--- a/cnc/hal_virtual.py
+++ b/cnc/hal_virtual.py
@@ -165,10 +165,14 @@ def move(generator):
         assert f.count(f[0]) == len(f), "fast forwarded pulse detected"
     pt = time.time()
     assert direction_found, "direction not found"
-    assert ix / STEPPER_PULSES_PER_MM_X == delta.x, "x wrong number of pulses"
-    assert iy / STEPPER_PULSES_PER_MM_Y == delta.y, "y wrong number of pulses"
-    assert iz / STEPPER_PULSES_PER_MM_Z == delta.z, "z wrong number of pulses"
-    assert ie / STEPPER_PULSES_PER_MM_E == delta.e, "e wrong number of pulses"
+    assert round(ix / STEPPER_PULSES_PER_MM_X, 10) == delta.x,\
+        "x wrong number of pulses"
+    assert round(iy / STEPPER_PULSES_PER_MM_Y, 10) == delta.y,\
+        "y wrong number of pulses"
+    assert round(iz / STEPPER_PULSES_PER_MM_Z, 10) == delta.z, \
+        "z wrong number of pulses"
+    assert round(ie / STEPPER_PULSES_PER_MM_E, 10) == delta.e, \
+        "e wrong number of pulses"
     assert max(mx, my, mz, me) <= generator.total_time_s(), \
         "interpolation time or pulses wrong"
     logging.debug("Moved {}, {}, {}, {} iterations".format(ix, iy, iz, ie))
diff --git a/tests/test_gmachine.py b/tests/test_gmachine.py
index e640656..52d7beb 100644
--- a/tests/test_gmachine.py
+++ b/tests/test_gmachine.py
@@ -56,6 +56,8 @@ class TestGMachine(unittest.TestCase):
     # Test gcode commands.
     def test_g0_g1(self):
         m = GMachine()
+        m.do_command(GCode.parse_line("G0X10Y10Z11"))
+        self.assertEqual(m.position(), Coordinates(10, 10, 11, 0))
         m.do_command(GCode.parse_line("G0X3Y2Z1E-2"))
         self.assertEqual(m.position(), Coordinates(3, 2, 1, -2))
         m.do_command(GCode.parse_line("G1X1Y2Z3E4"))
@@ -185,7 +187,7 @@ class TestGMachine(unittest.TestCase):
         m.do_command(GCode.parse_line("X1Y1Z1E1"))
         self.assertEqual(m.position(), Coordinates(1, 1, 1, 1))
 
-    def test_g90_g92(self):
+    def test_g53_g92(self):
         m = GMachine()
         m.do_command(GCode.parse_line("G92X100Y100Z100E100"))
         m.do_command(GCode.parse_line("X101Y102Z103E104"))
@@ -196,9 +198,17 @@ class TestGMachine(unittest.TestCase):
         m.do_command(GCode.parse_line("G92X3Y4Z5E6"))
         m.do_command(GCode.parse_line("X0Y0Z0E0"))
         self.assertEqual(m.position(), Coordinates(0, 0, 0, 0))
-        m.do_command(GCode.parse_line("G90"))
+        m.do_command(GCode.parse_line("X1Y2Z3E4"))
+        self.assertEqual(m.position(), Coordinates(1, 2, 3, 4))
+        m.do_command(GCode.parse_line("G53"))
         m.do_command(GCode.parse_line("X6Y7Z8E9"))
         self.assertEqual(m.position(), Coordinates(6, 7, 8, 9))
+        m.do_command(GCode.parse_line("G92E0"))
+        m.do_command(GCode.parse_line("X6Y7Z8E1"))
+        self.assertEqual(m.position(), Coordinates(6, 7, 8, 10))
+        m.do_command(GCode.parse_line("G92"))
+        m.do_command(GCode.parse_line("X1Y1Z1E1"))
+        self.assertEqual(m.position(), Coordinates(7, 8, 9, 11))
 
     def test_g53_g91_g92(self):
         m = GMachine()