fixes for uniax device

secop_psi/dpm.py

@@ -16,11 +16,13 @@
 # 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 #
 # Module authors:
-#   ...
+#   M. Zolliker <markus.zolliker@psi.ch>
 #
 # *****************************************************************************
+"""transducer DPM3 read out"""
 
-from secop.core import Readable, Parameter, FloatRange, BoolType, StringIO, HasIodev, IntRange, Done
+from secop.core import Drivable, Parameter, FloatRange, BoolType, StringIO,\
+     HasIodev, IntRange, Done, Attached, Command
 
 
 class DPM3IO(StringIO):
@@ -43,7 +45,7 @@ def float2hex(value, digits):
     return '%06X' % intvalue
 
 
-class DPM3(HasIodev, Readable):
+class DPM3(HasIodev, Drivable):
     OFFSET = 0x8f
     SCALE = 0x8c
     
@@ -52,8 +54,11 @@ class DPM3(HasIodev, Readable):
     
     iodevClass = DPM3IO
     
+    motor = Attached()
     digits = Parameter('number of digits for value', IntRange(0, 5), initwrite=True, readonly=False)
     value = Parameter(unit='N')
+    target = Parameter(unit='N')
+    step = Parameter('maximum motor step', FloatRange(unit='deg'), default=5, readonly=False)
 
     offset = Parameter('', FloatRange(-1e5, 1e5), readonly=False, poll=True)
     
@@ -62,6 +67,8 @@ class DPM3(HasIodev, Readable):
         thus a maximl output of 1500. 10=150/f 
     """
     scale_factor  = Parameter('', FloatRange(-1e5, 1e5, unit='input_units/N'), readonly=False, poll=True)
+    _target = None
+    fast_pollfactor = 0.01
     
     def query(self, adr, value=None):
         if value is not None:
@@ -93,7 +100,7 @@ class DPM3(HasIodev, Readable):
             return value/mag
         else:
             return hex2float(hexvalue, self.digits)
-    
+
     def write_digits(self, value):
         # value defines the number of digits
         back_value=self._iodev.communicate('*1F135%02X\r*1G135' % (value + 1))
@@ -108,9 +115,37 @@ class DPM3(HasIodev, Readable):
         return int(back_value,16) - 1
  
     def read_value(self):
-        value = self._iodev.communicate('*1B1')
-        return float(value)
+        value = float(self._iodev.communicate('*1B1'))
+        if self._target is not None:
+            mot = self._motor
+            if self._direction * (self._target - value) > 0:
+                if not mot.isBusy():
+                    step = self.step * self._direction
+                    mot.write_target(mot.value + step)
+            else:
+                print(value)
+                self.stop()
+                self.status = self.Status.IDLE, 'target reached'
+        return value
     
+    def write_target(self, target):
+        self._target = target
+        if target - self.value > 0:
+            self._direction = 1
+        else:
+            self._direction = -1
+        print('direction', self._direction)
+        self.status = self.Status.BUSY, 'moving motor'
+        if self._motor.status[0] == self.Status.ERROR:
+            self._motor.reset()
+        return target
+
+    @Command()
+    def stop(self):
+        self._target = None
+        self._motor.stop()
+        self.status = self.Status.IDLE, 'stopped'
+
     def read_offset(self):
         reply = self.query(self.OFFSET)
         return reply