diff --git a/.gitignore b/.gitignore
index 07f028b..8330e7b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -110,3 +110,7 @@ venv.bak/
 # pycharm
 .idea/
 .idea/*
+
+*yacctab.py
+*lextab.py
+
diff --git a/src/pymodaq_plugins_teaching/hardware/spectrometer.py b/src/pymodaq_plugins_teaching/hardware/spectrometer.py
index ed1c8a7..370caa7 100644
--- a/src/pymodaq_plugins_teaching/hardware/spectrometer.py
+++ b/src/pymodaq_plugins_teaching/hardware/spectrometer.py
@@ -4,21 +4,34 @@
 class Spectrometer:
 
     axis = ['lambda0']
+    gratings = ['G300', 'G1200']
+
     Nactuators = len(axis)
     Nx = 256
+    infos = 'Spectrometer Controller Wrapper 0.0.1'
 
-    def __init__(self, positions=[632.], noise=0.1, amp=10, wh=20):
+    def __init__(self, positions=[632.], noise=0.1, amp=10, wh=20, grating=gratings[0]):
         super().__init__()
         if positions is None:
             self.current_positions = dict(zip(self.axis, [0. for ind in range(self.Nactuators)]))
         else:
             assert isinstance(positions, list)
             assert len(positions) == self.Nactuators
-            self.current_positions = positions
+            self.current_positions = dict(zip(self.axis, positions))
 
         self._amp = amp
         self._noise = noise
         self._wh = wh
+        self._grating = grating
+
+    @property
+    def grating(self):
+        return self._grating
+
+    @grating.setter
+    def grating(self, grat):
+        if grat in self.gratings:
+            self._grating = grat
 
     @property
     def amplitude(self):
@@ -47,25 +60,31 @@ def width(self, value):
         if value > 0.:
             self._wh = value
 
+    def set_wavelength(self, value, set_type='abs'):
+        if value < 0:
+            raise ValueError('Wavelength cannot be negative')
 
-    def check_position(self, axis):
-        return self.current_positions[axis]
-
-    def move_abs(self, position, axis):
-        self.current_positions[axis] = position
+        if set_type == 'abs':
+            self.current_positions['lambda0'] = value
+        else:
+            self.current_positions['lambda0'] += value
 
-    def move_rel(self, position, axis):
-        self.current_positions[axis] += position
+    def get_wavelength(self):
+        return self.current_positions['lambda0']
 
     def get_xaxis(self):
-        return (np.linspace(0, self.Nx, self.Nx, endpoint=False) - self.Nx / 2) * 0.25 +\
+        if self._grating == 'G300':
+            coeff = 0.7
+        elif self._grating == 'G1200':
+            coeff = 0.25
+        return (np.linspace(0, self.Nx, self.Nx, endpoint=False) - self.Nx / 2) * coeff +\
                self.current_positions['lambda0']
 
     def set_Mock_data(self):
         """
         """
         x_axis = self.get_xaxis()
-        return self._amp * gauss1D(x_axis, self.current_positions['H'], self._wh) +\
+        return self._amp * gauss1D(x_axis, self.current_positions['lambda0'], self._wh) +\
                self._noise * np.random.rand(self.Nx)
 
     def get_data_output(self, data=None):