Mercurial > pygpibtoolkit / changeset

--- a/pygpibtoolkit/HP3562A/HP356X.py	Mon Feb 25 18:38:27 2008 +0100
+++ b/pygpibtoolkit/HP3562A/HP356X.py	Mon Feb 25 19:50:49 2008 +0100
@@ -1,9 +1,9 @@
 #
-from  pygpibtoolkit.pygpib import CommandRegister, Constants, Command
-from  pygpibtoolkit.pygpib import BoolValue, IntValue, FloatValue
-from  pygpibtoolkit.pygpib import PercentageValue, FrequencyValue, DurationValue
-from  pygpibtoolkit.pygpib import EnumValue, StringValue
-from  pygpibtoolkit.pygpib import Mode, ModeCommand
+from pygpibtoolkit.pygpib import CommandRegister, Constants, Command
+from pygpibtoolkit.pygpib import BoolValue, IntValue, FloatValue
+from pygpibtoolkit.pygpib import PercentageValue, FrequencyValue, DurationValue
+from pygpibtoolkit.pygpib import EnumValue, StringValue
+from pygpibtoolkit.pygpib import Mode, ModeCommand
 
 from pygpibtoolkit.gpibcontroller import AbstractGPIBDevice, deviceRegister
 
@@ -233,25 +233,6 @@
 class HP356XDevice(AbstractGPIBDevice):
     _accepts = ["HP3562A", "HP3563A"]
     _idn = "ID?"
+    _cmd_register = Register
     
-    def __init__(self, idn, address, controller):
-        super(HP356XDevice, self).__init__(idn, address, controller)
-        self._registry = Register() # singleton
-        self._cache = dict([(k, None) for k, v in self._registry.items() if isinstance(v, Mode)])
-        for k in self._registry.keys():
-            setattr(self, 
-        
-    def _get(self, name):
-        print "get ", name
-        assert name in self._registry
-        if name in self._cache:
-            if self._cache[name] is None:
-                # where to get the info?
-                # ... compute value
-                self._cache[name] = value
-            return self._cache[name]
-        self._registry[name].get_value(self._cnx)
-    def _set(self, name, value):
-        assert name in self._registry
-        self._registry[name].set_value(self._cnx, value)
 deviceRegister.register_manager(HP356XDevice)

--- a/pygpibtoolkit/gpibcontroller.py	Mon Feb 25 18:38:27 2008 +0100
+++ b/pygpibtoolkit/gpibcontroller.py	Mon Feb 25 19:50:49 2008 +0100
@@ -5,10 +5,26 @@
 import sys
 import threading
 import time
+from inspect import isclass
+
+from serial.serialutil import SerialException
 from prologix import GPIB, GPIB_CONTROLLER, GPIB_DEVICE
+from pygpibtoolkit.pygpib import AbstractCommand
+
+class AbstractGPIBDeviceMetaclass(type):
+    def __new__(mcs, name, bases, classdict):
+        new_cls = type.__new__(mcs, name, bases, classdict)
+        module = sys.modules[new_cls.__module__]
+        for pname, param in module.__dict__.items():            
+            if isclass(param) and issubclass(param, AbstractCommand) and param.__module__ == new_cls.__module__:
+                setattr(new_cls, pname, param())
+        return new_cls
 
 class AbstractGPIBDevice(object):
+    __metaclass__ = AbstractGPIBDeviceMetaclass
     _accepts = []
+    _cmd_register = None # to be defined in son classes
+
     @classmethod
     def accepts(cls, idn):
         return idn in cls._accepts
@@ -18,6 +34,29 @@
         self._address = address
         self._controller = controller
 
+        self._registry = self._cmd_register() # singleton
+        self._cache = {}
+        for pname, param in self.__class__.__dict__.items():
+            if isinstance(param, AbstractCommand) and not param._readonly:
+                self._cache[pname] = param._init_value
+        
+    def _get(self, name):
+        assert name in self._registry
+        if name in self._cache:
+            if self._cache[name] is None:
+                # where to get the info?
+                # ... compute value
+                value = self._registry[name].get_value(self._cnx)
+                self._cache[name] = value
+            return self._cache[name]
+
+    def _set(self, name, value):
+        assert name in self._registry
+        res = self._registry[name].set_value(self._cnx, value)
+        if name in self._cache:
+            self._cache[name] = value
+        return res
+    
     def manage_srq(self):
         pass
 
@@ -69,7 +108,10 @@
     """
     def __init__(self, device="/dev/ttyUSB0", controller_address=21):
         self._address = controller_address
-        self._cnx = GPIB(device)
+        try:
+            self._cnx = GPIB(device)
+        except SerialException:
+            self._cnx = None
         self._devices = {}
         self._setup_threading_system()
 
@@ -92,7 +134,7 @@
         self._loop_interrupter.set()
         
     def _check_srq(self):
-        if self._cnx.check_srq():
+        if self._cnx and self._cnx.check_srq():
             addrs = sorted(self._devices.keys())
             polled = self._cnx.poll(addrs)
             for add in addrs:

--- a/pygpibtoolkit/pygpib.py	Mon Feb 25 18:38:27 2008 +0100
+++ b/pygpibtoolkit/pygpib.py	Mon Feb 25 19:50:49 2008 +0100
@@ -95,9 +95,24 @@
             CommandRegister().add(cls)
     
 class AbstractCommand(object):
-    """ Base class for HPIB command descritption"""
+    """
+    Base class for HPIB command descritption.
+
+    This is actually a attribute descriptor, which should have
+    AbstractGPIBDevice derived classes as owner.
+    """
     __metaclass__ = MetaCommand
+    _readonly = True
+    _init_value = None
     
+    def __get__(self, instance, owner):
+        if instance is None:
+            return self
+        return instance._get(self.__class__.__name__)
+    def __set__(self, instance, value):
+        if instance is None:
+            return self
+        return instance._set(self.__class__.__name__, value)
 
 class Command(AbstractCommand):
     @classmethod
@@ -114,10 +129,11 @@
         return value
     
 class AbstractValue(Command):
+    _readonly = False
     @classmethod
     def set_value(self, cnx, value):
-        res = cnx.send_command("%s %s"%(self.__class__.__name__,
-                                        self.convert_to(value)))
+        value = self.convert_to(value)
+        res = cnx.send_command("%s %s"%(self.__class__.__name__, value)
         return res
     @classmethod
     def convert_to(self, value):